Dipyridamole

Drug overview for DIPYRIDAMOLE (dipyridamole):

Generic name: DIPYRIDAMOLE
Drug class: Antiplatelet Drugs-excluding ASA 325 mg and below
Therapeutic class: Diagnostic Agents

Dipyridamole is a non-nitrate coronary vasodilator that also inhibits platelet aggregation.

No enhanced Uses information available for this drug.

DRUG IMAGES

DIPYRIDAMOLE 50 MG/10 ML VIAL

The following indications for DIPYRIDAMOLE (dipyridamole) have been approved by the FDA:

Indications:
Myocardial perfusion image, adjunct

Professional Synonyms:
Adjunct myocardial perfusion imaging

The following dosing information is available for DIPYRIDAMOLE (dipyridamole):

Dosing
Administration
DIPYRIDAMOLE
DIPYRIDAMOLE

The usual adult oral dosage of dipyridamole for adjunctive use with coumarin anticoagulant (e.g., warfarin) therapy in the prevention of postoperative thromboembolic complications of cardiac valve replacement is 75-100 mg 4 times daily.

For the prevention of thromboembolic complications in patients with various other thromboembolic disorders+, oral dosage of dipyridamole generally has ranged from 150-400 mg daily, in combination with another platelet-aggregation inhibitor (e.g., aspirin) or warfarin.

For reducing the risk of stroke in patients who have had transient ischemic attacks (TIAs) or completed stroke caused by thrombosis, the usual dosage of oral extended-release dipyridamole is 200 mg in fixed combination with aspirin 25 mg (1 capsule) twice daily in the morning and evening. If headaches become intolerable during initial treatment, the dosage of the dipyridamole/aspirin fixed combination should be reduced to 200 mg of dipyridamole and 25 mg of aspirin (1 capsule) once daily at bedtime and low-dose aspirin should be administered in the morning. Because no outcome data are available with this regimen and headaches diminish during continued treatment, patients should resume the usual regimen (200 mg of extended-release dipyridamole and 25 mg of aspirin twice daily) as soon as possible (usually within 1 week).

The amount of aspirin in the fixed-combination preparation may not be adequate to prevent recurrent myocardial infarction (MI) or angina pectoris in patients with stroke or TIA.

When used as an adjunct to thallium myocardial imaging, dipyridamole usually is administered as a single IV dose of 0.57 mg/kg, infused at a rate of 0.142 mg/kg per minute for 4 minutes.

Although the maximum tolerated IV dose of dipyridamole has not been determined, clinical experience suggests that a total dose exceeding 60 mg is not needed for any patient. Thallium-201 should be injected within 5 minutes following completion of the dipyridamole infusion.

Dipyridamole is administered orally or IV. Capsules containing the fixed-combination of extended-release dipyridamole and aspirin should be swallowed whole and should not be chewed. The fixed-combination capsules containing extended-release dipyridamole and aspirin may be administered without regard to food.

Prior to IV administration, dipyridamole injection should be diluted in at least twice the injection volume with 0.45% sodium chloride injection, 0.9% sodium chloride injection, or 5% dextrose injection to a final volume of approximately 20-50 mL. Infusion of undiluted dipyridamole may cause local irritation.

Dosing information for DIPYRIDAMOLE
DRUG LABEL	DOSING TYPE	DOSING INSTRUCTIONS
DIPYRIDAMOLE 50 MG/10 ML VIAL	Maintenance	Adults infuse 0.57 mg/kg over 4 minute(s) by intravenous route once

Generic dosing information for DIPYRIDAMOLE
DRUG LABEL	DOSING TYPE	DOSING INSTRUCTIONS
DIPYRIDAMOLE 50 MG/10 ML VIAL	Maintenance	Adults infuse 0.57 mg/kg over 4 minute(s) by intravenous route once

The following drug interaction information is available for DIPYRIDAMOLE (dipyridamole):

