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Drug overview for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan):
Generic name: diphenhydramine/brompheniramine/phenyleph/dextromethorphan
Drug class: Amphetamines/Anorexiants/Stimulants
Therapeutic class: Respiratory Therapy Agents
Brompheniramine and dexbrompheniramine are alkylamine Dextromethorphan, a derivative of levorphanol, is an antitussive agent. Diphenhydramine is an ethanolamine-derivative, first generation Phenylephrine hydrochloride is an alpha1-adrenergic receptor agonist. (propylamine)-derivative first generation antihistamines. antihistamine.
Brompheniramine and dexbrompheniramine share the actions and uses of other Dextromethorphan is used for the temporary relief of coughs caused by minor Diphenhydramine shares the actions and uses of other antihistamines. antihistamines. Preparations containing brompheniramine maleate or throat and bronchial irritation such as may occur with common colds or with dexbrompheniramine maleate in fixed combination with other agents (e.g., Diphenhydramine also is used as an antitussive for temporary relief of inhaled irritants. Dextromethorphan is most effective in the treatment of chronic, nonproductive cough. The drug is a common ingredient in commercial cough caused by minor throat and bronchial irritation such as may occur dextromethorphan, guaifenesin, phenylephrine, pseudoephedrine) are used for cough mixtures available without prescription.
relief of rhinorrhea, sneezing, lacrimation, itching eyes, with common colds or inhaled irritants. oronasopharyngeal itching, and/or other symptoms (e.g., nasal/sinus Although cough and cold preparations that contain cough suppressants congestion, cough) associated with allergic rhinitis (e.g., hay fever), Diphenhydramine is effective for the prevention and treatment of nausea, (including dextromethorphan), nasal decongestants, antihistamines, and/or other upper respiratory allergies, or the common cold. Combination vomiting, and/or vertigo associated with motion sickness.
expectorants commonly are used in pediatric patients younger than 2 years preparations generally should only be used when symptoms amenable to each Diphenhydramine may be useful as an adjunctive antiemetic agent to prevent ingredient are present concurrently. of age, systematic reviews of controlled trials have concluded that chemotherapy-induced nausea and vomiting+; however, the American Society of nonprescription (over-the-counter, OTC) cough and cold preparations are not Clinical Oncology (ASCO) currently does not recommend that antihistamines more effective than placebo in reducing acute cough and other symptoms of be used alone as antiemetic agents in patients receiving chemotherapy. upper respiratory tract infection in these patients.
Furthermore, adverse events, including deaths, have been (and continue to be) reported in Diphenhydramine also is used as a nighttime sleep aid for the short-term pediatric patients younger than 2 years of age receiving these management of insomnia. In individuals who experience occasional preparations. (See Cautions: Pediatric Precautions and see Acute Toxicity: Manifestations.) sleeplessness or those who have difficulty falling asleep, the drug is more effective than placebo in reducing sleep onset (i.e., time to fall asleep) and increasing the depth and quality of sleep.
For information on abuse of dextromethorphan, see Cautions. Diphenhydramine, alone or in conjunction with other antiparkinsonian For use of dextromethorphan hydrobromide in fixed combination with agents, may be useful as alternative therapy in the management of tremor quinidine sulfate in the treatment of pseudobulbar affect (PBA), see Dextromethorphan Hydrobromide and Quinidine Sulfate 28:92. early in the course of parkinsonian syndrome.
The drug also may be useful in the management of drug-induced extrapyramidal reactions. Diphenhydramine may be used topically for temporary relief of pruritus and pain associated with various skin conditions including minor burns, sunburn, minor cuts or scrapes, insect bites, minor skin irritations, or rashes associated with poison oak, poison ivy, or poison sumac. However, because systemic diphenhydramine toxicity (e.g., psychosis) has been reported in pediatric patients following topical application of the drug to large areas of the body (often areas with broken skin), many clinicians suggest that topical diphenhydramine be used only on limited areas of skin and not used more often than directed to avoid excessive percutaneous absorption of the drug.
(See Acute Toxicity: Manifestations, in the Antihistamines General Statement 4:00.) Topical diphenhydramine also should not be used for self-medication in the management of varicella (chickenpox) or measles without first consulting a clinician.
Generic name: diphenhydramine/brompheniramine/phenyleph/dextromethorphan
Drug class: Amphetamines/Anorexiants/Stimulants
Therapeutic class: Respiratory Therapy Agents
Brompheniramine and dexbrompheniramine are alkylamine Dextromethorphan, a derivative of levorphanol, is an antitussive agent. Diphenhydramine is an ethanolamine-derivative, first generation Phenylephrine hydrochloride is an alpha1-adrenergic receptor agonist. (propylamine)-derivative first generation antihistamines. antihistamine.
Brompheniramine and dexbrompheniramine share the actions and uses of other Dextromethorphan is used for the temporary relief of coughs caused by minor Diphenhydramine shares the actions and uses of other antihistamines. antihistamines. Preparations containing brompheniramine maleate or throat and bronchial irritation such as may occur with common colds or with dexbrompheniramine maleate in fixed combination with other agents (e.g., Diphenhydramine also is used as an antitussive for temporary relief of inhaled irritants. Dextromethorphan is most effective in the treatment of chronic, nonproductive cough. The drug is a common ingredient in commercial cough caused by minor throat and bronchial irritation such as may occur dextromethorphan, guaifenesin, phenylephrine, pseudoephedrine) are used for cough mixtures available without prescription.
relief of rhinorrhea, sneezing, lacrimation, itching eyes, with common colds or inhaled irritants. oronasopharyngeal itching, and/or other symptoms (e.g., nasal/sinus Although cough and cold preparations that contain cough suppressants congestion, cough) associated with allergic rhinitis (e.g., hay fever), Diphenhydramine is effective for the prevention and treatment of nausea, (including dextromethorphan), nasal decongestants, antihistamines, and/or other upper respiratory allergies, or the common cold. Combination vomiting, and/or vertigo associated with motion sickness.
expectorants commonly are used in pediatric patients younger than 2 years preparations generally should only be used when symptoms amenable to each Diphenhydramine may be useful as an adjunctive antiemetic agent to prevent ingredient are present concurrently. of age, systematic reviews of controlled trials have concluded that chemotherapy-induced nausea and vomiting+; however, the American Society of nonprescription (over-the-counter, OTC) cough and cold preparations are not Clinical Oncology (ASCO) currently does not recommend that antihistamines more effective than placebo in reducing acute cough and other symptoms of be used alone as antiemetic agents in patients receiving chemotherapy. upper respiratory tract infection in these patients.
Furthermore, adverse events, including deaths, have been (and continue to be) reported in Diphenhydramine also is used as a nighttime sleep aid for the short-term pediatric patients younger than 2 years of age receiving these management of insomnia. In individuals who experience occasional preparations. (See Cautions: Pediatric Precautions and see Acute Toxicity: Manifestations.) sleeplessness or those who have difficulty falling asleep, the drug is more effective than placebo in reducing sleep onset (i.e., time to fall asleep) and increasing the depth and quality of sleep.
For information on abuse of dextromethorphan, see Cautions. Diphenhydramine, alone or in conjunction with other antiparkinsonian For use of dextromethorphan hydrobromide in fixed combination with agents, may be useful as alternative therapy in the management of tremor quinidine sulfate in the treatment of pseudobulbar affect (PBA), see Dextromethorphan Hydrobromide and Quinidine Sulfate 28:92. early in the course of parkinsonian syndrome.
The drug also may be useful in the management of drug-induced extrapyramidal reactions. Diphenhydramine may be used topically for temporary relief of pruritus and pain associated with various skin conditions including minor burns, sunburn, minor cuts or scrapes, insect bites, minor skin irritations, or rashes associated with poison oak, poison ivy, or poison sumac. However, because systemic diphenhydramine toxicity (e.g., psychosis) has been reported in pediatric patients following topical application of the drug to large areas of the body (often areas with broken skin), many clinicians suggest that topical diphenhydramine be used only on limited areas of skin and not used more often than directed to avoid excessive percutaneous absorption of the drug.
(See Acute Toxicity: Manifestations, in the Antihistamines General Statement 4:00.) Topical diphenhydramine also should not be used for self-medication in the management of varicella (chickenpox) or measles without first consulting a clinician.
DRUG IMAGES
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The following indications for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan) have been approved by the FDA:
Indications:
Allergic rhinitis
Cold symptoms
Cough
Nasal congestion
Rhinorrhea
Vasomotor rhinitis
Professional Synonyms:
Nasal stuffiness
Indications:
Allergic rhinitis
Cold symptoms
Cough
Nasal congestion
Rhinorrhea
Vasomotor rhinitis
Professional Synonyms:
Nasal stuffiness
The following dosing information is available for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan):
Dosage of brompheniramine maleate and dexbrompheniramine maleate is Dosage should be individualized according to the patient's response and Dosages of dextromethorphan hydrobromide and dextromethorphan polistirex are expressed in terms of dextromethorphan hydrobromide. expressed in terms of the salt. Dosage of brompheniramine maleate and tolerance.
dexbrompheniramine maleate should be individualized according to the patient's response and tolerance. The usual dosage of dextromethorphan hydrobromide for adults and children
12 years of age or older is 10-20 mg every 4 hours or 30 mg every 6-8 Fixed-ratio combination preparations do not permit individual titration of hours, not to exceed 120 mg daily, or as directed by a clinician. The usual dosage for children 6 to younger than 12 years of age is 5-10 mg every 4 dosages; if a fixed combination is used, the precautions and contraindications associated with each drug must be considered. hours or 15 mg every 6-8 hours, not to exceed 60 mg daily, or as directed
by a clinician. Children 2 to younger than 6 years of age may receive 2.5-5 mg every 4 hours or 7.5
mg every 6-8 hours, not to exceed 30 mg daily, or as directed by a clinician. Dosage in children younger than 2 years of age must be individualized. Suggested dosages for children younger than 2 years of age+ for some cough and cold preparations have been published in various references for prescribing and parenting.
Using recommended dosages for adults and older children, some clinicians have extrapolated dosages for these preparations based on the weight or age of children younger than 2 years of age. However, these extrapolations were based on assumptions that pathology of the disease and pharmacology of the drugs are similar in adults and pediatric patients. There currently are no specific dosage recommendations (i.e., approved by the US Food and Drug Administration (FDA)) for cough and cold preparations for this patient population.
(See Cautions: Pediatric Precautions.)
The usual dosage of dextromethorphan hydrobromide as the extended-release oral suspension containing the polistirex for adults and children 12 years of age or older is 60 mg twice daily. The usual dosage as the extended-release oral suspension for children 6 to younger than 12 years of age is 30 mg twice daily; children 2 to younger than 6 years of age may receive 15 mg twice daily.
The usual adult oral dosage of diphenhydramine hydrochloride is 25-50 mg 3 or 4 times daily at 4- to 6-hour intervals, not to exceed 300 mg in 24 hours.
The usual adult IM or IV dose of diphenhydramine hydrochloride is 10-50 mg; in a few patients, up to 100 mg may be required. Some experts recommend a dose of 25-50 mg. The rate of IV administration should not exceed 25 mg/minute.
The maximum adult IM or IV dosage of diphenhydramine hydrochloride is 400 mg daily.
When diphenhydramine was available only by prescription, the prescribing information for the drug indicated a usual oral diphenhydramine hydrochloride dosage for children weighing more than 9.1 kg of 12.5-25 mg 3 or 4 times daily at 4- to 6-hour intervals and for children weighing 9.1
kg or less an oral diphenhydramine hydrochloride dosage of 6.25-12.5 mg 3 or 4 times daily at 4- to 6-hour intervals.
However, these dosage recommendations are not included in the current labeling of nonprescription oral diphenhydramine preparations, and clinicians should use caution when considering use of nonprescription oral diphenhydramine in children younger than 4 years of age. (See Cautions: Pediatric Precautions.)
Alternatively, for oral, deep IM, or IV therapy, children (other than premature or full-term neonates) may be given 5 mg/kg daily or 150 mg/m2 daily divided in 4 doses; some experts recommend a dosage of 1-2 mg/kg daily. The rate of IV administration should not exceed 25 mg/minute.
The maximum oral, IM, or IV dosage of diphenhydramine hydrochloride in children older than 1 month of age is 300 mg daily.
For temporary relief of pruritus and pain associated with various skin conditions in adults and children 2 years of age or older, creams, lotions, or solutions containing 1-2% diphenhydramine hydrochloride are applied to the affected areas 3 or 4 times daily or as directed by a clinician; topical diphenhydramine should not be used more often than directed.
If the condition worsens, or if symptoms persist for longer than 7 days or resolve and then recur within a few days, topical therapy with diphenhydramine hydrochloride should be discontinued and a clinician consulted; the possibility of sensitization by, or hypersensitivity to, the drug should be considered.
Topical preparations containing diphenhydramine hydrochloride should not be used on large areas of the body or concomitantly with other preparations containing the antihistamine, including those used orally, since increased serum concentrations of diphenhydramine may occur that can result in systemic toxicity. (See Acute Toxicity: Manifestations, in the Antihistamines General Statement 4:00.) The drug also should not be used for topical self-medication in the management of varicella (chickenpox) or measles without first consulting a clinician.
dexbrompheniramine maleate should be individualized according to the patient's response and tolerance. The usual dosage of dextromethorphan hydrobromide for adults and children
12 years of age or older is 10-20 mg every 4 hours or 30 mg every 6-8 Fixed-ratio combination preparations do not permit individual titration of hours, not to exceed 120 mg daily, or as directed by a clinician. The usual dosage for children 6 to younger than 12 years of age is 5-10 mg every 4 dosages; if a fixed combination is used, the precautions and contraindications associated with each drug must be considered. hours or 15 mg every 6-8 hours, not to exceed 60 mg daily, or as directed
by a clinician. Children 2 to younger than 6 years of age may receive 2.5-5 mg every 4 hours or 7.5
mg every 6-8 hours, not to exceed 30 mg daily, or as directed by a clinician. Dosage in children younger than 2 years of age must be individualized. Suggested dosages for children younger than 2 years of age+ for some cough and cold preparations have been published in various references for prescribing and parenting.
