Please wait while the formulary information is being retrieved.
Drug overview for NORVASC (amlodipine besylate):
Generic name: amlodipine besylate (am-LOE-di-peen)
Drug class: Calcium Channel Blockers
Therapeutic class: Cardiovascular Therapy Agents
Amlodipine is a 1,4-dihydropyridine-derivative calcium-channel blocking agent with an intrinsically long duration of action.
No enhanced Uses information available for this drug.
Generic name: amlodipine besylate (am-LOE-di-peen)
Drug class: Calcium Channel Blockers
Therapeutic class: Cardiovascular Therapy Agents
Amlodipine is a 1,4-dihydropyridine-derivative calcium-channel blocking agent with an intrinsically long duration of action.
No enhanced Uses information available for this drug.
DRUG IMAGES
AMLODIPINE BESYLATE 2.5 MG TAB
AMLODIPINE BESYLATE 5 MG TAB
AMLODIPINE BESYLATE 10 MG TAB
The following indications for NORVASC (amlodipine besylate) have been approved by the FDA:
Indications:
Hypertension
Prevention of anginal pain associated with coronary artery disease
Prevention of anginal pain associated with vasospastic angina
Professional Synonyms:
Elevated blood pressure
Essential hypertension
Hyperpiesia
Hyperpiesis
Hypertensive disorder
Prevention of anginal pain associated with angina inversa
Prevention of anginal pain associated with CAD
Prevention of anginal pain associated with Prinzmetal angina
Prevention of anginal pain associated with variant angina
Systemic arterial hypertension
Indications:
Hypertension
Prevention of anginal pain associated with coronary artery disease
Prevention of anginal pain associated with vasospastic angina
Professional Synonyms:
Elevated blood pressure
Essential hypertension
Hyperpiesia
Hyperpiesis
Hypertensive disorder
Prevention of anginal pain associated with angina inversa
Prevention of anginal pain associated with CAD
Prevention of anginal pain associated with Prinzmetal angina
Prevention of anginal pain associated with variant angina
Systemic arterial hypertension
The following dosing information is available for NORVASC (amlodipine besylate):
Dosage of amlodipine besylate is expressed in terms of amlodipine.
Amlodipine besylate is administered orally. Amlodipine generally can be given without regard to meals.
| DRUG LABEL | DOSING TYPE | DOSING INSTRUCTIONS |
|---|---|---|
| NORVASC 2.5 MG TABLET | Maintenance | Adults take 1 tablet (2.5 mg) by oral route once daily |
| NORVASC 5 MG TABLET | Maintenance | Adults take 1 tablet (5 mg) by oral route once daily |
| NORVASC 10 MG TABLET | Maintenance | Adults take 1 tablet (10 mg) by oral route once daily |
| DRUG LABEL | DOSING TYPE | DOSING INSTRUCTIONS |
|---|---|---|
| AMLODIPINE BESYLATE 2.5 MG TAB | Maintenance | Adults take 1 tablet (2.5 mg) by oral route once daily |
| AMLODIPINE BESYLATE 5 MG TAB | Maintenance | Adults take 1 tablet (5 mg) by oral route once daily |
| AMLODIPINE BESYLATE 10 MG TAB | Maintenance | Adults take 1 tablet (10 mg) by oral route once daily |
The following drug interaction information is available for NORVASC (amlodipine besylate):
There are 2 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 |
|---|---|
| Simvastatin (Greater Than 20 mg)/Amlodipine 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: Amlodipine may inhibit the metabolism of simvastatin by CYP3A4.(1-7) Levamlodipine is the active isomer of amlodipine.(8) CLINICAL EFFECTS: Concurrent amlodipine may result in elevated levels of simvastatin,(1-7) which may result in myopathy and rhabdomyolysis. PREDISPOSING FACTORS: The risk for myopathy or rhabdomyolysis may be greater in patients 65 years and older, inadequately treated hypothyroidism, renal impairment, carnitine deficiency, malignant hyperthermia, or in patients with a history of myopathy or rhabdomyolysis. Patients with a SLCO1B1 polymorphism that leads to decreased function of the hepatic uptake transporter OATP1B1 may have increased statin concentrations and be predisposed to myopathy or rhabdomyolysis. PATIENT MANAGEMENT: Do not exceed a dosage of 20 mg daily of simvastatin in patients receiving concurrent therapy with amlodipine.(1-4) Consider separating the administration times of amlodipine and simvastatin in patients receiving concurrent therapy with amlodipine and simvastatin doses of 20 mg or less.(5) If concurrent therapy is deemed medically necessary, monitor patients for signs and symptoms of myopathy/rhabdomyolysis, including muscle pain/tenderness/weakness, fever, unusual tiredness, changes in the amount of urine, and/or discolored urine. DISCUSSION: In a study in 8 patients with hypercholesterolemia and hypertension, 4 weeks of concurrent administration of amlodipine (5 mg daily) increased the maximum concentration (Cmax) and area-under-curve (AUC) of simvastatin (5 mg daily) by 43% and 28%, respectively. There were no changes in the lipid-lowering affects of simvastatin.(6) In a study in 17 subjects, administration of amlodipine (5 mg daily) 4 hours after simvastatin (5 mg daily) resulted in Cmax and AUC values of simvastatin that were 63.2% and 66.0%, respectively, of values obtained with simultaneous dosing.(5) Acute renal failure and rhabdomyolysis was reported in patient maintained on amlodipine and alprazolam two days after beginning the maximal dose of simvastatin.(7) |
EZETIMIBE-SIMVASTATIN, FLOLIPID, SIMVASTATIN, VYTORIN, ZOCOR |
| Lemborexant (Greater Than 5 mg)/Weak CYP3A4 Inhibitors 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: Inhibitors of CYP3A4 may inhibit the metabolism of lemborexant.(1) CLINICAL EFFECTS: Concurrent use of an inhibitor of CYP3A4 may result in increased levels of and effects from lemborexant, including somnolence, fatigue, CNS depressant effects, daytime impairment, headache, and nightmare or abnormal dreams.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The maximum recommended dose of lemborexant with concurrent use of a weak CYP3A4 inhibitors should not exceed 5 mg per dose.(1) DISCUSSION: Lemborexant is a CYP3A4 substrate. In a PKPB model, concurrent use of lemborexant with itraconazole increased area-under-curve (AUC) and concentration maximum (Cmax) by 3.75-fold and 1.5-fold, respectively. Concurrent use of lemborexant with fluconazole increased AUC and Cmax by 4.25-fold and 1.75-fold, respectively.(1) Weak inhibitors of CYP3A4 include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, capivasertib, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, daridorexant, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, mavorixafor, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan.(1,2) |
DAYVIGO |
There are 5 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 |
|---|---|