Contraindicated
Severe
Moderate

There are 3 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
Adenosine; Regadenoson/Dipyridamole 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: Dipyridamole inhibits cellular transport of adenosine.(1-3) Also, dipyridamole has been shown to increase intrinsic adenosine levels indicating that dipyridamole inhibits the intrinsic metabolism of adenosine.(4) Regadenoson is a derivative of adenosine.(5) CLINICAL EFFECTS: Concurrent dipyridamole may increase serum concentrations and potentiate the cardiovascular effects of adenosine. Conversely, significant bradycardia has occurred following rapid bolus injections of adenosine.(1-8) Dipyridamole may increase the effects of regadenoson.(1,2,5) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The recommendations for concurrent use of adenosine or regadenoson with dipyridamole is dependent on the indication. -For Cardioversion: The Australian manufacturer of adenosine states the use of adenosine for cardioversion is contraindicated in patients receiving dipyridamole. Discontinue the use of dipyridamole 24 hours prior to adenosine bolus dosing.(7) The US manufacturer of adenosine states smaller doses of adenosine may be effective with dipyridamole.(6) Lower the dose of adenosine in patients receiving dipyridamole.(1,2) Monitor for increased effects of adenosine. -For Stress Testing: Clinical practice guidelines from the American Society of Nuclear Cardiology state dipyridamole use within the previous 48 hours is a contraindication to adenosine or regadenoson stress testing.(9,10) The US manufacturer of dipyridamole recommends stopping dipyridamole for 48 hours prior to stress testing with intravenous dipyridamole or other adenosinergic agents (e.g. adenosine or regadenoson).(1) The Australian manufacturer of dipyridamole recommends stopping dipyridamole for 24 hours prior to stress testing with adenosine.(2) The US manufacturer of regadenoson recommends withholding dipyridamole for at least 2 days prior to regadenoson administration.(5) DISCUSSION: In a prospective, placebo-controlled single blinded study in eight healthy subjects, all patients were randomized to receive adenosine infusion on two separate days. Heart rate and skin temperature increased in a dose-related manner following adenosine administration. An increase in heart rate of 15 bpm occurred with 0.005 mg/kg/min of adenosine following administration of dipyridamole but did not change following saline. Blood pressure remained unchanged throughout the study.(11) According to another prospective, non-placebo controlled, non-blinded study, five healthy volunteers received a five-day course of oral dipyridamole 100 mg every 6 hours. Plasma adenosine levels were measured for a five day control period as a baseline and also during the five-day course of dipyridamole. It was found during the baseline studies that adenosine levels vary significantly between individuals but seem to be constant within the same individual. During the five-day course, the average increase in endogenous adenosine concentration was 60%. It was concluded that administration of oral dipyridamole significantly increases plasma adenosine levels in normal human subjects. Also, there was a positive correlation between adenosine and dipyridamole levels (p = 0.001).(12)	ADENOSINE, LEXISCAN, REGADENOSON
Dipyridamole Injectable/Xanthine Derivatives 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: The xanthine derivatives are adenosine receptor antagonists. Concurrent administration may inhibit dipyridamole-induced increases in endogenous plasma adenosine levels, thus decreasing dipyridamole's vasodilator effects.(1) CLINICAL EFFECTS: Concurrent administration may result in a decrease in dipyridamole's vasodilator effects. This may produce false-negative results during dipyridamole-thallium imaging tests.(1-3) PREDISPOSING FACTORS: In patients with congestive heart failure and decreased hepatic function, the metabolism of xanthine derivatives may be decreased. These patients may need a longer xanthine-free period prior to dipyridamole-thallium imaging tests.