Using recommended dosages for adults and older children, some clinicians have extrapolated dosages for these preparations based on the weight or age of children younger than 2 years of age. However, these extrapolations were based on assumptions that pathology of the disease and pharmacology of the drugs are similar in adults and pediatric patients. There currently are no specific dosage recommendations (i.e., approved by the US Food and Drug Administration (FDA)) for cough and cold preparations for this patient population.
(See Cautions: Pediatric Precautions.)
The usual dosage of dextromethorphan hydrobromide as the extended-release oral suspension containing the polistirex for adults and children 12 years of age or older is 60 mg twice daily. The usual dosage as the extended-release oral suspension for children 6 to younger than 12 years of age is 30 mg twice daily; children 2 to younger than 6 years of age may receive 15 mg twice daily.
The usual adult oral dosage of diphenhydramine hydrochloride is 25-50 mg 3 or 4 times daily at 4- to 6-hour intervals, not to exceed 300 mg in 24 hours.
The usual adult IM or IV dose of diphenhydramine hydrochloride is 10-50 mg; in a few patients, up to 100 mg may be required. Some experts recommend a dose of 25-50 mg. The rate of IV administration should not exceed 25 mg/minute.
The maximum adult IM or IV dosage of diphenhydramine hydrochloride is 400 mg daily.
When diphenhydramine was available only by prescription, the prescribing information for the drug indicated a usual oral diphenhydramine hydrochloride dosage for children weighing more than 9.1 kg of 12.5-25 mg 3 or 4 times daily at 4- to 6-hour intervals and for children weighing 9.1
kg or less an oral diphenhydramine hydrochloride dosage of 6.25-12.5 mg 3 or 4 times daily at 4- to 6-hour intervals.
However, these dosage recommendations are not included in the current labeling of nonprescription oral diphenhydramine preparations, and clinicians should use caution when considering use of nonprescription oral diphenhydramine in children younger than 4 years of age. (See Cautions: Pediatric Precautions.)
Alternatively, for oral, deep IM, or IV therapy, children (other than premature or full-term neonates) may be given 5 mg/kg daily or 150 mg/m2 daily divided in 4 doses; some experts recommend a dosage of 1-2 mg/kg daily. The rate of IV administration should not exceed 25 mg/minute.
The maximum oral, IM, or IV dosage of diphenhydramine hydrochloride in children older than 1 month of age is 300 mg daily.
For temporary relief of pruritus and pain associated with various skin conditions in adults and children 2 years of age or older, creams, lotions, or solutions containing 1-2% diphenhydramine hydrochloride are applied to the affected areas 3 or 4 times daily or as directed by a clinician; topical diphenhydramine should not be used more often than directed.
If the condition worsens, or if symptoms persist for longer than 7 days or resolve and then recur within a few days, topical therapy with diphenhydramine hydrochloride should be discontinued and a clinician consulted; the possibility of sensitization by, or hypersensitivity to, the drug should be considered.
Topical preparations containing diphenhydramine hydrochloride should not be used on large areas of the body or concomitantly with other preparations containing the antihistamine, including those used orally, since increased serum concentrations of diphenhydramine may occur that can result in systemic toxicity. (See Acute Toxicity: Manifestations, in the Antihistamines General Statement 4:00.) The drug also should not be used for topical self-medication in the management of varicella (chickenpox) or measles without first consulting a clinician.
Brompheniramine maleate and dexbrompheniramine maleate are administered Dextromethorphan preparations are administered orally. Lozenges containing Diphenhydramine hydrochloride usually is administered orally. dextromethorphan hydrobromide should not be used in children younger than 6 orally.
These agents should be administered with food, water, or milk to Diphenhydramine citrate usually is administered orally. minimize gastric irritation. years of age and liquid-filled capsules containing the drug should not be used in children younger than 12 years of age, unless otherwise directed by a clinician.
Doses of brompheniramine maleate oral solution should be measured using the When oral therapy is not feasible, diphenhydramine hydrochloride may be given by deep IM or, preferably, IV injection. The drug should not be given measuring device (e.g., calibrated dropper, cup, spoon) provided by the manufacturer. subcutaneously, intradermally, or perivascularly because of its irritating effects; local necrosis has been reported following subcutaneous or intradermal administration of parenteral diphenhydramine.
IV use of the drug in a home-care setting should be employed under careful supervision. Use of diphenhydramine for local anesthesia via local infiltration is discouraged because of the risk of local tissue necrosis. Diphenhydramine hydrochloride should not be given to premature or full-term neonates.
(See Cautions: Pediatric Precautions.) For the temporary relief of pruritus associated with various skin conditions and disorders, diphenhydramine hydrochloride-containing preparations are applied topically in the form of a cream, lotion, or topical solution. The possibility of clinically important percutaneous absorption of the drug following topical application should be considered. (See Cautions.) Phenylephrine hydrochloride is administered by IV bolus or continuous IV infusion for the treatment of clinically important hypotension.
The drug is available as a 10 mg/mL phenylephrine hydrochloride injection concentrate that must be diluted prior to administration and as a ready-to-use phenylephrine hydrochloride 100 mcg/mL (Immphentiv(R), Biorphen(R)) injection. Ready-to-use phenylephrine hydrochloride 100 mcg/mL (Immphentiv(R), Biorphen(R)) injection should not be further diluted before IV bolus administration. For treatment of hypotension during anesthesia, the manufacturers recommend administration of phenylephrine hydrochloride as an IV bolus or continuous infusion; when used in the treatment of septic shock, the drug should be administered as a continuous IV infusion with no initial bolus dose.
Phenylephrine hydrochloride injection should be stored at 20-25degreesC, but may be exposed to temperatures ranging from 15-30degreesC; single-dose and pharmacy bulk vials should be kept in their original carton until time of use and protected from light. Commercially available phenylephrine hydrochloride injection concentrate must be diluted with a compatible IV solution prior to administration. Diluted solutions may be stored at room temperature for up to 4 hours or under refrigeration for up to 24 hours; any unused portions should be discarded.
Commercially available phenylephrine hydrochloride bulk vials are intended for use in a pharmacy admixture program for preparation of single doses to be dispensed to multiple patients. Each vial should be penetrated only one time with a suitable sterile transfer device or dispensing set. Dispensing from a pharmacy bulk vial should be completed within 4 hours after the vial is penetrated.
Prior to administration, phenylephrine hydrochloride solutions should be inspected visually for particulate matter and discoloration; the drug should be discarded if the solution is colored, cloudy, or contains any particulate matter. Care should be taken to avoid extravasation and the infusion site should be checked for free flow.
These agents should be administered with food, water, or milk to Diphenhydramine citrate usually is administered orally. minimize gastric irritation. years of age and liquid-filled capsules containing the drug should not be used in children younger than 12 years of age, unless otherwise directed by a clinician.
Doses of brompheniramine maleate oral solution should be measured using the When oral therapy is not feasible, diphenhydramine hydrochloride may be given by deep IM or, preferably, IV injection. The drug should not be given measuring device (e.g., calibrated dropper, cup, spoon) provided by the manufacturer. subcutaneously, intradermally, or perivascularly because of its irritating effects; local necrosis has been reported following subcutaneous or intradermal administration of parenteral diphenhydramine.
IV use of the drug in a home-care setting should be employed under careful supervision. Use of diphenhydramine for local anesthesia via local infiltration is discouraged because of the risk of local tissue necrosis. Diphenhydramine hydrochloride should not be given to premature or full-term neonates.
(See Cautions: Pediatric Precautions.) For the temporary relief of pruritus associated with various skin conditions and disorders, diphenhydramine hydrochloride-containing preparations are applied topically in the form of a cream, lotion, or topical solution. The possibility of clinically important percutaneous absorption of the drug following topical application should be considered. (See Cautions.) Phenylephrine hydrochloride is administered by IV bolus or continuous IV infusion for the treatment of clinically important hypotension.
The drug is available as a 10 mg/mL phenylephrine hydrochloride injection concentrate that must be diluted prior to administration and as a ready-to-use phenylephrine hydrochloride 100 mcg/mL (Immphentiv(R), Biorphen(R)) injection. Ready-to-use phenylephrine hydrochloride 100 mcg/mL (Immphentiv(R), Biorphen(R)) injection should not be further diluted before IV bolus administration. For treatment of hypotension during anesthesia, the manufacturers recommend administration of phenylephrine hydrochloride as an IV bolus or continuous infusion; when used in the treatment of septic shock, the drug should be administered as a continuous IV infusion with no initial bolus dose.
Phenylephrine hydrochloride injection should be stored at 20-25degreesC, but may be exposed to temperatures ranging from 15-30degreesC; single-dose and pharmacy bulk vials should be kept in their original carton until time of use and protected from light. Commercially available phenylephrine hydrochloride injection concentrate must be diluted with a compatible IV solution prior to administration. Diluted solutions may be stored at room temperature for up to 4 hours or under refrigeration for up to 24 hours; any unused portions should be discarded.
Commercially available phenylephrine hydrochloride bulk vials are intended for use in a pharmacy admixture program for preparation of single doses to be dispensed to multiple patients. Each vial should be penetrated only one time with a suitable sterile transfer device or dispensing set. Dispensing from a pharmacy bulk vial should be completed within 4 hours after the vial is penetrated.
Prior to administration, phenylephrine hydrochloride solutions should be inspected visually for particulate matter and discoloration; the drug should be discarded if the solution is colored, cloudy, or contains any particulate matter. Care should be taken to avoid extravasation and the infusion site should be checked for free flow.
No dosing information available.
No generic dosing information available.
The following drug interaction information is available for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan):
There are 5 contraindications.
These drug combinations generally should not be dispensed or administered to the same patient. A manufacturer label warning that indicates the contraindication warrants inclusion of a drug combination in this category, regardless of clinical evidence or lack of clinical evidence to support the contraindication.