| Selected Calcium Channel Blockers/Rifamycins SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Multiple mechanisms appear to be involved. Rifampin may increase the hepatic metabolism of the calcium channel blockers, increase first-pass hepatic metabolism of oral calcium channel blockers, and decrease the protein binding of calcium channel blockers.(1-8) CLINICAL EFFECTS: Concurrent use of rifampin may decrease levels and effectiveness of the calcium channel blocker.(1-8) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Observe the patient for a decrease in the therapeutic effects of the calcium channel blocker if rifampin is initiated. The dose of the calcium channel blocker may need to be adjusted if rifampin is initiated or discontinued.(1-7) The US manufacturer of diltiazem states that concurrent use should be avoided.(2) The manufacturer of lercanidipine states that concurrent use is not recommended.(10) DISCUSSION: In healthy subjects, pretreatment with rifampin (600 mg daily) reduced the concentration of a single dose of isradipine (5 mg) below a detectable level. The study concluded that the concentrations and effects of isradipine may be either reduced or absent as a result of increased isradipine metabolism.(1) Concurrent administration of rifampin has been shown to lower diltiazem levels below detectable limits.(2) In a study in 5 healthy subjects, pretreatment with rifampin (6 days) decreased the area-under-curve (AUC) of a single oral dose of nilvadipine (4 mg) by 96.5%. Pretreatment with rifampin abolished nilvadipine-induced hypotensive effects and tachycardia.(3) A study in six subjects examined the effects of pretreatment with rifampin (600 mg daily for 15 days) on single doses of verapamil (10 mg intravenously or 120 mg orally). Rifampin significantly decreased the maximum concentration (Cmax) and AUC of oral verapamil and resulted in no changes in the P-R interval. There were small decreases in the AUC of intravenous verapamil.(4) In a study in 8 male subjects, pretreatment with rifampin (600 mg daily for 15 days) increased the systemic clearance of S-verapamil by 1.3-fold and the apparent oral-clearance of S-verapamil by 32-fold. The bioavailability of S-verapamil decreased 25-fold. The effect of oral verapamil on AV conduction was almost abolished. No significant changes were noted for intravenous administration of verapamil.(5) In a study in 16 hypertensive chronic kidney disease patients, amlodipine levels decreased an average of 82% after initiation of rifampin. In eight of the 16 patients, the levels were undetectable.(9) There have been case reports of decreased effectiveness of barnidipine,(6) manidipine,(6) nisoldipine,(6) and verapamil(7,8) during concurrent rifampin therapy. |
PRIFTIN, RIFABUTIN, RIFADIN, RIFAMPIN, TALICIA |
| Amlodipine; Levamlodipine/Conivaptan SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Conivaptan may inhibit the metabolism of amlodipine via CYP3A4.(1) Levamlodipine is the active isomer of amlodipine.(2) CLINICAL EFFECTS: Concurrent use of amlodipine or levamlodipine and conivaptan may result in increased levels of amlodipine or levamlodipine, which may lead to increased clinical effects and toxicity.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US manufacturer of conivaptan states that concurrent use of agents primarily metabolized by CYP3A4, such as amlodipine or levamlodipine, should be avoided. Amlodipine or levamlodipine may be initiated no sooner than 1 week after the infusion of conivaptan is completed.(1) DISCUSSION: Conivaptan is a potent inhibitor of CYP3A4. In an evaluation of the combination of oral conivaptan (80 mg/day) and amlodipine, the area-under-curve (AUC) and half life of amlodipine were both increased 2-fold.(1) |
CONIVAPTAN-D5W, VAPRISOL-5% DEXTROSE |
| Dantrolene/Calcium Channel Blockers SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: The exact mechanism is unknown. Dantrolene may decrease the release of calcium from the sarcoplasmic reticulum, resulting in additive or synergistic effects with calcium channel blockers.(1) CLINICAL EFFECTS: Concurrent use of dantrolene and calcium channel blockers may result in cardiogenic shock.(2-4) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US, UK, and Australian manufacturers of dantrolene state that concurrent use with calcium channel blockers during the management of malignant hyperthermia crisis is not recommended.(2-4) The Australian and UK manufacturers of diltiazem state that concurrent use of dantrolene infusion with calcium channel blockers is contraindicated.(5-6) DISCUSSION: Cardiogenic shock in patients treated simultaneously with verapamil and dantrolene is rare but has been reported.(2-4,7) Concurrent use of dantrolene and verapamil in swine has been reported to result in cardiogenic shock and hyperkalemia.(8) In dogs, the combination has been reported to cause hyperkalemia.(9) The combination of diltiazem and dantrolene has been reported to cause adverse cardiovascular effects in swine.(10) A study in swine showed no adverse effects from the combination of dantrolene and nifedipine(10) and one patient who experience cardiogenic shock with dantrolene and verapamil had no adverse effects with the combination of dantrolene and nifedipine;(7) however, the US manufacturer cannot endorse the safety of the combination.(2) |
DANTRIUM, DANTROLENE SODIUM, REVONTO, RYANODEX |
| Lomitapide (Less Than or Equal To 30 mg)/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Weak inhibitors of CYP3A4 may inhibit the metabolism of lomitapide.(1) Lomitapide is very susceptible to CYP3A4 inhibition. For example, in an interaction study with a strong CYP3A4 inhibitor (ketoconazole) lomitapide exposure was increased 27-fold.(2) Thus even weak CYP3A4 inhibitors may affect lomitapide exposure (AUC, area-under-curve). CLINICAL EFFECTS: Concurrent use of a weak inhibitor of CYP3A4 may result in 2-fold increases in lomitapide levels and toxicity from lomitapide.(1) PREDISPOSING FACTORS: This interaction may be more severe in patients with hepatic impairment or with end-stage renal disease.(1) PATIENT MANAGEMENT: The maximum lomitapide dose should be 30 mg daily for patients taking concomitant weak CYP3A4 inhibitors. Due to lomitapide's long half-life, it may take 1 to 2 weeks to see the full effect of this interaction. When initiating a weak CYP3A4 inhibitor in patients taking lomitapide 10 mg daily or more, decrease the dose of lomitapide by 50%. In patients taking lomitapide 5 mg daily, continue current dose. DISCUSSION: Lomitapide is very susceptible to CYP3A4 inhibition. For example, in an interaction study with a strong CYP3A4 inhibitor (ketoconazole) lomitapide exposure was increased 27-fold.(2) Based upon interactions with stronger inhibitors, weak inhibitors of CYP3A4 are predicted to increase lomitapide area-under-curve(AUC) 2-fold.(1) Weak CYP3A4 inhibitors linked to this interaction include alprazolam, amiodarone, amlodipine, asciminib, atorvastatin, azithromycin, Baikal skullcap, belumosudil, bicalutamide, blueberry juice, brodalumab, cannabidiol, capivasertib, cilostazol, cimetidine, ciprofloxacin, chlorzoxazone, clotrimazole, cranberry juice, cyclosporine, daridorexant, delavirdine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, larotrectinib, lacidipine, lapatinib, lazertinib, leflunomide, levamlodipine, linagliptin, lurasidone, maribavir, mavorixafor, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, sitaxsentan, skullcap, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, vonoprazan, and zileuton.(1-3) |
JUXTAPID |