(2) PATIENT MANAGEMENT: Patients scheduled for dipyridamole-thallium imaging tests should have a xanthine-free period (including caffeine-containing products) for at least 24 hours prior to their exam.(3) DISCUSSION: In a study in eight male subjects with documented coronary artery disease, intravenous dipyridamole administered during a dipyridamole-thallium 201 SPECT image test produced a significant increase in heart rate, a decrease in blood pressure, and angina in seven patients and ST segment depression in four patients. SPECT imaging showed reversible perfusion defects in myocardial segments supplied by stenotic coronary arteries. When the exam was repeated when the subjects were receiving therapeutic dosages of theophylline, there was no appearance of angina, ST depression, or hemodynamic changes and SPECT imaging shown total absence of reversible perfusion defects.(1) A study in eight patients with coronary artery disease evaluated the effects of caffeine on dipyridamole-201Tl myocardial imaging. The administration of dipyridamole alone resulted in chest pain and ST-segment depression in four patients. Concurrent caffeine infusion decreased the dipyridamole-induced decrease in blood pressure and heart rate. No patients experience chest pain or ST-segment depression. Six patients had false negative test results.(2) Another study found that the attenuation of the hemodynamic response to dipyridamole by caffeine was dose-dependent.(3)	ACETAMIN-CAFF-DIHYDROCODEINE, AMINOPHYLLINE, ASA-BUTALB-CAFFEINE-CODEINE, ASCOMP WITH CODEINE, BUTALB-ACETAMINOPH-CAFF-CODEIN, BUTALBITAL-ACETAMINOPHEN-CAFFE, BUTALBITAL-ASPIRIN-CAFFEINE, CAFCIT, CAFFEINE, CAFFEINE AND SODIUM BENZOATE, CAFFEINE CITRATE, DYPHYLLINE, ELIXOPHYLLIN, ERGOTAMINE-CAFFEINE, FIORICET, FIORICET WITH CODEINE, MIGERGOT, NORGESIC, NORGESIC FORTE, ORPHENADRINE-ASPIRIN-CAFFEINE, ORPHENGESIC FORTE, THEO-24, THEOPHYLLINE, THEOPHYLLINE ANHYDROUS, THEOPHYLLINE ER, THEOPHYLLINE ETHYLENEDIAMINE, TREZIX
Riociguat/PDE 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: Riociguat stimulates the nitric oxide-soluble guanylate cyclase-cyclic guanosine monophosphate (cGMP) pathway and also increases cGMP.(1) Aminophylline, avanafil, dipyridamole, sildenafil, tadalafil, theophylline, and vardenafil inhibit phosphodiesterase (PDE), which is responsible for the breakdown of cGMP.(1) CLINICAL EFFECTS: The concurrent use of PDE inhibitors and riociguat potentiates the hypotensive effects of both agents, which may result in dizziness, syncope, heart attack, or stroke.(1) PREDISPOSING FACTORS: Plasma levels of the PDE type-5 inhibitors may be higher in the following patients: those older than 65, with hepatic impairment, with severe renal impairment, or using concomitant CYP3A4 inhibitors. This may increase the severity of the interaction. PATIENT MANAGEMENT: The administration of riociguat to patients receiving PDE inhibitors, including specific PDE-5 inhibitors (avanafil (5), sildenafil (2), tadalafil (3,6), or vardenafil (4)) and nonspecific PDE inhibitors (aminophylline, dipyridamole, theophylline) is contraindicated.(1) If transitioning from sildenafil to riociguat, discontinue sildenafil at least 24 hours prior to administering riociguat.(1) If transitioning from tadalafil to riociguat, discontinue tadalafil at least 48 hours prior to administering riociguat. Consider starting riociguat at 0.5 mg in patients at risk for hypotension.(1) If transitioning from riociguat to a PDE inhibitor, discontinue riociguat at least 24 hours prior to administering a PDE inhibitor.(1) DISCUSSION: In a study of 7 PAH patients maintained on sildenafil (20 mg TID), single doses of riociguat (0.5 mg and 1 mg, sequentially) showed additive hemodynamic effects.(1) In clinical trials, there was a high rate of discontinuation for hypotension among patients receiving sildenafil (20 mg TID) and riociguat (1 mg to 2.5 mg TID) and one death.(1)	ADEMPAS