| Drug Interaction | Drug Names |
|---|---|
| Mixed & Indirect Sympathomimetics; Oral Phenylephrine/MAOIs SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient. MECHANISM OF ACTION: Catecholamine stores increased by MAOIs can be released by indirect acting sympathomimetics such as ephedrine and amphetamine. MAO inhibitors also interfere with gut and liver metabolism of direct acting sympathomimetics (e.g oral phenylephrine). CLINICAL EFFECTS: Concurrent use of MAOIs may result in potentiation of sympathomimetic effects, which may result in headaches, hypertensive crisis, toxic neurological effects, and malignant hyperpyrexia. Fatalities have occurred. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Concurrent use of monoamine oxidase inhibitors and sympathomimetics is contraindicated. The manufacturers of sympathomimetic agents recommend waiting 14 days after discontinuation of MAO inhibitors before initiating the sympathomimetic. DISCUSSION: Indirect acting sympathomimetic amines may cause abrupt elevation of blood pressure when administered to patients taking monoamine oxidase inhibitors, resulting in a potentially fatal hypertensive crisis. Mixed (direct and indirect) acting sympathomimetics have also been shown to interact with monoamine oxidase inhibitors depending on their degree of indirect action. The direct-acting sympathomimetics have not been reported to interact. Dopamine is metabolized by monoamine oxidase, and its pressor effect is enhanced by monoamine oxidase inhibitors. Since procarbazine, an antineoplastic agent, is a weak monoamine oxidase inhibitor, hypertensive reactions may result from its concurrent use with indirect and mixed acting sympathomimetics. Furazolidone, an antibacterial with monoamine oxidase inhibitor action, has also been shown to interact with indirect acting sympathomimetics. Linezolid is another antibacterial with monoamine oxidase inhibitor properties. Metaxalone is a weak inhibitor of MAO. Foods containing large amounts of tyramine have also been implicated in this interaction. Methylene blue, when administered intravenously, has been shown to reach sufficient concentrations to be a potent inhibitor of MAO-A. At recommended dosages, rasagiline, oral selegiline, and transdermal selegiline up to 6mg/day are selective for MAO-B; however, at higher dosages they have been shown to lose their selectivity. One or more of the drug pairs linked to this monograph have been included in a list of interactions that should be considered "high-priority" for inclusion and should not be inactivated in EHR systems. This DDI subset was vetted by an expert panel commissioned by the U.S. Office of the National Coordinator (ONC) for Health Information Technology. |
EMSAM, FURAZOLIDONE, MARPLAN, MATULANE, METAXALONE, METHYLENE BLUE, NARDIL, PARNATE, PHENELZINE SULFATE, PROCARBAZINE HCL, PROVAYBLUE, SELEGILINE HCL, TRANYLCYPROMINE SULFATE |
| Selected Opioids; Dextromethorphan/Selected MAOIs SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient. MECHANISM OF ACTION: Selected opioids inhibit neural reuptake of serotonin. MAOIs may increase neuronal serotonin concentrations via inhibition of MAO-A.(26) CLINICAL EFFECTS: The concurrent use of selected opioids with MAOIs has resulted in hypotension, hyperpyrexia, sedation, somnolence, and death. Symptoms of serotonin syndrome may include tremor, agitation, diaphoresis, hyperreflexia, clonus, tachycardia, hyperthermia, and muscle rigidity.(26) PREDISPOSING FACTORS: Higher opioid concentrations as may occur due to inhibition of opioid clearance, patient specific genomic factors (e.g. poor metabolizer status for a P450 enzyme), or high opioid dosage may increase the risk for a severe interaction. PATIENT MANAGEMENT: Dextromethorphan, diamorphine, meperidine, and tapentadol should not be used in patients taking MAOIs. Use alternative agents for cough or pain. The US manufacturer of Nuedexta(dextromethorphan-quinidine) states Nuedexta is contraindicated within 14 days of MAOI administration.(28) Quinidine increases systemic dextromethorphan concentrations 10 to 20-fold. Other strong CYP2D6 inhibitors such as bupropion, fluoxetine and paroxetine could similarly increase dextromethorphan levels. The US manufacturer of selegiline states that concurrent use with dextromethorphan or meperidine is contraindicated. The US manufacturers of meperidine and tapentadol and the UK manufacturer of diamorphine state that they should not be used concurrently with or within 14 days of taking an MAOI. DISCUSSION: The interaction between meperidine and MAOIs has been well documented. There are at least two reports of potential interactions between MAOIs and dextromethorphan. Concomitant use of quinidine, a strong CYP2D6 inhibitor, increases systemic dextromethorphan concentrations 10 to 20-fold. Other strong CYP2D6 inhibitors such as bupropion, fluoxetine and paroxetine could similarly increase dextromethorphan levels and risk for serotonin toxicity in patients also receiving MAOIs. Furazolidone is known to be a monoamine oxidase inhibitor. Methylene blue, when administered intravenously, has been shown to reach sufficient concentrations to be a potent inhibitor of MAO-A. One or more of the drug pairs linked to this monograph have been included in a list of interactions that should be considered "high-priority" for inclusion and should not be inactivated in EHR systems. This DDI subset was vetted by an expert panel commissioned by the U.S. Office of the National Coordinator (ONC) for Health Information Technology. |
AZILECT, EMSAM, FURAZOLIDONE, MARPLAN, MATULANE, METHYLENE BLUE, NARDIL, PARNATE, PHENELZINE SULFATE, PROCARBAZINE HCL, PROVAYBLUE, RASAGILINE MESYLATE, SELEGILINE HCL, TRANYLCYPROMINE SULFATE, XADAGO, ZELAPAR |
| Dextromethorphan/Metaxalone SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient. MECHANISM OF ACTION: Dextromethorphan inhibits neural reuptake of serotonin. Metaxalone, a weak inhibitor of MAO, may increase neuronal serotonin concentrations.(1) CLINICAL EFFECTS: The concurrent use of dextromethorphan with MAOIs may result in hypotension, hyperpyrexia, sedation, somnolence, and death. Symptoms of serotonin syndrome may include tremor, agitation, diaphoresis, hyperreflexia, clonus, tachycardia, hyperthermia, and muscle rigidity.(1) PREDISPOSING FACTORS: Higher opioid concentrations as may occur due to inhibition of opioid clearance, patient specific genomic factors (e.g. poor metabolizer status for a P450 enzyme), or high opioid dosage may increase the risk for a severe interaction. PATIENT MANAGEMENT: Dextromethorphan should not be used in patients taking MAOIs such as metaxalone. Use alternative agents for cough. The US manufacturer of Nuedexta (dextromethorphan-quinidine) states Nuedexta is contraindicated within 14 days of MAOI administration.(1) Quinidine increases systemic dextromethorphan concentrations 10 to 20-fold. DISCUSSION: Metaxalone is a weak inhibitor of MAO.(2,3) There are at least two reports of potential interactions between MAOIs and dextromethorphan. Concomitant use of quinidine, a strong CYP2D6 inhibitor, increases systemic dextromethorphan concentrations 10 to 20-fold. Other strong CYP2D6 inhibitors such as bupropion, fluoxetine and paroxetine could similarly increase dextromethorphan levels and risk for serotonin toxicity in patients also receiving MAOIs.(4,5) |
METAXALONE |
| Selected CYP2D6 Substrates/Mavorixafor SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient. MECHANISM OF ACTION: Mavorixafor is a strong inhibitor of CYP2D6 and is expected to inhibit the metabolism of agents through this pathway.(1) CLINICAL EFFECTS: Concurrent use of mavorixafor may result in elevated levels of and toxicity from agents metabolized by CYP2D6.(1) PREDISPOSING FACTORS: With tricyclic antidepressants, the risk of seizures may be increased in patients with a history of head trauma or prior seizure; CNS tumor; severe hepatic cirrhosis; excessive use of alcohol or sedatives; addiction to opiates, cocaine, or stimulants; use of over-the-counter stimulants and anorectics; diabetics treated with oral hypoglycemics or insulin; or with concomitant medications known to lower seizure threshold (antipsychotics, theophylline, systemic steroids). With anticholinergic agents, the risk of anticholinergic toxicities including cognitive decline, delirium, falls and fractures is increased in geriatric patients using more than one medicine with anticholinergic properties.(2) PATIENT MANAGEMENT: The US manufacturer of mavorixafor states concurrent use with CYP2D6 substrate that are highly dependent on CYP2D6 metabolism is contraindicated.(1) The US manufacturer of doxepin states if concurrent use of doxepin and strong CYP2D6 inhibitors such as mavorixafor is warranted, monitor doxepin plasma concentrations and reduce the doxepin dose based on doxepin plasma concentrations.(5) DISCUSSION: Mavorixafor (400 mg) increased dextromethorphan (CYP2D6 substrate) maximum concentration (Cmax) and area-under-curve (AUC) by 6-fold and 9-fold, respectively.(1) Selected CYP2D6 substrates linked to this monograph include: aripiprazole, brexpiprazole, desipramine, deutetrabenazine, dextromethorphan, doxepin, encainide, fenfluramine, metoclopramide, methoxyphenamine, metoprolol, mexiletine, nebivolol, paroxetine, perphenazine, risperidone, tetrabenazine, trimipramine, venlafaxine, and yohimbine. |
XOLREMDI |
| Dihydroergotamine/Sympathomimetics SEVERITY LEVEL: 1-Contraindicated Drug Combination: This drug combination is contraindicated and generally should not be dispensed or administered to the same patient. MECHANISM OF ACTION: Concurrent use of dihydroergotamine and sympathomimetics may result in additive or synergistic effect on peripheral blood vessels.(1) CLINICAL EFFECTS: Concurrent use of dihydroergotamine and sympathomimetics may result in increased blood pressure due to peripheral vasoconstriction.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Dihydroergotamine is contraindicated with sympathomimetics because the combination may result in additive or synergistic elevation of blood pressure.(1) DISCUSSION: Significant elevation in blood pressure has been reported in patients treated with dihydroergotamine.(1) Sympathomimetics can be expected to have additional effects on blood pressure. |
BREKIYA, DIHYDROERGOTAMINE MESYLATE, MIGRANAL, TRUDHESA |
There are 15 severe interactions.
These drug interactions can produce serious consequences in most patients. Actions required for severe interactions include, but are not limited to, discontinuing one or both agents, adjusting dosage, altering administration scheduling, and providing additional patient monitoring. Review the full interaction monograph for more information.
| Drug Interaction | Drug Names |
|---|---|
| Ergot Alkaloids/Sympathomimetics SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Concurrent use of ergot alkaloids and sympathomimetics may result in additive or synergistic effect on peripheral blood vessels. CLINICAL EFFECTS: Concurrent use of ergot alkaloids and sympathomimetics may result in increased blood pressure due to peripheral vasoconstriction. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: When possible, avoid the concurrent use of ergot alkaloids and sympathomimetics. If concurrent use is warranted, monitor blood pressure and for signs of vasoconstriction. Decreasing the dose of one or both drugs may be necessary. DISCUSSION: There have been reports of severe vasoconstriction resulting in gangrene in patients receiving intravenous ergonovine with dopamine or norepinephrine. |
ERGOLOID MESYLATES, ERGOMAR, ERGOTAMINE TARTRATE, ERGOTAMINE-CAFFEINE, METHYLERGONOVINE MALEATE, METHYSERGIDE MALEATE, MIGERGOT |
| Selected Inhalation Anesthetic Agents/Sympathomimetics SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The exact mechanism is unknown. The anesthetics produce conduction changes that increase impulse re-entry into the myocardial tissue.(1) The anesthetics' ability to precipitate arrhythmias is enhanced by elevated arterial blood pressure, tachycardia, hypercapnia, and/or hypoxia, events that stimulate the release of endogenous catecholamines.(1) CLINICAL EFFECTS: Concurrent use of inhalation anesthetic agents and sympathomimetics may result in ventricular arrhythmias or sudden blood pressure and heart rate increase during surgery.(2) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Monitor blood pressure and avoid use of sympathomimetics in patients being treated with anesthetics on the day of surgery.(2) Intravenous use of epinephrine during surgery with halothane and related halogenated general anesthetics should be strongly discouraged. When intravenous epinephrine is necessary, nitrous oxide anesthesia supplemented with ether, muscle relaxants, or opioids should be used instead of halothane.(3,4) Epinephrine may safely be used subcutaneously with the following precautions: the patient is adequately ventilated to prevent hypoxia or respiratory acidosis; the total dose of epinephrine is limited to 100 mcg/10 minute period or 300 mcg/hour in adults, 3.5 mcg/Kg in infants, 2.5 mcg/Kg in children up to two years of age, and 1.45 mcg/Kg in children over two years of age; a minimum effective concentration of anesthetic is maintained; the drugs are not co-administered in patients with hypertension or other cardiovascular disorders; and the cardiac rhythm is continuously monitored during and after injection.(3-10) If arrhythmias occur after the administration of the epinephrine, the drugs of choice are lidocaine or propranolol, depending on the type of arrhythmia.(1) DISCUSSION: Administration of epinephrine during halothane anesthesia may may lead to serious ventricular arrhythmias.(3-6,11-18) This has occurred when epinephrine was administered intravenously,(6) when it was administered with lidocaine as a dental block,(11,14) or when it was administered supraperiosteally.(5) Norepinephrine has been shown to interact with halothane in a manner similar to epinephrine.(1) In two case reports, patients were given terbutaline (0.25 to 0.35 mg) for wheezing following induction of anesthesia with halothane. One patient's heart rate increased from 68 to 100 beats/minute, and the ECG showed premature ventricular contractions and bigeminy, while the other patient developed multiple unifocal premature ventricular contractions and bigeminy. The arrhythmias resolved in both patients following lidocaine administration.(19) Although not documented, isoproterenol causes effects on the heart similar to terbutaline(20) and would probably interact with halothane in a similar manner. Other inhalation anesthetics that increase the incidence of arrhythmias with epinephrine include chloroform,(20) methoxyflurane,(20) and enflurane.(12) A similar interaction may be expected between the other inhalation anesthetics and sympathomimetics. |
DESFLURANE, FORANE, ISOFLURANE, SEVOFLURANE, SUPRANE, TERRELL, ULTANE |