| Eliglustat/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Weak inhibitors of CYP3A4 may inhibit the metabolism of eliglustat. If the patient is also taking an inhibitor of CYP2D6, eliglustat metabolism can be further inhibited.(1) CLINICAL EFFECTS: Concurrent use of an agent that is a weak inhibitor of CYP3A4 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 CYP2D6, is a poor metabolizer of CYP2D6, 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 concurrent use of eliglustat with weak inhibitors of CYP3A4 in poor metabolizers of CYP2D6 should be avoided.(1) The dosage of eliglustat with weak inhibitors of CYP3A4 in extensive metabolizers of CYP2D6 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: Ketoconazole (400 mg daily), a strong inhibitor of CYP3A4, increased eliglustat (84 mg BID) maximum concentration (Cmax) and area-under-curve (AUC) by 4-fold and 4.4-fold, respectively, in extensive metabolizers. Physiologically-based pharmacokinetic (PKPB) models suggested ketoconazole would increase eliglustat Cmax and AUC by 4.4-fold and 5.4-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 fluconazole, a moderate inhibitor of CYP3A4, would increase eliglustat Cmax and AUC by 2.8-fold and 3.2-fold, respectively, in extensive metabolizers and by 2.5-fold and 2.9-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) Weak inhibitors of CYP3A4 include: alprazolam, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, daridorexant, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, and vonoprazan.(3,4) |
CERDELGA |
There are 15 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 |
|---|---|
| Cyclosporine/Calcium Channel Blockers SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Calcium channel blockers may inhibit the metabolism of cyclosporine by CYP3A4. CLINICAL EFFECTS: Concurrent use of calcium channel blockers may result in elevated levels of and toxicity from cyclosporine. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Monitor cyclosporine levels when initiating or discontinuing calcium channel blockers. DISCUSSION: Concurrent administration of cyclosporine and amlodipine, diltiazem, nicardipine, or verapamil has caused elevated cyclosporine levels. Renal toxicity was seen in some cases. Upon discontinuation of the calcium channel blocker, cyclosporine concentrations have returned to baseline levels. With concurrent diltiazem administration, cyclosporine dosage decreases of 15% to 48% were required. A prospective study in 11 renal transplant patients showed a 40% increase in trough cyclosporine levels when given concomitantly with amlodipine.(29) |
CYCLOSPORINE, CYCLOSPORINE MODIFIED, GENGRAF, NEORAL, SANDIMMUNE |
| Slt Calcium Channel Blockers/Atazanavir;Darunavir;Fosamprenavir SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Atazanavir, darunavir, and fosamprenavir may inhibit the CYP3A4-mediated metabolism of calcium channel blockers.(1-5) CLINICAL EFFECTS: Concurrent use of atazanavir, darunavir, or fosamprenavir may result in increased levels of calcium channel blockers. The combination of atazanavir with non-dihydropyridines may result in an additive effect on the PR interval.(1-2,6-7) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US Department of Health and Human Services HIV guidelines recommend that concurrent use of calcium channel blockers with protease inhibitors be monitored closely. The dose of the calcium channel blocker should be titrated to clinical response and adverse events.(5) Additional recommendations apply to patients on atazanavir. EKG monitoring is recommended for patients on concurrent therapy with calcium channel blockers. A dose reduction of diltiazem by 50% should be considered for patients starting atazanavir.(1,2,5) DISCUSSION: In a study in 28 subjects, concurrent atazanavir (400 mg daily) with diltiazem (180 mg daily) increased the diltiazem area-under-curve (AUC) and maximum concentration (Cmax) by 225% and 98%, respectively.(1,2) Diltiazem minimum concentration (Cmin) increased by 242%. The Cmax, AUC, and Cmin of desacetyl-diltiazem increased by 272%, 265%, and 221%, respectively. There were no significant effects on atazanavir levels.(1) |
ATAZANAVIR SULFATE, DARUNAVIR, EVOTAZ, FOSAMPRENAVIR CALCIUM, PREZCOBIX, PREZISTA, REYATAZ, SYMTUZA |
| Tacrolimus/Selected Calcium Channel Blockers SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Some calcium channel blockers may inhibit the metabolism of tacrolimus by CYP3A4.(1-13) CLINICAL EFFECTS: Concurrent use of calcium channel blockers may result in elevated levels of and side effects from tacrolimus, including nephrotoxicity, neurotoxicity, and prolongation of the QTc interval and life-threatening cardiac arrhythmias, including torsades de pointes.(1-13) PREDISPOSING FACTORS: The risk of QT prolongation or torsade de pointes may be increased in patients with cardiovascular disease (e.g. heart failure, myocardial infarction, history of torsade de pointes, congenital long QT syndrome), hypokalemia, hypomagnesemia, hypocalcemia, bradycardia, female gender, or advanced age. 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 torsade 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, and/or renal/hepatic dysfunction). PATIENT MANAGEMENT: Patients maintained on tacrolimus should be closely monitored if calcium channel blockers such as amlodipine, diltiazem, felodipine, nifedipine, or verapamil are initiated or discontinued. The dosage of tacrolimus may need to be adjusted or the calcium channel blocker may need to be discontinued. When concurrent therapy of selected calcium channel blockers and tacrolimus 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: A study of 9 healthy volunteers who are CYP3A5 expressers found that concomitant tacrolimus and amlodipine resulted in increased tacrolimus AUC by 2.44-fold and 4.1-fold in a single-dose and a 7-day multi-dose study, respectively, compared to tacrolimus alone. No interaction was observed in CYP3A5 non-expressers.(2) However, a case report of a 4-year-old renal transplant patient who is a CYP3A5 non-expresser on tacrolimus and started on amlodipine described increased tacrolimus trough level and AUC from 3.7 to 12.2 ng/mL and 211 to 638 h/ng/mL, respectively.(3) A non-randomized study in 2 liver and 2 renal transplant recipients examined the effects of diltiazem on tacrolimus. In the 2 kidney recipients, concurrent diltiazem at a dosage of 20 mg daily increased tacrolimus AUC by 26% and by 67%. Diltiazem at a dosage of 180 mg increased tacrolimus AUC by 48% and by 177%. In the 2 liver recipients, no tacrolimus increases were seen until diltiazem dosage reached 60 mg daily. One subject received 120 mg of diltiazem daily and tacrolimus AUC was increased by 18%. The other subject received 180 mg diltiazem daily and tacrolimus AUC increased 22%.(4) There is one case report of elevated tacrolimus levels and toxicity in a liver transplant patient 3 days after the addition of diltiazem to his regimen.(5) There is one case report of elevated tacrolimus levels in a renal transplant patient.(6) In contrast, a retrospective review of renal transplant patients found no difference in tacrolimus-related side effects or tacrolimus exposure in patients treated with diltiazem versus those not treated with diltiazem.(7) There is one report of increased tacrolimus levels with concurrent felodipine in a renal transplant patient.(8) A retrospective review examined the effects of nifedipine on tacrolimus dosing requirements in renal transplant patients. In patients who received concurrent nifedipine (n=22), tacrolimus daily dosing requirements were 26%, 29%, and 38% lower at 3, 6, and 12 months post-transplant when compared to patients not taking nifedipine (n=28).(9) In a study of liver transplant patients, nifedipine improved kidney function as indicated by lowering of serum creatinine levels at 6 and 12 months.(10) In vitro studies in human tissue found that tacrolimus metabolism was inhibited by nifedipine and verapamil.(12,13) |