There are 8 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 Platelet Aggregation Inhibitors/NSAIDs; Salicylates SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Abciximab, cangrelor, cilostazol, clopidogrel, dipyridamole, eptifibatide, prasugrel, ticagrelor, vorapaxar and NSAIDs or salicylates inhibit platelet aggregation. CLINICAL EFFECTS: Concurrent use of platelet aggregation inhibitors and NSAIDs or salicylates may increase the risk of bleeding. PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with multiple disease-associated factors (e.g. thrombocytopenia, advanced liver disease). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g., anticoagulants, other antiplatelets, corticosteroids, selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs). Risk of GI bleed may be increased in patients who are of older age, in poor health status, or who use alcohol or smoke. Risk may also be increased with longer duration of NSAID use and prior history of peptic ulcer disease and/or GI bleeding. Risk increases as the number of risk factors increases. PATIENT MANAGEMENT: Use caution when administering platelet aggregation inhibitors with NSAIDs or salicylates.(1-5) It would be prudent to monitor patients more closely during concurrent therapy and to use the lowest NSAID or salicylate dose possible. If concurrent therapy is warranted, monitor patients for signs of blood loss, including decreased hemoglobin and/or hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. The 2010 ACCF/ACG/AHA Consensus guidelines recommend the use of proton pump inhibitors (PPIs) in patients with multiple risk factors for GI bleeding who require antiplatelet therapy. However, esomeprazole and omeprazole should be avoided with clopidogrel as they are expected to reduce the effectiveness of clopidogrel. Use of other PPIs should be approached with caution, as they may reduce the effectiveness of clopidogrel. DISCUSSION: Because of the increased risk of bleeding, caution is warranted when using this combination. In a nationwide cohort study, patients were evaluated for thromboembolic cardiovascular and clinically relevant bleeding events with concurrent antithrombotic and ongoing NSAID treatment. A total of 108,232 patients were followed for a mean of 2.3 +/- 1.8 years after diagnosis of myocardial infarction. Concomitant NSAID treatment significantly increased the risk for cardiovascular events (hazard ratio (HR) 6.96; 95% CI 6.24 - 6.77; p<0.001) and bleeding events (HR 4.08; 95% CI 3.51 - 4.73; p<0.001) compared to no NSAID treatment. NSAIDs were further evaluated and revealed the use of celecoxib (HR: 4.65; 95% CI: 3.17 to 6.82; p < 0.001, and 3.44; 95% CI: 2.20 to 5.39; p < 0.001, respectively) and meloxicam (HR: 3.03; 95% CI: 1.68 to 5.47; p < 0.001, and 2.80; 95% CI: 1.40 to 5.60; p < 0.001, respectively) had the lowest risk for cardiovascular and bleeding events, receptively.	ANAPROX DS, ANJESO, ARTHROTEC 50, ARTHROTEC 75, BISMUTH SUBSALICYLATE, BROMFENAC SODIUM, CALDOLOR, CELEBREX, CELECOXIB, CHOLINE MAGNESIUM TRISALICYLAT, COMBOGESIC, COMBOGESIC IV, CONSENSI, COXANTO, DAYPRO, DICLOFENAC, DICLOFENAC POTASSIUM, DICLOFENAC SODIUM, DICLOFENAC SODIUM ER, DICLOFENAC SODIUM MICRONIZED, DICLOFENAC SODIUM-MISOPROSTOL, DIFLUNISAL, DISALCID, DOLOBID, EC-NAPROSYN, ELYXYB, ETODOLAC, ETODOLAC ER, FELDENE, FENOPROFEN CALCIUM, FENOPRON, FLURBIPROFEN, HYDROCODONE-IBUPROFEN, IBU, IBUPAK, IBUPROFEN, IBUPROFEN LYSINE, IBUPROFEN-FAMOTIDINE, INDOCIN, INDOMETHACIN, INDOMETHACIN ER, INFLAMMACIN, INFLATHERM(DICLOFENAC-MENTHOL), KETOPROFEN, KETOPROFEN MICRONIZED, KETOROLAC TROMETHAMINE, KIPROFEN, LODINE, LOFENA, LURBIPR, MECLOFENAMATE SODIUM, MEFENAMIC ACID, MELOXICAM, NABUMETONE, NABUMETONE MICRONIZED, NALFON, NAPRELAN, NAPROSYN, NAPROTIN, NAPROXEN, NAPROXEN SODIUM, NAPROXEN SODIUM CR, NAPROXEN SODIUM ER, NAPROXEN-ESOMEPRAZOLE MAG, NEOPROFEN, OXAPROZIN, PHENYL SALICYLATE, PHENYLBUTAZONE, PIROXICAM, RELAFEN DS, SALSALATE, SODIUM SALICYLATE, SULINDAC, SUMATRIPTAN SUCC-NAPROXEN SOD, SYMBRAVO, TOLECTIN 600, TOLMETIN SODIUM, TORONOVA II SUIK, TORONOVA SUIK, TRESNI, TREXIMET, VIMOVO, VIVLODEX, ZIPSOR, ZORVOLEX, ZYNRELEF