| Solid Oral Potassium Tablets/Anticholinergics SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Concentrated potassium may damage the lining of the GI tract. Anticholinergics delay gastric emptying, resulting in the potassium product remaining in the gastrointestinal tract for a longer period of time.(1-16) CLINICAL EFFECTS: Use of solid oral dosage forms of potassium in patients treated with anticholinergics may result in gastrointestinal erosions, ulcers, stenosis and bleeding.(1-16) PREDISPOSING FACTORS: Diseases or conditions which may increase risk for GI damage include: preexisting dysphagia, strictures, cardiomegaly, diabetic gastroparesis, elderly status, or insufficient oral intake to allow dilution of potassium.(1-10,21) Other drugs which may add to risk for GI damage include: nonsteroidal anti-inflammatory drugs (NSAIDs), bisphosphonates, or tetracyclines.(21) PATIENT MANAGEMENT: Regulatory agency and manufacturer recommendations regarding this interaction: - In the US, all solid oral dosage forms (including tablets and extended release capsules) of potassium are contraindicated in patients receiving anticholinergics at sufficient dosages to result in systemic effects.(2-8) Patients receiving such anticholinergic therapy should use a liquid form of potassium chloride.(2) - In Canada, solid oral potassium is contraindicated in any patient with a cause for arrest or delay in tablet/capsule passage through the gastrointestinal tract and the manufacturers recommend caution with concurrent anticholinergic medications.(1,9-10) Evaluate each patient for predisposing factors which may increase risk for GI damage. In patients with multiple risk factors for harm, consider use of liquid potassium supplements, if tolerated. For patients receiving concomitant therapy, assure any potassium dose form is taken after meals with a large glass of water or other fluid. To decrease potassium concentration in the GI tract, limit each dose to 20 meq; if more than 20 meq daily is required, give in divided doses.(2) If concurrent therapy is warranted, monitor patients receiving concurrent therapy for signs of blood loss, including decreased hemoglobin, hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. Patients should be instructed to immediately report any difficulty swallowing, abdominal pain, distention, severe vomiting, or gastrointestinal bleeding. Instruct patients to report any signs and symptoms of bleeding, such as unusual bleeding from the gums or nose; unusual bruising; red or black, tarry stools; red, pink or dark brown urine; acute abdominal or joint pain and/or swelling. DISCUSSION: In clinical trials, there was a higher incidence of gastric and duodenal lesions in patients receiving a high dose of a wax-matrix controlled-release formulation with a concurrent anticholinergic agent. Some lesions were asymptomatic and not accompanied by bleeding, as shown by a lack of positive Hemoccult tests.(1-17) Several studies suggest that the incidence of gastric and duodenal lesions may be less with the microencapsulated formulation of potassium chloride.(14-17) |
KLOR-CON 10, KLOR-CON 8, KLOR-CON M10, KLOR-CON M15, KLOR-CON M20, POTASSIUM CHLORIDE, POTASSIUM CITRATE ER, UROCIT-K |
| Solid Oral Potassium Capsules/Anticholinergics SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Concentrated potassium may damage the lining of the GI tract. Anticholinergics delay gastric emptying, resulting in the potassium product remaining in the gastrointestinal tract for a longer period of time.(1-16)) CLINICAL EFFECTS: Use of solid oral dosage forms of potassium in patients treated with anticholinergics may result in gastrointestinal erosions, ulcers, stenosis and bleeding.(1-16) PREDISPOSING FACTORS: Diseases or conditions which may increase risk for GI damage include: preexisting dysphagia, strictures, cardiomegaly, diabetic gastroparesis, elderly status, or insufficient oral intake to allow dilution of potassium.(1-10,21) Other drugs which may add to risk for GI damage include: nonsteroidal anti-inflammatory drugs (NSAIDs), bisphosphonates, or tetracyclines.(21) PATIENT MANAGEMENT: Regulatory agency and manufacturer recommendations regarding this interaction: - In the US, all solid oral dosage forms (including tablets and extended release capsules) of potassium are contraindicated in patients receiving anticholinergics at sufficient dosages to result in systemic effects.(2-8) Patients receiving such anticholinergic therapy should use a liquid form of potassium chloride.(2) - In Canada, solid oral potassium is contraindicated in any patient with a cause for arrest or delay in tablet/capsule passage through the gastrointestinal tract and the manufacturers recommend caution with concurrent anticholinergic medications.(1,9-10) Evaluate each patient for predisposing factors which may increase risk for GI damage. In patients with multiple risk factors for harm, consider use of liquid potassium supplements, if tolerated. For patients receiving concomitant therapy, assure any potassium dose form is taken after meals with a large glass of water or other fluid. To decrease potassium concentration in the GI tract, limit each dose to 20 meq; if more than 20 meq daily is required, give in divided doses.(2) If concurrent therapy is warranted, monitor patients receiving concurrent therapy for signs of blood loss, including decreased hemoglobin, hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. Patients should be instructed to immediately report any difficulty swallowing, abdominal pain, distention, severe vomiting, or gastrointestinal bleeding. Instruct patients to report any signs and symptoms of bleeding, such as unusual bleeding from the gums or nose; unusual bruising; red or black, tarry stools; red, pink or dark brown urine; acute abdominal or joint pain and/or swelling. DISCUSSION: In clinical trials, there was a higher incidence of gastric and duodenal lesions in patients receiving a high dose of a wax-matrix controlled-release formulation with a concurrent anticholinergic agent. The lesions were asymptomatic and not accompanied by bleeding, as shown by a lack of positive Hemoccult tests.(1-17) Several studies suggest that the incidence of gastric and duodenal lesions may be less with the microencapsulated formulation of potassium chloride.(14-17) |
POTASSIUM CHLORIDE |
| Mixed & Indirect Sympathomimetics; Oral Phenylephrine/Selected MAOIs SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Catecholamine stores increased by MAOIs can be released by indirect acting sympathomimetics such as ephedrine and amphetamine. MAO inhibitors also interfere with gut and liver metabolism of direct acting sympathomimetics (e.g oral phenylephrine). CLINICAL EFFECTS: Concurrent use of MAOIs may result in potentiation of sympathomimetic effects, which may result in headaches, hypertensive crisis, toxic neurological effects, and malignant hyperpyrexia. Fatalities have occurred with combinations of sympathomimetics and MAO-A inhibitors. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Concurrent use of MAO-A inhibitors and sympathomimetics is contraindicated. The manufacturers of sympathomimetic agents recommend waiting 14 days after discontinuation of MAO inhibitors before initiating the sympathomimetic. Patients receiving indirect acting sympathomimetics should not receive linezolid unless they are monitored for potential increases in blood pressure. Initial dosages of dopamine should be reduced. At recommended dosages, oral selegiline and transdermal selegiline up to 6mg/day are selective for MAO-B; however, at higher dosages they have been shown to lose their selectivity. Patients receiving higher dosages of selegiline should be considered susceptive to this interaction. DISCUSSION: Indirect acting sympathomimetic amines may cause abrupt elevation of blood pressure when administered to patients taking monoamine oxidase inhibitors, resulting in a potentially fatal hypertensive crisis. Mixed (direct and indirect) acting sympathomimetics have also been shown to interact with monoamine oxidase inhibitors depending on their degree of indirect action. The direct-acting sympathomimetics have not been reported to interact. Dopamine is metabolized by monoamine oxidase, and its pressor effect is enhanced by monoamine oxidase inhibitors. Furazolidone, an antibacterial with monoamine oxidase inhibitor action, has also been shown to interact with indirect acting sympathomimetics. Foods containing large amounts of tyramine have also been implicated in this interaction. A significant pressor response was observed in normal subjects receiving linezolid and tyramine doses of more than 100 mg. Administration of linezolid (600 mg BID for 3 days) with pseudoephedrine (60 mg q 4 hours for 2 doses) increased blood pressure by 32 mmHg. Administration of linezolid (600 mg BID for 3 days) with phenylpropanolamine (25 mg q 4 hours for 2 doses) increased blood pressure by 38 mmHg. One or more of the drug pairs linked to this monograph have been included in a list of interactions that should be considered "high-priority" for inclusion and should not be inactivated in EHR systems. This DDI subset was vetted by an expert panel commissioned by the U.S. Office of the National Coordinator (ONC) for Health Information Technology. |
EMSAM, LINEZOLID, LINEZOLID-0.9% NACL, LINEZOLID-D5W, SELEGILINE HCL, XADAGO, ZELAPAR, ZYVOX |
| Radioactive Iodide/Agents that Affect Iodide SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1) CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1) PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less. PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(2) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(3) DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1) |
ADREVIEW, JEANATOPE, MEGATOPE, SODIUM IODIDE I-123, VOLUMEX |
| Selected Direct-Acting Sympathomimetics/Tricyclic Compounds SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Unknown. However, it is speculated that direct-acting sympathomimetic amines have an enhanced effect due to tricyclic blockage of norepinephrine reuptake. CLINICAL EFFECTS: Increased effect of direct acting sympathomimetics. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Consider avoiding the concurrent use of direct-acting sympathomimetics and tricyclic compounds. If concurrent use of direct-acting sympathomimetics and tricyclic compounds is warranted, the initial dose of the sympathomimetic should be lowered and the patient should be monitored for adverse cardiovascular effects. Use of tricyclic compounds and other sympathomimetics should be approached with caution. DISCUSSION: Epinephrine and other direct-acting sympathomimetic amines exert enhanced cardiovascular effects (e.g., arrhythmias, hypertension, and tachycardia) in individuals concurrently receiving or previously treated with tricyclic antidepressants. Other direct and mixed acting sympathomimetic amines have also been reported to interact with tricyclic antidepressants. These include norepinephrine, phenylephrine, dopamine, and methoxamine. Protriptyline, amitriptyline, and desipramine have also been reported to interact with direct-acting sympathomimetics. |
AMITRIPTYLINE HCL, AMOXAPINE, ANAFRANIL, CHLORDIAZEPOXIDE-AMITRIPTYLINE, CLOMIPRAMINE HCL, DESIPRAMINE HCL, DOXEPIN HCL, IMIPRAMINE HCL, IMIPRAMINE PAMOATE, NORPRAMIN, NORTRIPTYLINE HCL, PAMELOR, PERPHENAZINE-AMITRIPTYLINE, PROTRIPTYLINE HCL, SILENOR, TRIMIPRAMINE MALEATE |
| Iobenguane I 123/Agents that Affect Catecholamines SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Many compounds that reduce catecholamine uptake or that deplete catecholamine stores may interfere with iobenguane uptake into cells.(1) CLINICAL EFFECTS: Compounds that reduce catecholamine uptake or that deplete catecholamine stores may interfere with imaging completed with iobenguane.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Discuss the use of agents that affect catecholamines. Discontinue drugs that reduce catecholamine uptake or deplete catecholamine stores prior to imaging with iobenguane. Before imaging with iobenguane, discontinue agents that affect catecholamines for at least 5 biological half-lives, as clinically tolerated.(1) DISCUSSION: Many agents may reduce catecholamine uptake or deplete catecholamine stores.(1) Examples include: - CNS stimulants or amphetamines (e.g. cocaine, methylphenidate, dextroamphetamine) - norepinephrine and dopamine reuptake inhibitors (e.g. phentermine) - norepinephrine and serotonin reuptake inhibitors (e.g. tramadol) - monoamine oxidase inhibitors (e.g. phenelzine, linezolid) - central monoamine depleting drugs (e.g. reserpine) - non-select beta adrenergic blocking drugs (e.g. labetalol) - alpha agonists or alpha/beta agonists (e.g. pseudoephedrine, phenylephrine, ephedrine, phenylpropanolamine, naphazoline) - tricyclic antidepressants or norepinephrine reuptake inhibitors (e.g. amitriptyline, bupropion, duloxetine, mirtazapine, venlafaxine) - botanicals that may inhibit reuptake of norepinephrine, serotonin or dopamine (e.g. ephedra, ma huang, St. John's Wort, yohimbine) |
ADREVIEW |
| Selected CYP2D6 Substrates/Panobinostat SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Panobinostat is a moderate inhibitor of CYP2D6 and is expected to inhibit the metabolism of agents through this pathway.(1) CLINICAL EFFECTS: Concurrent use of panobinostat may result in elevated levels of and toxicity from agents metabolized by CYP2D6.(1) PREDISPOSING FACTORS: With tricyclic antidepressants, the risk of seizures may be increased in patients with a history of head trauma or prior seizure; CNS tumor; severe hepatic cirrhosis; excessive use of alcohol or sedatives; addiction to opiates, cocaine, or stimulants; use of over-the-counter stimulants and anorectics; diabetics treated with oral hypoglycemics or insulin; or with concomitant medications known to lower seizure threshold (antipsychotics, theophylline, systemic steroids). With anticholinergic agents, the risk of anticholinergic toxicities including cognitive decline, delirium, falls and fractures is increased in geriatric patients using more than one medicine with anticholinergic properties.(4) PATIENT MANAGEMENT: Avoid the concurrent use of panobinostat with agents that are sensitive CYP2D6 or CYP2D6 substrates with a narrow therapeutic index. If concurrent use is warranted, monitor patients for toxicity.(1) DISCUSSION: In a study in 14 subjects with advanced cancer, panobinostat (20 mg daily on Days 3, 5, and 8) increased the maximum concentration (Cmax) and area-under-curve (AUC) of a single dose of dextromethorphan (60 mg) by 20-200% and 20-130%, respectively. Dextromethorphan exposures were extremely variable.(1) Selected CYP2D6 substrates linked to this monograph include: desipramine, deutetrabenazine, dextromethorphan, doxepin, encainide, methoxyphenamine, metoprolol, nebivolol, paroxetine, perphenazine, risperidone, tetrabenazine, trimipramine, venlafaxine, and yohimbine. |
FARYDAK |