ASTAGRAF XL, ENVARSUS XR, PROGRAF, TACROLIMUS, TACROLIMUS XL |
| Simvastatin (Less than or Equal To 20 mg)/Amlodipine SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Amlodipine may inhibit the metabolism of simvastatin by CYP3A4.(1-7) Levamlodipine is the active isomer of amlodipine.(8) CLINICAL EFFECTS: Concurrent amlodipine may result in elevated levels of simvastatin,(1-7) which may result in myopathy and rhabdomyolysis. PREDISPOSING FACTORS: The risk for myopathy or rhabdomyolysis may be greater in patients 65 years and older, inadequately treated hypothyroidism, renal impairment, carnitine deficiency, malignant hyperthermia, or in patients with a history of myopathy or rhabdomyolysis. Patients with a SLCO1B1 polymorphism that leads to decreased function of the hepatic uptake transporter OATP1B1 may have increased statin concentrations and be predisposed to myopathy or rhabdomyolysis. PATIENT MANAGEMENT: Do not exceed a dosage of 20 mg daily of simvastatin in patients receiving concurrent therapy with amlodipine.(1-4) Consider separating the administration times of amlodipine and simvastatin in patients receiving concurrent therapy with amlodipine and simvastatin doses of 20 mg or less.(5) DISCUSSION: In a study in 8 patients with hypercholesterolemia and hypertension, 4 weeks of concurrent administration of amlodipine (5 mg daily) increased the maximum concentration (Cmax) and area-under-curve (AUC) of simvastatin (5 mg daily) by 43% and 28%, respectively. There were no changes in the lipid-lowering affects of simvastatin.(6) In a study in 17 subjects, administration of amlodipine (5 mg daily) 4 hours after simvastatin (5 mg daily) resulted in Cmax and AUC values of simvastatin that were 63.2% and 66.0%, respectively, of values obtained with simultaneous dosing.(5) Acute renal failure and rhabdomyolysis was reported in patient maintained on amlodipine and alprazolam two days after beginning the maximal dose of simvastatin.(7) |
EZETIMIBE-SIMVASTATIN, SIMVASTATIN, VYTORIN, ZOCOR |
| Selected MAOIs/Selected Antihypertensive Agents SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Both MAOIs and antihypertensive agents may increase the risk of postural hypotension.(1,2) CLINICAL EFFECTS: Postural hypotension may occur with concurrent therapy of MAOIs and antihypertensive agents.(1,2) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The manufacturer of phenelzine states all patients should be followed closely for symptoms of postural hypotension. Hypotensive side effects have occurred in patients who have been hypertensive and normotensive, as well as hypotensive at initiation of phenelzine.(1) The manufacturer of tranylcypromine states hypotension has been observed most commonly but not exclusively in patients with pre-existing hypertension. Tranylcypromine doses greater than 30 mg daily have a major side effect of postural hypotension and can lead to syncope. Gradual dose titration is recommended to decrease risk of postural hypotension. Combined use with other agents known to cause hypotension have shown to have additive side effects and should be monitored closely.(2) Monitor the patient for signs and symptoms of postural hypotension including dizziness, lightheadedness, or weakness, especially upon standing. Monitor blood pressure as well as orthostatic vitals and adjust antihypertensive therapy, including decreasing the dose, dividing doses, or scheduling doses at bedtime, as needed to maintain goal blood pressure. If blood pressure remains hypotensive, consider decreasing the dose of phenelzine or tranylcypromine. In some cases, discontinuation of one or both agents may be necessary.(3) Normotensive patients on stable antihypertensive therapy who are started on either phenelzine or tranylcypromine may be at increased risk for hypotension. Hypertensive patients on stable phenelzine or tranylcypromine who require antihypertensive therapy would be at decreased risk for hypotension. DISCUSSION: A review article describes the pharmacology of phenelzine and tranylcypromine as non-selective MAOIs which inhibit both type A and type B substrates. Orthostatic hypotension is described as the most common MAOI side effect and usually occurs between initiation and the first 3-4 weeks of therapy.(3) In a double-blind study, 71 patients were randomized to receive a 4-week trial of either tranylcypromine, amitriptyline, or the combination. The number of patients reporting dizziness at 4 weeks was not different between the three treatment groups (tranylcypromine 52.4%; amitriptyline 65%; combination 66.7%). Blood pressure (BP) assessment noted a significant drop in standing BP in the tranylcypromine group compared to baseline (systolic BP change = -10 mmHg; p<0.02 and diastolic BP change = -9 mmHg; p<0.02). Combination therapy also had a significant drop in standing BP compared to baseline (systolic BP change = -9 mmHg; p<0.02). Patients receiving amitriptyline had no significant change in BP from baseline at 4 weeks. All three groups had a trend toward increasing orthostatic hypotension in BP changes from lying to standing. The change in orthostatic hypotension was significant in the amitriptyline group with an average systolic BP orthostatic drop of -9 mmHg (p<0.05).(4) A randomized, double-blind study of 16 inpatients with major depressive disorder were treated with either phenelzine or tranylcypromine. Cardiovascular assessments were completed at baseline and after 6 weeks of treatment. After 6 weeks, 5/7 patients (71%) who received phenelzine had a decrease in standing systolic BP greater than 20 mmHg from baseline. Head-up tilt systolic and diastolic BP decreased from baseline in patients on phenelzine (98/61 mmHg v. 127/65 mmHg, respectively; systolic change p=0.02 and diastolic change p=0.02). After 6 weeks, 6/9 patients (67%) who received tranylcypromine had a decrease in standing systolic BP greater than 20 mmHg from baseline. Head-up tilt systolic and diastolic BP decreased from baseline in patients on tranylcypromine (113/71 mmHg v. 133/69 mmHg, respectively; systolic change p=0.09 and diastolic change p=0.07).(5) Selected MAOIs linked to this monograph include: phenelzine and tranylcypromine. Selected antihypertensive agents include: ACE inhibitors, alpha blockers, ARBs, beta blockers, calcium channel blockers, aprocitentan, clonidine, hydralazine and sparsentan. |