| Selected CYP1A2 or CYP2D6 Substrates/Givosiran SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Givosiran interferes with the first and rate-limiting step in hepatic heme biosynthesis, which may lower hepatic heme levels and decrease production and/or activity of cytochrome P450 enzymes.(1,2) CLINICAL EFFECTS: Concurrent use of givosiran may result in elevated levels of and toxicity from agents metabolized by CYP1A2 or CYP2D6.(1) PREDISPOSING FACTORS: With tricyclic antidepressants, the risk of seizures may be increased in patients with a history of head trauma or prior seizure; CNS tumor; severe hepatic cirrhosis; excessive use of alcohol or sedatives; addiction to opiates, cocaine, or stimulants; use of over-the-counter stimulants and anorectics; diabetics treated with oral hypoglycemics or insulin; or with concomitant medications known to lower seizure threshold (antipsychotics, theophylline, systemic steroids). With anticholinergic agents, the risk of anticholinergic toxicities including cognitive decline, delirium, falls and fractures is increased in geriatric patients using more than one medicine with anticholinergic properties.(3) PATIENT MANAGEMENT: Avoid the concurrent use of givosiran with agents that are sensitive substrates of CYP1A2 or CYP2D6, or CYP1A2 or CYP2D6 substrates with a narrow therapeutic index. If concurrent use is unavoidable, decrease the dose of the CYP1A2 or CYP2D6 substrate and monitor patients for toxicity. DISCUSSION: A study of 9 patients with acute intermittent porphyria found that givosiran decreased the maximum concentration (Cmax) and area-under-curve (AUC) of caffeine (a CYP1A2 substrate) by 1.3- and 3.1-fold, respectively, compared to caffeine alone. Givosiran also decreased the Cmax and AUC of dextromethorphan (a CYP2D6 substrate) by 2- and 2.4-fold, respectively, compared to dextromethorphan alone.(1,2) Selected CYP2D6 substrates linked to this monograph include: desipramine, deutetrabenazine, dextromethorphan, doxepin, encainide, methoxyphenamine, metoprolol, nebivolol, nefazodone, paroxetine, perphenazine, risperidone, tetrabenazine, trimipramine, and venlafaxine. Selected CYP1A2 substrates linked to this monograph include: agomelatine, aminophylline, rasagiline, tacrine, theophylline, tizanidine, and yohimbine. |
GIVLAARI |
| Clozapine/Anticholinergics SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Clozapine has potent anticholinergic properties and inhibits serotonin receptors, including 5-HT3.(1-4) Both of these properties may cause inhibition of gastrointestinal (GI) smooth muscle contraction, resulting in decreased peristalsis.(3,4) These effects may be compounded by concurrent use of anticholinergic agents.(1-6) CLINICAL EFFECTS: Concurrent use of clozapine with other anticholinergic agents may increase the risk of constipation (common) and serious bowel complications (uncommon), including complete bowel obstruction, fecal impaction, paralytic ileus and intestinal ischemia or infarction.(1-6) PREDISPOSING FACTORS: The risk for serious bowel complications is higher with increasing age, higher frequency of constipation, and in patients on higher doses of clozapine or multiple anticholinergic agents.(1,5) PATIENT MANAGEMENT: Avoid the use of other anticholinergic agents with clozapine.(1-6) If concurrent use is necessary, evaluate the patient's bowel function regularly. Monitor for symptoms of constipation and GI hypomotility, including having bowel movements less than three times weekly or less than usual, difficulty having a bowel movement or passing gas, nausea, vomiting, and abdominal pain or distention.(2) Consider a prophylactic laxative in those with a history of constipation or bowel obstruction.(2) Review patient medication list for other anticholinergic agents. When possible, decrease the dosage or number of prescribed anticholinergic agents, particularly in the elderly. Counsel the patient about the importance of maintaining adequate hydration. Encourage regular exercise and eating a high-fiber diet.(2) DISCUSSION: In a prospective cohort study of 26,720 schizophrenic patients in the Danish Central Psychiatric Research Registry, the odds ratio (OR) for ileus was 1.99 with clozapine and 1.48 with anticholinergics. The OR for fatal ileus was 6.73 with clozapine and 5.88 with anticholinergics. Use of anticholinergics with 1st generation antipsychotics (FGA) increased the risk of ileus compare to FGA alone, but this analysis was not done with clozapine.(5) A retrospective cohort study of 24,970 schizophrenic patients from the Taiwanese National Health Insurance Research Database found that the hazard ratio (HR) for clozapine-induced constipation increased from 1.64 when clozapine is used alone, to 2.15 when used concomitantly with anticholinergics. However, there was no significant difference in the HR for ileus when clozapine is used with and without anticholinergics (1.95 and 2.02, respectively).(6) In the French Pharmacovigilance Database, 7 of 38 cases of antipsychotic-associated ischemic colitis or intestinal necrosis involved clozapine, and 5 of these cases involved use of concomitant anticholinergic agents. Three patients died, one of whom was on concomitant anticholinergics.(3) In a case series, 4 of 9 cases of fatal clozapine-associated GI dysfunction involved concurrent anticholinergic agents.(4) |
CLOZAPINE, CLOZAPINE ODT, CLOZARIL, VERSACLOZ |
| Eluxadoline/Anticholinergics; Opioids SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Eluxadoline is a mixed mu-opioid and kappa-opioid agonist and delta-opioid antagonist and may alter or slow down gastrointestinal transit.(1) CLINICAL EFFECTS: Constipation related adverse events that sometimes required hospitalization have been reported, including the development of intestinal obstruction, intestinal perforation, and fecal impaction.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Avoid use with other drugs that may cause constipation. If concurrent use is necessary, evaluate the patient's bowel function regularly. Monitor for symptoms of constipation and GI hypomotility, including having bowel movements less than three times weekly or less than usual, difficulty having a bowel movement or passing gas, nausea, vomiting, and abdominal pain or distention.(1) Instruct patients to stop eluxadoline and immediately contact their healthcare provider if they experience severe constipation. Loperamide may be used occasionally for acute management of severe diarrhea, but must be discontinued if constipation develops.(1) DISCUSSION: In phase 3 clinical trials, constipation was the most commonly reported adverse reaction (8%). Approximately 50% of constipation events occurred within the first 2 weeks of treatment while the majority occurred within the first 3 months of therapy. Rates of severe constipation were less than 1% in patients receiving eluxadoline doses of 75 mg and 100 mg.(1) |
VIBERZI |
| Mixed & Indirect Sympathomimetics; Oral Phenylephrine/Rasagiline SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Catecholamine stores increased by MAOIs can be released by indirect acting sympathomimetics such as ephedrine and amphetamine. MAO inhibitors also interfere with gut and liver metabolism of direct acting sympathomimetics (e.g oral phenylephrine). CLINICAL EFFECTS: Concurrent use of MAOIs may result in potentiation of sympathomimetic effects, which may result in headaches, hypertensive crisis, toxic neurological effects, and malignant hyperpyrexia. Hypertensive crisis has been reported in patients taking recommended doses of rasagiline with sympathomimetic agents. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: At recommended dosages, rasagiline is selective for MAO-B; however, at higher dosages it has been shown to lose its selectivity. Patients receiving higher dosages of rasagiline should be considered susceptive to this interaction. Concurrent use should be approached with caution. DISCUSSION: Indirect acting sympathomimetic amines may cause abrupt elevation of blood pressure when administered to patients taking monoamine oxidase inhibitors, resulting in a potentially fatal hypertensive crisis. Mixed (direct and indirect) acting sympathomimetics have also been shown to interact with monoamine oxidase inhibitors depending on their degree of indirect action. The direct-acting sympathomimetics have not been reported to interact. Dopamine is metabolized by monoamine oxidase, and its pressor effect is enhanced by monoamine oxidase inhibitors. |
AZILECT, RASAGILINE MESYLATE |
| Glucagon (Diagnostic)/Anticholinergics SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Glucagon and anticholinergic agents may have additive effects on inhibition of gastrointestinal motility.(1) CLINICAL EFFECTS: Concurrent use of glucagon with anticholinergic agents may increase the risk of gastrointestinal hypomotility, including constipation and bowel complications.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Concurrent use of glucagon as a diagnotic aid is not recommended with the use of anticholinergic agents.(1) If concurrent use is necessary, evaluate the patient's bowel function. Monitor for symptoms of constipation and gastrointestinal hypomotility. DISCUSSION: Both glucagon and anticholinergic agents may have additive effects on inhibition of gastrointestinal motility and increase the risk of gastrointestinal adverse effects.(1) |
GLUCAGON HCL, GVOKE VIALDX |
| Sodium Iodide I 131/Agents that Affect Iodide SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Many compounds can affect iodide protein binding and alter iodide pharmacokinetics and pharmacodynamics.(1,2) CLINICAL EFFECTS: Compounds that affect iodide pharmacokinetics and pharmacodynamics may impact the effectiveness of radioactive iodide.(1,2) PREDISPOSING FACTORS: Compounds that affect iodide pharmacokinetics and pharmacodynamics are expected to have the most impact during therapy using radioactive iodide. Diagnostic procedures would be expected to be impacted less. PATIENT MANAGEMENT: Discuss the use of agents that affect iodide pharmacokinetics and pharmacodynamics with the patient's oncologist.(1,2) Because indocyanine green contains sodium iodide, the iodine-binding capacity of thyroid tissue may be reduced for at least one week following administration. Do not perform radioactive iodine uptake studies for at least one week following administration of indocyanine green.(3) The manufacturer of iopamidol states administration may interfere with thyroid uptake of radioactive iodine and decrease therapeutic and diagnostic efficacy. Avoid thyroid therapy or testing for up to 6 weeks post administration of iopamidol.(4) DISCUSSION: Many agents interact with radioactive iodine. The average duration of effect is: anticoagulants - 1 week antihistamines - 1 week anti-thyroid drugs, e.g: carbimazole, methimazole, propylthiouracil - 3-5 days corticosteroids - 1 week iodide-containing medications, e.g: amiodarone - 1-6 months expectorants - 2 weeks Lugol solution - 3 weeks saturated solution of potassium iodine - 3 weeks vitamins - 10-14 days iodide-containing X-ray contrast agents - up to 1 year lithium - 4 weeks phenylbutazone - 1-2 weeks sulfonamides - 1 week thyroid hormones (natural or synthetic), e.g.: thyroxine - 4 weeks tri-iodothyronine - 2 weeks tolbutamide - 1 week topical iodide - 1-9 months (1,2) |
HICON, SODIUM IODIDE I-131 |
There are 14 moderate interactions.
The clinician should assess the patient’s characteristics and take action as needed. Actions required for moderate interactions include, but are not limited to, discontinuing one or both agents, adjusting dosage, altering administration.
| Drug Interaction | Drug Names |
|---|---|
| Sympathomimetics (Direct, Mixed-Acting)/Guanethidine SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Direct or mixed-acting sympathomimetics may inhibit uptake of guanethidine at the adrenergic neuron. CLINICAL EFFECTS: Decreased antihypertensive effectiveness. Effects may be seen for several days after discontinuation of the direct or mixed-acting sympathomimetic. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Avoid concomitant administration of these drugs. If both drugs are administered, adjust the guanethidine dose as needed based on blood pressure. DISCUSSION: Documentation supports routine monitoring of this interaction. It should be noted that this interaction can occur quickly. |
GUANETHIDINE HEMISULFATE |
| Sympathomimetics/Rauwolfia Alkaloids SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Reserpine depletes catecholamine stores within the peripheral vascular adrenergic nerve endings, thus indirect acting sympathomimetics are unable to trigger the release of catecholamines. The reserpine-induced catecholamine release increases sensitivity to the effects of direct acting sympathomimetics. CLINICAL EFFECTS: Increased effects of direct acting sympathomimetics. Decreased effects of indirect acting sympathomimetics. Mixed acting sympathomimetics will show effects based on the predominance of either direct or indirect activity. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: If these agents are administered concurrently, monitor blood pressure. The dose of the sympathomimetic may need to be adjusted. DISCUSSION: This interaction has been well documented in animal studies and human case reports have confirmed the interaction. Reserpine has been shown to decrease the response to epinephrine administered for hypotension. Reserpine has also been shown to decrease the effectiveness of ophthalmic epinephrine, a direct acting sympathomimetic. Ophthalmic phenylephrine has been shown to decrease the hypotensive effects of reserpine. |
RESERPINE |
| Sympathomimetics (Direct, Mixed-Acting)/Methyldopa SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Unknown. CLINICAL EFFECTS: The pressor response to sympathomimetics may be increased. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Start with low doses of sympathomimetics and monitor blood pressure of patients during concurrent administration of sympathomimetics and methyldopa. DISCUSSION: The pressor response to sympathomimetics has been reported to be increased during methyldopa administration. In addition to increased duration of pressor response, severe hypertension has been reported. |
METHYLDOPA, METHYLDOPA-HYDROCHLOROTHIAZIDE, METHYLDOPATE HCL |
| Tamoxifen/Selected Weak CYP2D6 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Inhibitors of CYP2D6 may inhibit the conversion of tamoxifen to endoxifen (an active metabolite of tamoxifen).(1-2) The role of endoxifen in tamoxifen's efficacy has been debated and may involve a minimum concentration level.(3-5) CLINICAL EFFECTS: Concurrent use of inhibitors of CYP2D6 may decrease the effectiveness of tamoxifen in preventing breast cancer recurrence. PREDISPOSING FACTORS: Concurrent use of weak CYP2D6 inhibitors in patients who are CYP2D6 intermediate metabolizers should be avoided. Patients who are CYP2D6 poor metabolizers lack CYP2D6 function and are not affected by CYP2D6 inhibition. PATIENT MANAGEMENT: Although data on this interaction are conflicting, it may be prudent to use alternatives to CYP2D6 inhibitors when possible in patients taking tamoxifen. The US manufacturer of tamoxifen states that the impact on the efficacy of tamoxifen by strong CYP2D6 inhibitors is uncertain and makes no recommendation regarding coadministration with inhibitors of CYP2D6.(12) The manufacturer of paroxetine (a strong CYP2D6 inhibitor) states that alternative agents with little or no CYP2D6 inhibition should be considered.(13) The National Comprehensive Cancer Network's breast cancer guidelines advises caution when coadministering strong CYP2D6 inhibitors with tamoxifen.(14) If concurrent therapy is warranted, the risks versus benefits should be discussed with the patient. DISCUSSION: Some studies have suggested that administration of fluoxetine, paroxetine, and quinidine with tamoxifen or a CYP2D6 poor metabolizer phenotype may result in a decrease in the formation of endoxifen (an active metabolite of tamoxifen) and a shorter time to breast cancer recurrence.(1-2,9) A retrospective study of 630 breast cancer patients found an increasing risk of breast cancer mortality with increasing durations of coadministration of tamoxifen and paroxetine. In the adjusted analysis, absolute increases of 25%, 50%, and 75% in the proportion of time of overlapping use of tamoxifen with paroxetine was associated with 24%, 54%, and 91% increase in the risk of death from breast cancer, respectively.(16) The CYP2D6 genotype of the patient may have a role in the effects of this interaction. Patients with wild-type CYP2D6 genotype may be affected to a greater extent by this interaction. Patients with a variant CYP2D6 genotype may have lower baseline levels of endoxifen and may be affected to a lesser extent by this interaction.(6-10) In a retrospective review, 1,325 patients treated with tamoxifen for breast cancer were classified as being poor 2D6 metabolizers (lacking functional CYP2D6 enzymes), intermediate metabolizers (heterozygous alleles), or extensive metabolizers (possessing 2 functional alleles). After a mean follow-up period of 6.3 years, the recurrence rates were 14.9%, 20.9%, and 29.0%, in extensive metabolizers, intermediate metabolizers, and poor metabolizers, respectively.(11) In October of 2006, the Advisory Committee Pharmaceutical Science, Clinical Pharmacology Subcommittee of the US Food and Drug Administration recommended that the US tamoxifen labeling be updated to include information about the increased risk of breast cancer recurrence in poor CYP2D6 metabolizers (either by genotype or drug interaction).(17-18) The labeling changes were never made due to ongoing uncertainty about the effects of CYP2D6 genotypes on tamoxifen efficacy. In contrast to the above information, two studies have shown no relationship between CYP2D6 genotype and breast cancer outcome.(19-21) As well, a number of studies found no association between use of CYP2D6 inhibitors and/or antidepressants in patients on tamoxifen and breast cancer recurrence,(22-26) though the studies were limited by problematic selection of CYP2D6 inhibitors and short follow-up. Weak inhibitors of CYP2D6 include: alogliptin, artesunate, celecoxib, chloroquine, cimetidine, clobazam, clomipramine, cobicistat, delavirdine, diltiazem, dimenhydrinate, diphenhydramine, dronabinol, dupilumab, echinacea, enasidenib, fedratinib, felodipine, fluvoxamine, gefitinib, hydralazine, imatinib, labetalol, lorcaserin, nicardipine, osilodrostat, ranitidine, ritonavir, sertraline, verapamil and viloxazine.(27) |
SOLTAMOX, TAMOXIFEN CITRATE |
| Dextromethorphan/Selected SSRIs that Inhibit CYP2D6 SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Fluoxetine and paroxetine, strong inhibitors of CYP2D6, may inhibit the metabolism of dextromethorphan.(1-4) CLINICAL EFFECTS: Patients may experience increased adverse effects of dextromethorphan due to elevated systemic concentrations. Concomitant use of two or more serotonergic agents increases the risk for serotonin syndrome. Serotonin syndrome constitutes a range of toxicities from mild to life threatening.(5) Mild serotonin symptoms may include: shivering, diaphoresis, mydriasis, intermittent tremor, and/or myoclonus.(5) Moderate serotonin symptoms may include: tachycardia, hypertension, hyperthermia, mydriasis, diaphoresis, hyperactive bowel sounds, hyperreflexia, and/OR clonus.(5) Severe serotonin symptoms may include: severe hypertension and tachycardia, shock, agitated delirium, muscular rigidity, and/or hypertonicity.(5) PREDISPOSING FACTORS: Concurrent use of additional drugs which increase CNS serotonin levels would be expected to further increase risk for serotonin syndrome.(5) PATIENT MANAGEMENT: Monitor patients on multiple serotonergic agents for symptoms of serotonin toxicity. Patients in whom serotonin syndrome is suspected should receive immediate medical attention. If the interacting agents are prescribed by different providers, it would be prudent to assure that both are aware of concomitant therapy and monitoring the patient for serotonin toxicities. Advise patients not to exceed recommended dosages of dextromethorphan. If concurrent therapy is warranted, patients should be monitored for signs and symptoms of serotonin syndrome. Instruct patients to report muscle twitching, tremors, shivering and stiffness, fever, heavy sweating, heart palpitations, restlessness, confusion, agitation, trouble with coordination, or severe diarrhea. DISCUSSION: An open label parallel group trial evaluated the interaction between dextromethorphan-quinidine 30 mg-30 mg (higher than marketed strength of 20 mg-10 mg) and paroxetine 20 mg in 27 healthy volunteers with a mean age of 33.6 years. Subjects were randomly divided into 2 groups: - Group 1 received paroxetine 20 mg once daily for 12 days, followed by the addition of dextromethorphan-quinidine twice daily for 8 days. - Group 2 received dextromethorphan-quinidine twice daily for 8 days, followed by paroxetine 20 mg daily for 12 days. Results: overall, adverse effects were reported in 19 of 26 subjects who received combination therapy (73%) and 15 of 27 subjects who received monotherapy (56%). Adverse effects from the combination differed somewhat between groups and were more closely associated with the second drug product administered. Group 1 reported dizziness, headache, somnolence, euphoria, nausea, and vomiting after the addition of dextromethorphan-quinidine to paroxetine. Group 2 adverse events were dizziness, headache, nausea, vomiting, insomnia, anxiety, and hyperhidrosis after the addition of paroxetine to dextromethorphan.(1) Two weeks of fluoxetine therapy increased the area-under-curve (AUC) of dextromethorphan by 27-fold.(4) Serotonin syndrome has been reported in patients following the addition of dextromethorphan containing cough syrups to fluoxetine(6,7) and paroxetine.(8) |
FLUOXETINE DR, FLUOXETINE HCL, OLANZAPINE-FLUOXETINE HCL, PAROXETINE CR, PAROXETINE ER, PAROXETINE HCL, PAROXETINE MESYLATE, PAXIL, PAXIL CR, PROZAC |
| Selected CYP2D6 Substrates/Desvenlafaxine SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Desvenlafaxine is considered a weak inhibitor of CYP2D6.(1) CLINICAL EFFECTS: Concurrent use of desvenlafaxine may lead to increased serum levels and adverse effects of drugs sensitive to inhibition of the CYP2D6 pathway.(1) Agents linked to this monograph are: atomoxetine, dapoxetine, deutetrabenazine, dextromethorphan, metoprolol, nebivolol, perphenazine, tolterodine, and yohimbine. PREDISPOSING FACTORS: With perphenazine and tolterodine, the risk of anticholinergic toxicities including cognitive decline, delirium, falls and fractures is increased in geriatric patients using more than one medicine with anticholinergic properties.(2) PATIENT MANAGEMENT: Reduce the dose of CYP2D6 substrates by up to one-half when coadministered with desvenlafaxine 400 mg.(1) Studies have shown that desvenlafaxine does not have a clinically relevant effect on CYP2D6 metabolism at the dose of 100 mg daily. CYP2D6 substrates should be dosed at the original level when coadministered with desvenlafaxine 100 mg or lower or when desvenlafaxine is discontinued.(1) DISCUSSION: In a study, coadministration of desvenlafaxine 100 mg daily with desipramine (single dose 50 mg) increased desipramine's maximum concentration (Cmax) and area-under-the-curve (AUC)by 25% and 17%.(1) In a study, coadministration of desvenlafaxine 400 mg daily with desipramine (single dose 50 mg) increased desipramine's maximum concentration (Cmax) and area-under-the-curve (AUC)by 50% and 90%.(1) Selected CYP2D6 substrates linked to this monograph are: atomoxetine, dapoxetine, deutetrabenazine, dextromethorphan, metoprolol, nebivolol, perphenazine, tolterodine, and yohimbine. |
DESVENLAFAXINE ER, DESVENLAFAXINE SUCCINATE ER, PRISTIQ |
| Eliglustat/Weak CYP2D6 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Weak inhibitors of CYP2D6 may inhibit the metabolism of eliglustat. If the patient is also taking an inhibitor of CYP3A4, eliglustat metabolism can be further inhibited.(1) CLINICAL EFFECTS: Concurrent use of an agent that is a weak inhibitor of CYP2D6 may result in elevated levels of and clinical effects of eliglustat, including prolongation of the PR, QTc, and/or QRS intervals, which may result in life-threatening cardiac arrhythmias.(1) PREDISPOSING FACTORS: If the patient is also taking an inhibitor of CYP3A4 and/or has hepatic impairment, eliglustat metabolism can be further inhibited.(1) The risk of QT prolongation or torsades de pointes may be increased in patients with cardiovascular disease (e.g. heart failure, myocardial infarction, history of torsades de pointes, congenital long QT syndrome), hypokalemia, hypomagnesemia, hypocalcemia, bradycardia, female gender, or advanced age.(2) Concurrent use of more than one drug known to cause QT prolongation or higher systemic concentrations of either QT prolonging drug are additional risk factors for torsades de pointes. Factors which may increase systemic drug concentrations include rapid infusion of an intravenous dose or impaired metabolism or elimination of the drug (e.g. coadministration with an agent which inhibits its metabolism or elimination, genetic impairment in drug metabolism or elimination, and/or renal/hepatic dysfunction).(2) PATIENT MANAGEMENT: The dosage of eliglustat with weak inhibitors of CYP2D6 in poor CYP2D6 metabolizers should be limited to 84 mg daily.(1) The dosage of eliglustat with weak inhibitors of CYP2D6 in extensive CYP2D6 metabolizers with mild (Child-Pugh Class A) hepatic impairment should be limited to 84 mg daily.(1) If concurrent therapy is warranted, consider obtaining serum calcium, magnesium, and potassium levels and monitoring ECG at baseline and at regular intervals. Correct any electrolyte abnormalities. Instruct patients to report any irregular heartbeat, dizziness, or fainting. DISCUSSION: Paroxetine (30 mg daily), a strong inhibitor of CYP2D6, increased eliglustat (84 mg BID) maximum concentration (Cmax) and area-under-curve (AUC) by 7-fold and 8.4-fold, respectively, in extensive metabolizers. Physiologically-based pharmacokinetic (PKPB) models suggested paroxetine would increase eliglustat Cmax and AUC by 2.1-fold and 2.3-fold, respectively, in intermediate metabolizers. PKPB models suggested ketoconazole may increase the Cmax and AUC of eliglustat (84 mg daily) by 4.3-fold and 6.2-fold, respectively, in poor metabolizers.(1) PKPB models suggested terbinafine, a moderate inhibitor of CYP2D6, would increase eliglustat Cmax and AUC by 3.8-fold and 4.5-fold, respectively, in extensive metabolizers and by 1.6-fold and 1.6-fold, respectively in intermediate metabolizers. PKPB models suggest that concurrent eliglustat (84 mg BID), paroxetine (a strong inhibitor of CYP2D6), and ketoconazole would increase eliglustat Cmax and AUC by 16.7-fold and 24.2-fold, respectively, in extensive metabolizers. In intermediate metabolizers, eliglustat Cmax and AUC would be expected to increase 7.5-fold and 9.8-fold, respectively.(1) PKPB models suggest that concurrent eliglustat (84 mg BID), terbinafine (a moderate inhibitor of CYP2D6), and ketoconazole would increase eliglustat Cmax and AUC by 10.2-fold and 13.6-fold, respectively, in extensive metabolizers. In intermediate metabolizers, eliglustat Cmax and AUC would be expected to increase 4.2-fold and 5-fold, respectively.(1) A single dose of rolapitant increased dextromethorphan, a CYP2D6 substrate, about 3-fold on days 8 and day 22 following administration. Dextromethorphan levels remained elevated by 2.3-fold on day 28 after single dose rolapitant. The inhibitory effects of rolapitant on CYP2D6 are expected to persist beyond 28 days.(5) Weak inhibitors of CYP2D6 include: alogliptin, artesunate, celecoxib, chloroquine, clobazam, clomipramine, desvenlafaxine, dimenhydrinate, diphenhydramine, dronabinol, dupilumab, echinacea, enasidenib, felodipine, gefitinib, hydralazine, hydroxychloroquine, lorcaserin, methadone, panobinostat, propafenone, sertraline, vemurafenib, and venlafaxine.(3,4) |
CERDELGA |
| Metoprolol/Selected CYP2D6 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: CYP2D6 inhibitors may inhibit the metabolism of metoprolol.(1,2) CLINICAL EFFECTS: Concurrent use of CYP2D6 inhibitors may result in elevated levels of and toxicity from metoprolol.(1,2) PREDISPOSING FACTORS: The interaction may be more severe in patients who are ultrarapid metabolizers of CYP2D6,(1,2) elderly,(3) and on higher doses of beta-blockers.(3) PATIENT MANAGEMENT: Monitor patients receiving concurrent therapy with metoprolol and inhibitors of CYP2D6. The dosage of metoprolol may need to be adjusted.(1,2) The effects of rolapitant, a moderate CYP2D6 inhibitor, on CYP2D6 are expected to last at least 28 days after administration.(4) DISCUSSION: In a case report, a patient maintained on metoprolol developed bradycardia following the addition of bupropion.(5) In a study in 20 healthy females, diphenhydramine increased the AUC of metoprolol by 21%. Heart rate reduction increased 29%.(6) In a randomized study in 16 healthy subjects, diphenhydramine decreased metoprolol oral and nonrenal clearance by 2-fold in extensive 2D6 metabolizers. In extensive 2D6 metabolizers, metoprolol-induced effects on heart rate, systolic blood pressure, and aortic blood flow peak velocity were all increased. There were no effects of diphenhydramine in poor metabolizers.(7) Fluoxetine has been shown to inhibit metoprolol metabolism in vitro.(8) There is a case report of severe bradycardia following the addition of fluoxetine to metoprolol.(9) In a 3-way, randomized, cross-over study in healthy subjects, paroxetine (20 mg daily) increased the area-under-curve (AUC) of both S- and R-metoprolol by 3-fold, and 4-fold, respectively, regardless of whether the formulation of metoprolol was immediate release or extended release. Concurrent paroxetine also significantly decreased heart rate and blood pressure when compared to metoprolol alone.(10) In an open-label, randomized, cross-over study in 10 healthy subjects, paroxetine increased the AUC of S-metoprolol and R-metoprolol from an immediate release formulation (50 mg)by 4-fold and 5-fold, respectively. Paroxetine increased the AUC of S-metoprolol and R-metoprolol from an extended release formulation (100 mg) by 3-fold and 4-fold, respectively.(11) In a study in patients with acute myocardial infarction and depression, paroxetine (20 mg daily) increased the AUC of metoprolol 3-fold. Mean heart rate was significantly lower following the addition of paroxetine to metoprolol. Two patients experienced bradycardia and severe orthostatic hypotension.(12) In an open trial in 8 healthy males, paroxetine (20 mg daily) increased the AUC of S-metoprolol and R-metoprolol by 4-fold and 7-fold, respectively.(13) There are case reports of complete atrioventricular block(14) and bradycardia(15) with concurrent metoprolol and paroxetine. A systematic review and meta-analysis of CYP2D6 interactions between metoprolol and either paroxetine or fluoxetine reviewed 9 articles including 4 primary and 2 observational studies as well as 3 case reports. Experimental studies noted paroxetine increased the AUC of metoprolol 3-fold to 5-fold and significantly decreased blood pressure and heart rate. Paroxetine and fluoxetine have shown equipotent inhibitor capacity on CYP2D6. The metabolite, norfluoxetine, is also an inhibitor of CYP2D6.(16) A retrospective cohort study evaluated morbidity in patients on a beta-blocker primarily metabolized by CYP2D6 (e.g., nebivolol, metoprolol, carvedilol, propranolol, labetalol) and started on a strong or moderate CYP2D6-inhibiting antidepressant (e.g., fluoxetine, paroxetine, bupropion, duloxetine). Use of such an antidepressant with a beta-blocker was associated with an increased risk of hospitalization or ED visit due to an adverse hemodynamic event (HR 1.53, 95% CI 1.03-2.81, p=0.04).(3) CYP2D6 inhibitors include: abiraterone, bupropion, celecoxib, cinacalcet, citalopram, dacomitinib, dimenhydrinate, diphenhydramine, duloxetine, escitalopram, fedratinib, fluoxetine, hydroxychloroquine, imatinib, lorcaserin, osilodrostat, paroxetine, ranitidine, ranolazine, rolapitant, and sertraline. One or more of the drug pairs linked to this monograph have been included in a list of interactions that could be considered for classification as "non-interruptive" in EHR systems. This DDI subset was vetted by an expert panel commissioned by the U.S. Office of the National Coordinator (ONC) for Health Information Technology. |