NARDIL, PARNATE, PHENELZINE SULFATE, TRANYLCYPROMINE SULFATE |
| Tizanidine/Selected Antihypertensives SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Tizanidine is an alpha-2 agonist. Concurrent use with antihypertensive agents may result in additive effects on blood pressure.(1) CLINICAL EFFECTS: Concurrent use of antihypertensives and tizanidine may result in hypotension.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Patients receiving concurrent therapy should be monitored for hypotension. The risk of hypotension may be decreased by careful titration of tizanidine dosages and monitoring for hypotension prior to dose advancement. Counsel patients about the risk of orthostatic hypotension.(1) DISCUSSION: Severe hypotension has been reported following the addition of tizanidine to existing lisinopril therapy.(2-4) |
TIZANIDINE HCL, ZANAFLEX |
| Lacosamide/Beta-Blockers; Calcium Channel Blockers SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Lacosamide may enhance the slow inactivation of voltage-gated sodium channels and may cause dose-dependent bradycardia, prolongation of the PR interval, atrioventricular (AV) block, or ventricular tachyarrhythmia.(1) CLINICAL EFFECTS: Concurrent use of lacosamide and agents that affect cardiac conduction (beta-blockers, calcium channel blockers) may increase the risk of bradycardia, prolongation of the PR interval, atrioventricular (AV) block, or ventricular tachyarrhythmia.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Lacosamide should be used with caution in patients on concomitant medications that affect cardiac conduction, including beta-blockers and calcium channel blockers.(1) If concurrent use is needed, obtain an ECG before lacosamide therapy and after lacosamide dose is titrated to steady-state.(1) Patients should be monitored closely when lacosamide is given intravenously.(1) DISCUSSION: In a clinical trial in patients with partial-onset seizures, asymptomatic first-degree atrioventricular (AV) block occurred in 4/944 (0.4%) of patient who received lacosamide compared to 0/364 (0%) with placebo.(1) In a clinical trial in patients with diabetic neuropathy, asymptomatic first-degree AV block occurred in 5/1023 (0.5%) of patients who received lacosamide compared to 0/291 (0%) with placebo.(1) Second-degree and complete AV block have been reported in patients with seizures.(1) One case of profound bradycardia was observed in a patient during a 15-minute infusion of 150 mg of lacosamide.(1) Two postmarketing reports of third-degree AV block in patients with significant cardiac history and also receiving metoprolol and amlodipine during infusion of lacosamide injection at doses higher than recommended have been reported.(1) A case report of an 88 year old female taking bisoprolol documented complete AV block after initiation of lacosamide. The patient required pacemaker implementation.(2) |
LACOSAMIDE, MOTPOLY XR, VIMPAT |
| Apomorphine/Selected Antihypertensives and Vasodilators SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Apomorphine causes dose-dependent decreases in blood pressure. Concurrent use with antihypertensive agents may result in additive effects on blood pressure.(1) CLINICAL EFFECTS: Concurrent use of antihypertensives and apomorphine may result in orthostatic hypotension with or without dizziness, nausea, or syncope.(1) PREDISPOSING FACTORS: The risk of orthostatic hypotension may be increased during dose escalation of apomorphine and in patients with renal or hepatic impairment.(1) PATIENT MANAGEMENT: Patients receiving concurrent therapy should be monitored for hypotension. Counsel patients about the risk of orthostatic hypotension.(1) DISCUSSION: Healthy volunteers who took sublingual nitroglycerin (0.4 mg) concomitantly with apomorphine experienced a mean largest decrease in supine systolic blood pressure (SBP) of 9.7 mm Hg and in supine diastolic blood pressure (DBP) of 9.3 mm Hg, and a mean largest decrease in standing SBP and DBP of 14.3 mm Hg and 13.5 mm Hg, respectively. The maximum decrease in SBP and DBP was 65 mm Hg and 43 mm Hg, respectively. When apomorphine was taken alone, the mean largest decrease in supine SBP and DBP was 6.1 mm Hg and 7.3 mm Hg, respectively, and in standing SBP and DBP was 6.7 mm Hg and 8.4 mm Hg, respectively.(1) |
APOKYN, APOMORPHINE HCL, ONAPGO |
| Lemborexant (Less Than or Equal To 5 mg)/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Inhibitors of CYP3A4 may inhibit the metabolism of lemborexant.(1) CLINICAL EFFECTS: Concurrent use of an inhibitor of CYP3A4 may result in increased levels of and effects from lemborexant, including somnolence, fatigue, CNS depressant effects, daytime impairment, headache, and nightmare or abnormal dreams.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The maximum recommended dose of lemborexant with concurrent use of a weak CYP3A4 inhibitors should not exceed 5 mg per dose.(1) DISCUSSION: Lemborexant is a CYP3A4 substrate. In a PKPB model, concurrent use of lemborexant with itraconazole increased area-under-curve (AUC) and concentration maximum (Cmax) by 3.75-fold and 1.5-fold, respectively. Concurrent use of lemborexant with fluconazole increased AUC and Cmax by 4.25-fold and 1.75-fold, respectively.(1) Weak inhibitors of CYP3A4 include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, capivasertib, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, daridorexant, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, mavorixafor, olaparib, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, rucaparib, selpercatinib, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan.(1,2) |
DAYVIGO |
| Ubrogepant/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Weak inhibitors of CYP3A4 may inhibit the metabolism of ubrogepant.(1) CLINICAL EFFECTS: Concurrent use of ubrogepant with weak CYP3A4 inhibitors may result in an increase in exposure of ubrogepant.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The manufacturer recommends a dosage adjustment of ubrogepant when used concomitantly with weak CYP3A4 inhibitors. Initial dose of ubrogepant should not exceed 50 mg when used concomitantly with weak inhibitors of CYP3A4. A second dose may be given within 24 hours but should not exceed 50 mg when used concurrently with weak CYP3A4 inhibitors.(1) DISCUSSION: Coadministration of ubrogepant with verapamil, a moderate CYP3A4 inhibitor, resulted in a 3.5-fold and 2.8-fold increase in area-under-curve (AUC) and concentration maximum (Cmax), respectively. No dedicated drug interaction study was conducted to assess concomitant use with weak CYP3A4 inhibitors. The conservative prediction of the maximal potential increase in ubrogepant exposure with weak CYP3A4 inhibitors is not expected to be more than 2-fold.(1) Weak inhibitors of CYP3A4 include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, berberine, bicalutamide, blueberry, brodalumab, cannabidiol, capivasertib, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clotrimazole, cranberry, cyclosporine, daclatasvir, delavirdine, dihydroberberine, diosmin, elagolix, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lapatinib, larotrectinib, lazertinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, maribavir, mavorixafor, osilodrostat, palbociclib, pazopanib, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, roxithromycin, simeprevir, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, viloxazine, and vonoprazan.(2,3) |