KAPSPARGO SPRINKLE, LOPRESSOR, METOPROLOL SUCCINATE, METOPROLOL TARTRATE, METOPROLOL-HYDROCHLOROTHIAZIDE, TOPROL XL |
| Zonisamide/Anticholinergics SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Zonisamide can cause decreased sweating and elevated body temperature. Agents with anticholinergic activity can predispose patients to heat-related disorders.(1-2) CLINICAL EFFECTS: Concurrent use of zonisamide with agents with anticholinergic activity may increase the incidence of oligohidrosis and hyperthermia, especially in pediatric or adolescent patients.(1-2) Overheating and dehydration can lead to brain damage and death. PREDISPOSING FACTORS: Pediatric and adolescent patients and patients with dehydration may be more likely to experience heat-related disorders.(1) PATIENT MANAGEMENT: The UK and US manufacturers of zonisamide state that caution should be used in adults when zonisamide is prescribed with other medicinal products that predispose to heat-related disorders, such as agents with anticholinergic activity.(1-2) Pediatric and adolescent patients must not take anticholinergic agents (e.g. clomipramine, hydroxyzine, diphenhydramine, haloperidol, imipramine, and oxybutynin) concurrently with zonisamide.(1) Monitor for signs and symptoms of heat stroke: skin feels very hot with little or no sweating, confusion, muscle cramps, rapid heartbeat, or rapid breathing. Monitor for signs and symptoms of dehydration: dry mouth, urinating less than usual, dark-colored urine, dry skin, feeling tired, dizziness, or irritability. If signs or symptoms of dehydration, oligohidrosis, or elevated body temperature occur, discontinuation of zonisamide should be considered. DISCUSSION: Case reports of decreased sweating and elevated temperature have been reported, especially in pediatric patients. Some cases resulted in heat stroke that required hospital treatment and resulted in death.(1) |
ZONEGRAN, ZONISADE, ZONISAMIDE |
| Topiramate/Anticholinergics SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Topiramate can cause decreased sweating and elevated body temperature. Agents with anticholinergic activity can predispose patients to heat-related disorders.(1-2) CLINICAL EFFECTS: Concurrent use of topiramate with agents with anticholinergic activity may increase the incidence of oligohidrosis and hyperthermia, especially in pediatric or adolescent patients.(1-2) Overheating and dehydration can lead to brain damage and death. PREDISPOSING FACTORS: Pediatric and adolescent patients and patients with dehydration may be more likely to experience heat-related disorders.(1) PATIENT MANAGEMENT: The manufacturer of topiramate states that caution should be used when topiramate is prescribed with other medicinal products that predispose to heat-related disorders, such as agents with anticholinergic activity (e.g. clomipramine, hydroxyzine, diphenhydramine, haloperidol, imipramine, and oxybutynin) concurrently with zonisamide.(1) Monitor for signs and symptoms of heat stroke: skin feels very hot with little or no sweating, confusion, muscle cramps, rapid heartbeat, or rapid breathing. Monitor for signs and symptoms of dehydration: dry mouth, urinating less than usual, dark-colored urine, dry skin, feeling tired, dizziness, or irritability. If signs or symptoms of dehydration, oligohidrosis, or elevated body temperature occur, discontinuation of zonisamide should be considered. DISCUSSION: Case reports of decreased sweating and elevated temperature have been reported, especially in pediatric patients. Some cases resulted in heat stroke that required hospital treatment.(1) A 64-year old woman developed non-exertional hyperthemia while taking multiple psychiatric medications with topiramate.(2) |
EPRONTIA, PHENTERMINE-TOPIRAMATE ER, QSYMIA, TOPAMAX, TOPIRAMATE, TOPIRAMATE ER, TOPIRAMATE ER SPRINKLE, TROKENDI XR |
| Dextromethorphan/Selected Serotonergic Agents SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Dextromethorphan inhibits neuronal reuptake of serotonin. Concurrent administration with one or more serotonergic agents may increase serotonin effects, leading to serotonin toxicity.(1-11) CLINICAL EFFECTS: The concurrent use of dextromethorphan with serotonergic agents may increase the risk for serotonin syndrome. Serotonin syndrome constitutes a range of toxicities from mild to life threatening.(3) Mild serotonin symptoms may include: shivering, diaphoresis, mydriasis, intermittent tremor, and/or myoclonus.(3) Moderate serotonin symptoms may include: tachycardia, hypertension, hyperthermia, mydriasis, diaphoresis, hyperactive bowel sounds, hyperreflexia, and/OR clonus.(3) Severe serotonin symptoms may include: severe hypertension and tachycardia, shock, agitated delirium, muscular rigidity, and/or hypertonicity.(3) PREDISPOSING FACTORS: Concurrent use of additional drugs which increase CNS serotonin levels would be expected to further increase risk for serotonin syndrome.(1-11) PATIENT MANAGEMENT: Monitor patients on multiple serotonergic agents for symptoms of serotonin toxicity. Patients in whom serotonin syndrome is suspected should receive immediate medical attention. If the interacting agents are prescribed by different providers, it would be prudent to assure that both are aware of concomitant therapy and monitoring the patient for serotonin toxicities. Advise patients not to exceed recommended dosages of dextromethorphan. If concurrent therapy is warranted, patients should be monitored for signs and symptoms of serotonin syndrome. Instruct patients to report muscle twitching, tremors, shivering and stiffness, fever, heavy sweating, heart palpitations, restlessness, confusion, agitation, trouble with coordination, or severe diarrhea. DISCUSSION: Dextromethorphan inhibits neuronal reuptake of serotonin and may potentially precipitate dose-dependant serotonin toxicity in conjunction with other serotonergic agents.(4,5) Serotonin syndrome has been reported in patients following the addition of dextromethorphan containing cough syrups to duloxetine,(6) escitalopram,(7) fluoxetine,(8,9) paroxetine,(10) and sertraline.(11) Selected serotonergic agents linked to this monograph include: citalopram, clomipramine, duloxetine, escitalopram, fluvoxamine, imipramine, levomilnacipran, milnacipran, sertraline, venlafaxine, vilazodone and vortioxetine. |
ANAFRANIL, CELEXA, CITALOPRAM HBR, CLOMIPRAMINE HCL, DRIZALMA SPRINKLE, DULOXETINE HCL, DULOXICAINE, EFFEXOR XR, ESCITALOPRAM OXALATE, FETZIMA, FLUVOXAMINE MALEATE, FLUVOXAMINE MALEATE ER, IMIPRAMINE HCL, IMIPRAMINE PAMOATE, LEXAPRO, SAVELLA, SERTRALINE HCL, TRINTELLIX, VENLAFAXINE BESYLATE ER, VENLAFAXINE HCL, VENLAFAXINE HCL ER, VIIBRYD, VILAZODONE HCL, ZOLOFT |
| Dextromethorphan/Selected Strong CYP2D6 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Strong inhibitors of CYP2D6 may inhibit the metabolism of dextromethorphan.(1-4) CLINICAL EFFECTS: Patients may experience increased adverse effects of dextromethorphan due to elevated systemic concentrations. Elevated levels of dextromethorphan or concomitant use of two or more serotonergic agents increases the risk for serotonin syndrome. Serotonin syndrome constitutes a range of toxicities from mild to life threatening.(5) Mild serotonin symptoms may include: shivering, diaphoresis, mydriasis, intermittent tremor, and/or myoclonus.(5) Moderate serotonin symptoms may include: tachycardia, hypertension, hyperthermia, mydriasis, diaphoresis, hyperactive bowel sounds, hyperreflexia, and/OR clonus.(5) Severe serotonin symptoms may include: severe hypertension and tachycardia, shock, agitated delirium, muscular rigidity, and/or hypertonicity.(5) PREDISPOSING FACTORS: Concurrent use of additional drugs which increase CNS serotonin levels would be expected to further increase risk for serotonin syndrome.(5) PATIENT MANAGEMENT: Monitor patients for elevated dextromethorphan levels or on multiple serotonergic agents for symptoms of serotonin toxicity. Patients in whom serotonin syndrome is suspected should receive immediate medical attention. If the interacting agents are prescribed by different providers, it would be prudent to assure that both are aware of concomitant therapy and monitoring the patient for serotonin toxicities. Advise patients not to exceed recommended dosages of dextromethorphan. If concurrent therapy is warranted, patients should be monitored for signs and symptoms of serotonin syndrome. Instruct patients to report muscle twitching, tremors, shivering and stiffness, fever, heavy sweating, heart palpitations, restlessness, confusion, agitation, trouble with coordination, or severe diarrhea. DISCUSSION: An open label parallel group trial evaluated the interaction between dextromethorphan-quinidine 30 mg-30 mg (higher than marketed strength of 20 mg-10 mg) and paroxetine 20 mg in 27 healthy volunteers with a mean age of 33.6 years. Subjects were randomly divided into 2 groups: - Group 1 received paroxetine 20 mg once daily for 12 days, followed by the addition of dextromethorphan-quinidine twice daily for 8 days. - Group 2 received dextromethorphan-quinidine twice daily for 8 days, followed by paroxetine 20 mg daily for 12 days. Results: overall, adverse effects were reported in 19 of 26 subjects who received combination therapy (73%) and 15 of 27 subjects who received monotherapy (56%). Adverse effects from the combination differed somewhat between groups and were more closely associated with the second drug product administered. Group 1 reported dizziness, headache, somnolence, euphoria, nausea, and vomiting after the addition of dextromethorphan-quinidine to paroxetine. Group 2 adverse events were dizziness, headache, nausea, vomiting, insomnia, anxiety, and hyperhidrosis after the addition of paroxetine to dextromethorphan.(1) Two weeks of fluoxetine therapy increased the area-under-curve (AUC) of dextromethorphan by 27-fold.(4) Serotonin syndrome has been reported in patients following the addition of dextromethorphan containing cough syrups to fluoxetine(6,7) and paroxetine.(8) Selected strong CYP2D6 inhibitors linked to this monograph include: bupropion, dacomitinib, hydroquinidine, quinidine, and terbinafine.(8) |
APLENZIN, AUVELITY, BUPROPION HCL, BUPROPION HCL SR, BUPROPION XL, CONTRAVE, FORFIVO XL, NUEDEXTA, QUINIDINE GLUCONATE, QUINIDINE SULFATE, TERBINAFINE HCL, VIZIMPRO, WELLBUTRIN SR, WELLBUTRIN XL |
| Propranolol/Selected CYP2D6 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: CYP2D6 inhibitors may inhibit the metabolism of propranolol.(1) CLINICAL EFFECTS: Concurrent use of CYP2D6 inhibitors may result in elevated levels of and toxicity from propranolol, including hypotension and bradycardia.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Monitor patients receiving concurrent therapy with propranolol and CYP2D6 inhibitors. The dosage of propranolol may need to be adjusted.(1) DISCUSSION: In a pharmacokinetic study in 16 healthy volunteers, concurrent use of quinidine 200 mg (a CYP2D6 inhibitor) increased the area-under-curve (AUC) of propranolol by 2.29-fold.(2) In a pharmacokinetic study in 6 healthy subjects, concurrent use of quinidine increased propranolol AUC 2-fold.(3) A retrospective review of concurrent use of propranolol and antidepressants evaluated the risk of hospitalization or emergency room visit within 30 days of concurrent prescription. In patients receiving antidepressants with moderate to strong CYP2D6 inhibitory effects, patient were an increased risk compared to patients receiving no antidepressants (Hazard Ratio (HR) = 1.53; 95% CI 1.03-2.81 vs. HR = 1.24; 95% CI 0.82-1.88).(4) Case reports of bradycardia and cardiac adverse effects have been reported with concurrent use of propranolol and the antidepressants fluoxetine and paroxetine (strong CYP2D6 inhibitors).(5) Strong CYP2D6 inhibitors include: bupropion, dacomitinib, fluoxetine, mavorixafor, and paroxetine. Moderate CYP2D6 inhibitors include: abiraterone, asunaprevir, berotralstat, capivasertib, cinacalcet, duloxetine, eliglustat, escitalopram, lorcaserin, mirabegron, moclobemide, quinine, ranolazine, and rolapitant. Weak CYP2D6 inhibitors include: celecoxib, desvenlafaxine, diphenhydramine, dimenhydrinate, dronabinol, fedratinib, hydroxychloroquine, imatinib, osilodrostat, ranitidine, and sertraline.(6) |
HEMANGEOL, INDERAL LA, INDERAL XL, INNOPRAN XL, PROPRANOLOL HCL, PROPRANOLOL HCL ER, PROPRANOLOL-HYDROCHLOROTHIAZID |
| Ziprasidone/Serotonergic Agents SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Ziprasidone is a 5-HT1A agonist and serotonin and norepinephrine reuptake inhibitor. Concurrent administration with one or more serotonergic agents may increase serotonin effects, resulting in serotonin toxicity.(1,2) CLINICAL EFFECTS: Concurrent use of ziprasidone and other serotonergic agents may result in serotonin syndrome, a potentially life-threatening condition with symptoms including altered mental status, hypertension, restlessness, myoclonus, hyperthermia, hyperreflexia, diaphoresis, shivering, and tremor.(1) PREDISPOSING FACTORS: Serotonin syndrome risk is dose-related. Higher systemic concentrations of either drug would be predicted to increase risk for serotonin toxicity.(2) Concomitant therapy with multiple agents which increase brain serotonin concentrations may also increase risk for serotonin syndrome.(2) PATIENT MANAGEMENT: Caution patients about the risk of serotonin syndrome with the concomitant use of ziprasidone with other serotonergic drugs. Instruct patients to contact their healthcare provider, or report to the emergency room, should they experience signs or symptoms of serotonin syndrome.(1) DISCUSSION: Several cases of serotonin syndrome have been reported in patients receiving ziprasidone.(4-6) |
GEODON, ZIPRASIDONE HCL, ZIPRASIDONE MESYLATE |
The following contraindication information is available for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan):
Drug contraindication overview.
*Known hypersensitivity to phenylephrine or to any ingredient in the respective formulation.
*Known hypersensitivity to phenylephrine or to any ingredient in the respective formulation.
There are 1 contraindications.
Absolute contraindication.
| Contraindication List |
|---|
| Severe uncontrolled hypertension |
There are 10 severe contraindications.
Adequate patient monitoring is recommended for safer drug use.
| Severe List |
|---|
| Angle-closure glaucoma |
| Benign prostatic hyperplasia |
| Bladder outflow obstruction |
| Chronic idiopathic constipation |
| Coronary artery disease |
| Hypertension |
| Hyperthyroidism |
| Stenosing peptic ulcer |
| Systemic mastocytosis |
| Urinary retention |
There are 7 moderate contraindications.
Clinically significant contraindication, where the condition can be managed or treated before the drug may be given safely.
| Moderate List |
|---|
| Chronic heart failure |
| Coronary artery disease |
| Hypertension |
| Hyperthyroidism |
| Ocular hypertension |
| Pyloroduodenal obstruction |
| Seizure disorder |
The following adverse reaction information is available for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan):
Adverse reaction overview.
The most commonly reported adverse effects in patients receiving IV phenylephrine hydrochloride were nausea, vomiting, and headache.
The most commonly reported adverse effects in patients receiving IV phenylephrine hydrochloride were nausea, vomiting, and headache.
There are 18 severe adverse reactions.
| More Frequent | Less Frequent |
|---|---|
| None. | None. |
| Rare/Very Rare |
|---|
|
Anaphylaxis Blood dyscrasias Cardiac arrhythmia Dizziness Extrasystoles Hallucinations Headache disorder Hemolytic anemia Hyperhidrosis Hypersensitivity drug reaction Hypotension Insomnia Nervousness Pallor Seizure disorder Tachycardia Tremor Vomiting |
There are 56 less severe adverse reactions.
| More Frequent | Less Frequent |
|---|---|
|
Anticholinergic toxicity Dizziness Drowsy Thick bronchial secretions |
Muscle weakness Sedation |
| Rare/Very Rare |
|---|
|
Abdominal distension Abdominal pain with cramps Accidental fall Acute abdominal pain Acute cognitive impairment Agitation Anorexia Anticholinergic toxicity Ataxia Blurred vision Chest discomfort Chills Constipation Diarrhea Diplopia Dizziness Drowsy Dry nose Dry throat Dyspnea Dysuria Euphoria Excitement Fatigue Headache disorder Hyperhidrosis Insomnia Irritability Maculopapular rash Malaise Migraine Nausea Nervousness Nightmares Palpitations Paresthesia Pruritus of skin Skin photosensitivity Skin rash Symptoms of anxiety Tachycardia Tinnitus Tremor Urinary retention Urticaria Vertigo Visual changes Vomiting Wheezing Xerostomia |
The following precautions are available for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan):
The manufacturers state that safety and efficacy of parenteral preparations of phenylephrine hydrochloride have not been established in pediatric patients.
Contraindicated
Severe Precaution
Management or Monitoring Precaution
Contraindicated
| None |
Severe Precaution
| None |
Management or Monitoring Precaution
| None |
There is inadequate experience with use of brompheniramine or dexbrompheniramine in pregnant women to determine whether the potential for harm to the fetus exists. Because of the risk of severe reactions (e.g., seizures) to antihistamines in neonates, brompheniramine or dexbrompheniramine should not be used during the third trimester; the drugs should be used during the first 2 trimesters only when the potential benefits justify the possible risks to the fetus. Reproduction studies in rats and rabbits receiving diphenhydramine hydrochloride dosages up to 5 times the recommended human dosage have not revealed evidence of harm to the fetus.
However, diphenhydramine has been shown to cross the placenta. In one epidemiologic study, use of bromodiphenhydramine (no longer commercially available) but not diphenhydramine was associated with an increased risk of teratogenic effects. In another epidemiologic study, there also was no evidence of increased risk of teratogenicity associated with diphenhydramine use during the first trimester, although a modest association could not be ruled out.
Use of diphenhydramine during the first trimester of pregnancy has been associated with an increased risk of cleft palate alone or combined with other fetal abnormalities, and the drug has been reported to potentiate the teratogenic effect of morphine in mice. The manufacturers state that there are no adequate and controlled studies to date using diphenhydramine in pregnant women, and the drugs should be used during pregnancy only when clearly needed. Data from randomized trials and meta-analyses with phenylephrine injection in pregnant women undergoing Cesarean section have not established a drug-associated risk of major birth defects or miscarriage.
Additionally, the data did not identify adverse effects on maternal outcomes or infant Apgar scores. At recommended doses, phenylephrine does not appear to significantly affect fetal heart rate or fetal heart rate variability. Data are not available on phenylephrine use during the first or second trimester.
Untreated hypotension in pregnant women undergoing Cesarean delivery with neuraxial anesthesia has been associated with increased maternal nausea and vomiting. A sustained decrease in uterine blood flow caused by maternal hypotension has also been associated with fetal bradycardia and acidosis. No data are available on the safety of phenylephrine injection during the period of organogenesis; therefore, conclusions cannot be drawn regarding the risk of birth defects from drug exposure.
In addition, no data are available on the risk of miscarriage following fetal exposure to phenylephrine injection. In animal studies, fetal malformations were observed following phenylephrine infusion over 1 hour during the period of organogenesis at a dosage of 1.2 times the human daily dosage.
Decreased pup weight was also observed in offspring of pregnant rats who received 2.9 times the human daily dose of phenylephrine. If a vasopressor is used in conjunction with oxytocic drugs, the vasopressor effect is potentiated and may result in serious adverse effects.
However, diphenhydramine has been shown to cross the placenta. In one epidemiologic study, use of bromodiphenhydramine (no longer commercially available) but not diphenhydramine was associated with an increased risk of teratogenic effects. In another epidemiologic study, there also was no evidence of increased risk of teratogenicity associated with diphenhydramine use during the first trimester, although a modest association could not be ruled out.
Use of diphenhydramine during the first trimester of pregnancy has been associated with an increased risk of cleft palate alone or combined with other fetal abnormalities, and the drug has been reported to potentiate the teratogenic effect of morphine in mice. The manufacturers state that there are no adequate and controlled studies to date using diphenhydramine in pregnant women, and the drugs should be used during pregnancy only when clearly needed. Data from randomized trials and meta-analyses with phenylephrine injection in pregnant women undergoing Cesarean section have not established a drug-associated risk of major birth defects or miscarriage.
Additionally, the data did not identify adverse effects on maternal outcomes or infant Apgar scores. At recommended doses, phenylephrine does not appear to significantly affect fetal heart rate or fetal heart rate variability. Data are not available on phenylephrine use during the first or second trimester.
Untreated hypotension in pregnant women undergoing Cesarean delivery with neuraxial anesthesia has been associated with increased maternal nausea and vomiting. A sustained decrease in uterine blood flow caused by maternal hypotension has also been associated with fetal bradycardia and acidosis. No data are available on the safety of phenylephrine injection during the period of organogenesis; therefore, conclusions cannot be drawn regarding the risk of birth defects from drug exposure.
In addition, no data are available on the risk of miscarriage following fetal exposure to phenylephrine injection. In animal studies, fetal malformations were observed following phenylephrine infusion over 1 hour during the period of organogenesis at a dosage of 1.2 times the human daily dosage.
Decreased pup weight was also observed in offspring of pregnant rats who received 2.9 times the human daily dose of phenylephrine. If a vasopressor is used in conjunction with oxytocic drugs, the vasopressor effect is potentiated and may result in serious adverse effects.
It is not known if brompheniramine is distributed into milk. Because of the potential for serious adverse reactions to antihistamines in nursing infants, a decision should be made whether to discontinue nursing or brompheniramine or dexbrompheniramine, taking into account the importance of the drug to the woman. Excessive crying, irritability, and sleep disturbances occurred in one breast-fed infant whose mother was receiving dexbrompheniramine combined with pseudoephedrine; normal behavior in the infant resumed within 12 hours after the mother discontinued the drug and the infant received 2 formula feedings.
Diphenhydramine has been detected in milk. Because of the potential for serious adverse reactions to antihistamines in nursing infants, a decision should be made whether to discontinue nursing or diphenhydramine, taking into account the importance of the drug to the woman. There are no data on whether phenylephrine or its metabolite is distributed into human or animal milk following parenteral administration.
The effects on the breast-fed infant and milk production are not known. The developmental and health benefits of breast-feeding should be weighed along with the mother's clinical need for the drug and any potential adverse effects on the breast-fed infant from phenylephrine or from the underlying maternal condition.
Diphenhydramine has been detected in milk. Because of the potential for serious adverse reactions to antihistamines in nursing infants, a decision should be made whether to discontinue nursing or diphenhydramine, taking into account the importance of the drug to the woman. There are no data on whether phenylephrine or its metabolite is distributed into human or animal milk following parenteral administration.
The effects on the breast-fed infant and milk production are not known. The developmental and health benefits of breast-feeding should be weighed along with the mother's clinical need for the drug and any potential adverse effects on the breast-fed infant from phenylephrine or from the underlying maternal condition.
Clinical studies of phenylephrine hydrochloride did not include sufficient numbers of patients >=65 years of age to determine whether geriatric patients respond differently than younger patients. Clinical experience to date has not identified any differences in response between geriatric and younger patients. If phenylephrine is used in geriatric patients, dosage should be selected carefully, usually starting at the low end of the dosage range, since renal, hepatic, and cardiovascular dysfunction and concomitant disease or other drug therapy are more common in this age group.
The following prioritized warning is available for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan):
No warning message for this drug.
No warning message for this drug.
The following icd codes are available for CHILDREN'S DIMETAPP DAY NIGHT (diphenhydramine/brompheniramine/phenyleph/dextromethorphan)'s list of indications:
| Allergic rhinitis | |
| J30.1 | Allergic rhinitis due to pollen |
| J30.2 | Other seasonal allergic rhinitis |
| J30.5 | Allergic rhinitis due to food |
| J30.8 | Other allergic rhinitis |
| J30.81 | Allergic rhinitis due to animal (cat) (dog) hair and dander |
| J30.89 | Other allergic rhinitis |
| J30.9 | Allergic rhinitis, unspecified |
| Cold symptoms | |
| J00 | Acute nasopharyngitis [common cold] |
| Cough | |
| R05 | Cough |
| R05.1 | Acute cough |
| R05.2 | Subacute cough |
| R05.3 | Chronic cough |
| R05.9 | Cough, unspecified |
| Nasal congestion | |
| R09.81 | Nasal congestion |
| Rhinorrhea | |
| R09.82 | Postnasal drip |
| Vasomotor rhinitis | |
| J30.0 | Vasomotor rhinitis |
Formulary Reference Tool