UBRELVY |
| Amlodipine/Apalutamide; Carbamazepine SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Concurrent use of apalutamide or carbamazepine may induce the CYP3A4 mediated metabolism of amlodipine.(1-3) CLINICAL EFFECTS: Concurrent use of apalutamide or carbamazepine may decrease levels and effectiveness of amlodipine.(1-3) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US manufacturer of apalutamide recommends substituting amlodipine with a drug not metabolized by CYP3A4 when possible. If concurrent therapy with apalutamide or carbamazepine is necessary, monitor the patient for a decrease in the therapeutic effects of amlodipine. The dose of amlodipine may need to be adjusted.(1-3) DISCUSSION: Apalutamide is a strong inducer of CYP3A4. Amlodipine is metabolized by CYP3A4 and has been shown to be affected by other strong CYP3A4 inducers. In a study in 16 hypertensive chronic kidney disease patients, amlodipine levels decreased an average of 82% after initiation of rifampin. In eight of the 16 patients, the levels were undetectable.(4) A case report describes a 53-year-old women with schizophrenia and hypertension who was stable on paliperidone and amlodipine 5 mg daily. Upon carbamazepine initiation, amlodipine levels decreased by 68%, and blood pressure increased from a baseline of 138/91 to 160/103. Blood pressure normalized after discontinuation of carbamazepine.(5) |
CARBAMAZEPINE, CARBAMAZEPINE ER, CARBATROL, EPITOL, EQUETRO, ERLEADA, TEGRETOL, TEGRETOL XR |
| Sirolimus Protein-Bound/Slt Moderate and Weak CYP3A4 Inhibit SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Moderate and weak CYP3A4 inhibitors may inhibit the metabolism of sirolimus by CYP3A4.(1) CLINICAL EFFECTS: Concurrent use of moderate or weak CYP3A4 inhibitors may result in elevated levels of and side effects from sirolimus.(1) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The US manufacturer of sirolimus protein-bound injection (Fyarro) states a dose reduction to 56 mg/m2 is recommended when used concurrently with moderate or weak CYP3A4 inhibitors. Concurrent use with strong CYP3A4 inhibitors should be avoided.(1) DISCUSSION: In an open, randomized, cross-over trial in 18 healthy subjects, concurrent single doses of diltiazem (120 mg) and sirolimus (10 mg) increased sirolimus area-under-curve (AUC) and maximum concentration (Cmax) by 60% and by 43%, respectively. Sirolimus apparent oral clearance and volume of distribution decreased by 38% and 45%, respectively. There were no effects on diltiazem pharmacokinetics or pharmacodynamics.(2) In a study in 26 healthy subjects, concurrent sirolimus (2 mg daily) with verapamil (180 mg twice daily) increased sirolimus AUC and Cmax by 2.2-fold and 2.3-fold, respectively. The AUC and Cmax of the active S-enantiomer of verapamil each increased by 1.5-fold. Verapamil time to Cmax (Tmax) was increased by 1.2 hours.(2) Moderate and weak CYP3A4 inhibitors linked to this monograph include: alprazolam, amlodipine, aprepitant, avacopan, azithromycin, berberine, berotralstat, bicalutamide, blueberry, brodalumab, chlorzoxazone, cilostazol, cimetidine, ciprofloxacin, clofazimine, conivaptan, daclatasvir, daridorexant, delavirdine, diosmin, entrectinib, erythromycin, estrogen, flibanserin, fluvoxamine, fosaprepitant, fosnetupitant, fostamatinib, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, grazoprevir, isoniazid, istradefylline, ivacaftor, lacidipine, lazertinib, lenacapavir, levamlodipine, linagliptin, lomitapide, lumateperone, lurasidone, mavorixafor, netupitant, omeprazole, osilodrostat, peppermint oil, piperine, propiverine, propofol, ranitidine, ranolazine, remdesivir, resveratrol, rimegepant, roxithromycin, scutellarin, simeprevir, sitaxsentan, suvorexant, ticagrelor, tofisopam, tolvaptan, trofinetide and vonoprazan.(3,4) |
FYARRO |
| Selected Calcium Channel Blockers/Nirmatrelvir-Ritonavir SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Nirmatrelvir-ritonavir may inhibit the metabolism of calcium channel blockers by CYP3A4.(1,2) CLINICAL EFFECTS: Concurrent use of nirmatrelvir-ritonavir may result in elevated levels of and toxicity from calcium channel blockers. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: Concurrent use of nirmatrelvir-ritonavir and selected calcium channel blockers should be approached with caution. Monitor patients receiving concurrent therapy with nirmatrelvir-ritonavir and either amlodipine, diltiazem, felodipine, nicardipine, nifedipine, or verapamil for increased calcium channel blocker effects. The dosage of the calcium channel blocker may need to be adjusted.(1,2) The Journal of American College of Cardiology recommends a 50% reduction in the dose amlodipine for 8 days with the initiation of nirmatrelvir-ritonavir. Close monitoring of blood pressure and dose reduction or temporary discontinuation of calcium channel blockers may be needed. Resume calcium channel blockers 3 days after the last dose of nirmatrelvir-ritonavir.(3) DISCUSSION: Nirmatrelvir-ritonavir is a strong CYP3A4 inhibitor and may increase the levels of calcium channel blockers that are CYP3A4 substrates.(1,2) In a case report of a 80-year old female on verapamil, on day 2 of concurrent nirmatrelvir-ritonavir the patient presented to the hospital with symptomatic bradycardia (heart rate of 28 beats per minute and blood pressure of 58/35 mmHg) requiring hospitalization, medical management, and a temporary transvenous pacer.(4) |
PAXLOVID |
| Amlodipine; Levamlodipine/Slt Strong CYP3A4 Inhibit SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Strong CYP3A4 inhibitors may inhibit the first-pass and elimination metabolism of calcium channel blockers by CYP3A4. CLINICAL EFFECTS: The concurrent use of strong CYP3A4 inhibitors with calcium channel blockers metabolized by CYP3A4 may result in elevated levels of the calcium channel blocker and risk of adverse effects, including hypotension and bradycardia. PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The concurrent use of strong CYP3A4 inhibitors with calcium channel blockers should be approached with caution. When these agents are used concurrently, the dose of the calcium channel blocker may need to be adjusted or an alternative agent considered. Monitor patients for increased calcium channel blocker effects. If the strong CYP3A4 inhibitor is discontinued, the dose of the calcium channel blocker may need to be increased and patients should be observed for decreased effects. DISCUSSION: Coadministration of a 180 mg dose of diltiazem (moderate CYP3A4 inhibitor) with 5 mg amlodipine resulted in a 60% increase in amlodipine systemic exposure. Strong inhibitor of CYP3A4 may increase plasma concentrations of amlodipine to a greater extent.(1) In a study in 19 healthy subjects, telaprevir (750 mg every 8 hours for 7 days) increased the maximum concentration (Cmax) and area-under-curve (AUC) of a single dose of amlodipine (5mg) by 1.27-fold and 2.79-fold, respectively.(3) Strong CYP3A4 inhibitors include: adagrasib, ceritinib, clarithromycin, cobicistat, fluconazole, idelalisib, indinavir, itraconazole, josamycin, ketoconazole, levoketoconazole, lopinavir, mibefradil, mifepristone, nefazodone, nelfinavir, posaconazole, ribociclib, saquinavir, telithromycin, tipranavir, troleandomycin, tucatinib, and voriconazole.(4,5) |
APTIVUS, CLARITHROMYCIN, CLARITHROMYCIN ER, DIFLUCAN, EVOTAZ, FLUCONAZOLE, FLUCONAZOLE-NACL, GENVOYA, ITRACONAZOLE, ITRACONAZOLE MICRONIZED, KALETRA, KETOCONAZOLE, KISQALI, KORLYM, KRAZATI, LANSOPRAZOL-AMOXICIL-CLARITHRO, LOPINAVIR-RITONAVIR, MIFEPREX, MIFEPRISTONE, NEFAZODONE HCL, NOXAFIL, OMECLAMOX-PAK, POSACONAZOLE, PREZCOBIX, RECORLEV, SPORANOX, STRIBILD, SYMTUZA, TOLSURA, TUKYSA, TYBOST, VFEND, VFEND IV, VIRACEPT, VOQUEZNA TRIPLE PAK, VORICONAZOLE, ZYDELIG, ZYKADIA |
| Mavacamten/Weak CYP3A4 Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Weak CYP3A4 inhibitors may decrease the metabolism of mavacamten.(1) CLINICAL EFFECTS: Concurrent use of weak CYP3A4 inhibitors may increase the plasma levels and the incidence and severity of adverse reactions of mavacamten.(1) PREDISPOSING FACTORS: CYP2C19 poor metabolizers may experience an increased incidence or severity of adverse effects.(1) PATIENT MANAGEMENT: The UK manufacturer of mavacamten states no dose adjustment is necessary when starting mavacamten in patients on weak CYP3A4 inhibitors or in intermediate, normal, rapid, or ultra-rapid CYP2C19 metabolizers already on mavacamten and starting a weak CYP3A4 inhibitor. In poor CYP2C19 metabolizers already on mavacamten and starting a weak CYP3A4 inhibitor, reduce mavacamten 5 mg to 2.5 mg or if on 2.5 mg pause treatment for 4 weeks. If CYP2C19 phenotype is unknown, consider a mavacamten starting dose of 2.5 mg daily.(1) DISCUSSION: In a PBPK model, concomitant use of mavacamten (15 mg daily) with cimetidine 400 mg twice daily, a weak CYP3A4 inhibitor, was predicted to increase mavacamten area-under-curve (AUC) by 6% and maximum concentration (Cmax) by 4% in poor CYP2C19 metabolizers and by 3% and 2%, respectively, in both intermediate and normal CYP2C19 metabolizers.(2) Weak CYP3A4 inhibitors include: alprazolam, amiodarone, amlodipine, asciminib, azithromycin, Baikal skullcap, belumosudil, berberine, bicalutamide, blueberry, brodalumab, chlorzoxazone, cilostazol, ciprofloxacin, clotrimazole, cranberry, cyclosporine, delavirdine, dihydroberberine, diosmin, everolimus, flibanserin, fosaprepitant, fostamatinib, gepotidacin, ginkgo, givinostat, glecaprevir/pibrentasvir, goldenseal, istradefylline, ivacaftor, lacidipine, lapatinib, leflunomide, levamlodipine, linagliptin, lomitapide, lurasidone, mavorixafor, pazopanib, peppermint oil, propiverine, propofol, ranitidine, remdesivir, resveratrol, roxithromycin, sitaxsentan, skullcap, suvorexant, teriflunomide, ticagrelor, tolvaptan, trofinetide, and viloxazine.(4,5) |
CAMZYOS |
The following contraindication information is available for NORVASC (amlodipine besylate):
Drug contraindication overview.
Amlodipine is contraindicated in patients with known hypersensitivity to the drug.
Amlodipine is contraindicated in patients with known hypersensitivity to the drug.
There are 0 contraindications.
There are 3 severe contraindications.
Adequate patient monitoring is recommended for safer drug use.
| Severe List |
|---|
| Severe aortic valve stenosis |
| Severe hepatic disease |
| Severe hypotension |
There are 0 moderate contraindications.
The following adverse reaction information is available for NORVASC (amlodipine besylate):
Adverse reaction overview.
Adverse effects reported in 1% or more of patients receiving amlodipine include edema, dizziness, flushing, palpitations, fatigue, nausea, abdominal pain, and somnolence. Edema, flushing, palpitations, and somnolence may occur more commonly in women than in men. Edema is dose related and may be less frequent with concomitant use of an angiotensin-converting enzyme (ACE) inhibitor or angiotensin II receptor antagonist.
Adverse effects reported in 1% or more of patients receiving amlodipine include edema, dizziness, flushing, palpitations, fatigue, nausea, abdominal pain, and somnolence. Edema, flushing, palpitations, and somnolence may occur more commonly in women than in men. Edema is dose related and may be less frequent with concomitant use of an angiotensin-converting enzyme (ACE) inhibitor or angiotensin II receptor antagonist.
There are 18 severe adverse reactions.
| More Frequent | Less Frequent |
|---|---|
| None. | None. |
| Rare/Very Rare |
|---|
|
Abnormal hepatic function tests Acute myocardial infarction Angioedema Atrial fibrillation Bradycardia Depersonalization Depression Erythema multiforme Extrapyramidal disease Hypotension Jaundice Leukopenia Pancreatitis Progressive angina pectoris Pulmonary edema Purpura Thrombocytopenic disorder Ventricular tachycardia |
There are 59 less severe adverse reactions.
| More Frequent | Less Frequent |
|---|---|
|
Acute abdominal pain Drowsy Edema Headache disorder Nausea Peripheral edema |
Dizziness Fatigue Flushing Palpitations |
| Rare/Very Rare |
|---|
|
Abnormal sexual function Anorexia Arthralgia Back pain Chest pain Chills Conjunctivitis Constipation Cramps Diarrhea Dream disorder Drug-induced hot flash Dysphagia Dyspnea Epistaxis Flatulence General weakness Gingival hyperplasia Gynecomastia Hyperglycemia Hyperhidrosis Hypoesthesia Increased urinary frequency Insomnia Maculopapular rash Malaise Myalgia Nervousness Nocturia Ocular pain Osteoarthritis Paresthesia Peripheral ischemia Peripheral neuropathy Polydipsia Pruritus of skin Skin rash Symptoms of anxiety Syncope Tachycardia Tinnitus Tremor Vasculitis Vertigo Visual changes Vomiting Weight gain Weight loss Xerostomia |
The following precautions are available for NORVASC (amlodipine besylate):
Safety and efficacy of amlodipine in children younger than 6 years of age have not been established. Efficacy of amlodipine (2.5-5 mg daily) for the treatment of hypertension has been established in pediatric patients 6-17 years of age. Safety and efficacy of amlodipine in fixed combination with atorvastatin, benazepril, olmesartan (with or without hydrochlorothiazide), perindopril, telmisartan, or valsartan (with or without hydrochlorothiazide) have not been established in children.
Contraindicated
Severe Precaution
Management or Monitoring Precaution
Contraindicated
| None |
Severe Precaution
| None |
Management or Monitoring Precaution
| None |
Category C. (See Users Guide.)
It is not known whether amlodipine is distributed into milk; the manufacturer recommends discontinuance of nursing if amlodipine is used.
In geriatric patients, amlodipine clearance is decreased and AUC is increased by about 40-60%. Therefore, amlodipine dosage should be selected carefully, usually initiating therapy with dosages at the lower end of the recommended range. The greater frequency of decreased hepatic, renal, and/or cardiac function and of concomitant disease and drug therapy observed in the elderly also should be considered.
(See Geriatric Patients under Dosage and Administration: Special Populations.) Clinical studies of amlodipine did not include sufficient numbers of patients 65 years of age and older to determine whether geriatric patients respond differently than younger patients; however, other clinical experience has not revealed age-related differences in response or tolerance. No substantial differences in safety and efficacy relative to younger adults have been observed in geriatric patients receiving amlodipine in fixed combination with benazepril, olmesartan (with or without hydrochlorothiazide), telmisartan, or valsartan (with or without hydrochlorothiazide), but increased sensitivity cannot be ruled out. The manufacturer states that use of amlodipine in fixed combination with perindopril in geriatric patients is not recommended, as insufficient data are available to support dosage recommendations. The manufacturers state that safety and efficacy of amlodipine in fixed combination with atorvastatin have not been established in geriatric patients.
(See Geriatric Patients under Dosage and Administration: Special Populations.) Clinical studies of amlodipine did not include sufficient numbers of patients 65 years of age and older to determine whether geriatric patients respond differently than younger patients; however, other clinical experience has not revealed age-related differences in response or tolerance. No substantial differences in safety and efficacy relative to younger adults have been observed in geriatric patients receiving amlodipine in fixed combination with benazepril, olmesartan (with or without hydrochlorothiazide), telmisartan, or valsartan (with or without hydrochlorothiazide), but increased sensitivity cannot be ruled out. The manufacturer states that use of amlodipine in fixed combination with perindopril in geriatric patients is not recommended, as insufficient data are available to support dosage recommendations. The manufacturers state that safety and efficacy of amlodipine in fixed combination with atorvastatin have not been established in geriatric patients.
The following prioritized warning is available for NORVASC (amlodipine besylate):
No warning message for this drug.
No warning message for this drug.
The following icd codes are available for NORVASC (amlodipine besylate)'s list of indications:
| Hypertension | |
| I10 | Essential (primary) hypertension |
| I11 | Hypertensive heart disease |
| I11.0 | Hypertensive heart disease with heart failure |
| I11.9 | Hypertensive heart disease without heart failure |
| I12 | Hypertensive chronic kidney disease |
| I12.0 | Hypertensive chronic kidney disease with stage 5 chronic kidney disease or end stage renal disease |
| I12.9 | Hypertensive chronic kidney disease with stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease |
| I13 | Hypertensive heart and chronic kidney disease |
| I13.0 | Hypertensive heart and chronic kidney disease with heart failure and stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease |
| I13.1 | Hypertensive heart and chronic kidney disease without heart failure |
| I13.10 | Hypertensive heart and chronic kidney disease without heart failure, with stage 1 through stage 4 chronic kidney disease, or unspecified chronic kidney disease |
| I13.11 | Hypertensive heart and chronic kidney disease without heart failure, with stage 5 chronic kidney disease, or end stage renal disease |
| I13.2 | Hypertensive heart and chronic kidney disease with heart failure and with stage 5 chronic kidney disease, or end stage renal disease |
| I15.1 | Hypertension secondary to other renal disorders |
| Prevention of anginal pain from vasospastic angina | |
| I20.1 | Angina pectoris with documented spasm |
| I25.111 | Atherosclerotic heart disease of native coronary artery with angina pectoris with documented spasm |
| I25.701 | Atherosclerosis of coronary artery bypass graft(s), unspecified, with angina pectoris with documented spasm |
| I25.711 | Atherosclerosis of autologous vein coronary artery bypass graft(s) with angina pectoris with documented spasm |
| I25.721 | Atherosclerosis of autologous artery coronary artery bypass graft(s) with angina pectoris with documented spasm |
| I25.731 | Atherosclerosis of nonautologous biological coronary artery bypass graft(s) with angina pectoris with documented spasm |
| I25.751 | Atherosclerosis of native coronary artery of transplanted heart with angina pectoris with documented spasm |
| I25.761 | Atherosclerosis of bypass graft of coronary artery of transplanted heart with angina pectoris with documented spasm |
| I25.791 | Atherosclerosis of other coronary artery bypass graft(s) with angina pectoris with documented spasm |
| Prevention of anginal pain in coronary artery disease | |
| I20.2 | Refractory angina pectoris |
| I20.81 | Angina pectoris with coronary microvascular dysfunction |
| I20.89 | Other forms of angina pectoris |
| I20.9 | Angina pectoris, unspecified |
| I25.112 | Atherosclerotic heart disease of native coronary artery with refractory angina pectoris |
| I25.118 | Atherosclerotic heart disease of native coronary artery with other forms of angina pectoris |
| I25.119 | Atherosclerotic heart disease of native coronary artery with unspecified angina pectoris |
| I25.702 | Atherosclerosis of coronary artery bypass graft(s), unspecified, with refractory angina pectoris |
| I25.708 | Atherosclerosis of coronary artery bypass graft(s), unspecified, with other forms of angina pectoris |
| I25.709 | Atherosclerosis of coronary artery bypass graft(s), unspecified, with unspecified angina pectoris |
| I25.712 | Atherosclerosis of autologous vein coronary artery bypass graft(s) with refractory angina pectoris |
| I25.718 | Atherosclerosis of autologous vein coronary artery bypass graft(s) with other forms of angina pectoris |
| I25.719 | Atherosclerosis of autologous vein coronary artery bypass graft(s) with unspecified angina pectoris |
| I25.722 | Atherosclerosis of autologous artery coronary artery bypass graft(s) with refractory angina pectoris |
| I25.728 | Atherosclerosis of autologous artery coronary artery bypass graft(s) with other forms of angina pectoris |
| I25.729 | Atherosclerosis of autologous artery coronary artery bypass graft(s) with unspecified angina pectoris |
| I25.732 | Atherosclerosis of nonautologous biological coronary artery bypass graft(s) with refractory angina pectoris |
| I25.738 | Atherosclerosis of nonautologous biological coronary artery bypass graft(s) with other forms of angina pectoris |
| I25.739 | Atherosclerosis of nonautologous biological coronary artery bypass graft(s) with unspecified angina pectoris |
| I25.752 | Atherosclerosis of native coronary artery of transplanted heart with refractory angina pectoris |
| I25.758 | Atherosclerosis of native coronary artery of transplanted heart with other forms of angina pectoris |
| I25.759 | Atherosclerosis of native coronary artery of transplanted heart with unspecified angina pectoris |
| I25.762 | Atherosclerosis of bypass graft of coronary artery of transplanted heart with refractory angina pectoris |
| I25.768 | Atherosclerosis of bypass graft of coronary artery of transplanted heart with other forms of angina pectoris |
| I25.769 | Atherosclerosis of bypass graft of coronary artery of transplanted heart with unspecified angina pectoris |
| I25.792 | Atherosclerosis of other coronary artery bypass graft(s) with refractory angina pectoris |
| I25.798 | Atherosclerosis of other coronary artery bypass graft(s) with other forms of angina pectoris |
| I25.799 | Atherosclerosis of other coronary artery bypass graft(s) with unspecified angina pectoris |
Formulary Reference Tool