Dabigatran/Antiplatelets; Aspirin (Greater Than 100 mg) SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Dabigatran is a direct thrombin inhibitor and when taken with agents that effect platelet aggregation increased bleeding episodes can occur.(1,2) CLINICAL EFFECTS: Concurrent use of dabigatran with antiplatelet agents may result in additive or synergistic effects resulting in unwanted bleeding episodes.(1,2) PREDISPOSING FACTORS: Factors associated with an increase risk for bleeding include renal impairment, concomitant use of P-glycoprotein inhibitors, patient age >74 years, coexisting conditions (e.g. recent trauma) or use of drugs (e.g. NSAIDs) associated with bleeding risk, and patient weight <50 kg.(1-3) The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Patients requiring concurrent therapy with dabigatran and an antiplatelet agent should be closely monitored for signs of bleeding. 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. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. The time of highest risk for a coumarin-type drug interaction is when the precipitant drug is initiated or discontinued. Contact the prescriber before initiating, altering the dose or discontinuing either drug. Discontinue dabigatran in patients with active bleeding. DISCUSSION: Dabigatran is a direct thrombin inhibitor and when taken with agents that effect platelet aggregation and/or other clotting factors increased bleeding episodes can occur.(1,2) In the RE-LY trial, 40% of patients were on aspirin at baseline.(1) In the RE-MEDY trial, 7.7% of patients were on aspirin at baseline.(1) In the RE-DUAL PCI trial, patients were randomly assigned to one of three treatments: (A) dual therapy with dabigatran 110 mg twice daily plus either clopidogrel or ticagrelor, (B) dual therapy with dabigatran 150 mg twice daily plus either clopidogrel or ticagrelor, or (C) triple therapy with warfarin (goal INR 2-3) plus aspirin (< or = 100 mg daily) plus either clopidogrel or ticagrelor. The incidence of the first major or clinically relevant non-major (CRNM) bleeding event was 15.4% in group A compared with 26.9% in group C (hazard ratio, 0.52; 95% CI 0.42 to 0.63; p<0.001 for noninferiority; p<0.001 for superiority) and 20.2% in group B compared to 25.7% in corresponding group C (hazard ratio, 0.72; 95% CI 0.58 to 0.88; p<0.001 for noninferiority). For major bleeding as defined by Thrombolysis in Myocardial Infarction (TIMI) criteria, the rate was lower in both dual-therapy groups than in the triple-therapy group: 1.4% in group A compared to 3.8% in group C (hazard ratio, 0.37; 95% CI 0.2 to 0.68; p=0.002) and 2.1% in group B compared to 3.9% in corresponding group C (hazard ratio, 0.51; 95% CI 0.28 to 0.93; p=0.03). Incidence of composite efficacy end point of thromboembolic events (myocardial infarction, stroke, or systemic embolism), death, or unplanned revascularization was 13.7% in groups A and B compared to 13.4% in group C (hazard ratio, 1.04; 95% CI 0.84 to 1.29; p=0.005 for noninferiority).(4) A meta-analysis of 9 studies identified 13,459 patients taking direct oral anticoagulants (DOACs), 1,692 of whom also took an antiplatelet agent. Of the patients on antiplatelet agents, 1,254 took aspirin while the rest was unspecified. Most of the trials restricted patients to use of low-dose aspirin, with the highest allowable dose being 165 mg/day. Compared with DOACs alone, the use of DOACs with antiplatelet agents was associated with an increased risk of major bleeding (OR 1.89; 95% CI, 1.04-3.44) and CRNM bleeding (OR 1.82; 95% CI, 1.50-2.22). There was no difference between groups in the efficacy outcome of symptomatic recurrent venous thromboembolism (VTE) or VTE-related death.(5)	DABIGATRAN ETEXILATE, PRADAXA
Rivaroxaban/Selected Antiplatelets; Aspirin (Greater Than 100 mg) SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Additive effects on hemostasis.(1) CLINICAL EFFECTS: Concurrent use of rivaroxaban with anticoagulants, antiplatelets, or thrombolytics may increase the risk of bleeding.(1) PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Avoid concurrent use of rivaroxaban and higher doses of aspirin unless the benefit is expected to outweigh the increased risk of bleeding. In the ROCKET AF trial, concomitant use of low dose aspirin (almost exclusively at less than or equal to 100 mg daily) was identified as an independent risk factor for bleeding.(1) If the benefit of concurrent use of rivaroxaban with other antiplatelets is expected to outweigh the increased risk of bleeding, closely monitor patients for signs or symptoms of bleeding.(1) The UK manufacturer of rivaroxaban states that rivaroxaban 2.5 mg twice daily is indicated with aspirin 75 - 100 mg with or without clopidogrel 75 mg or standard dose ticlopidine for post-acute coronary syndrome and in patients with CAD and PAD, weighing the risk for ischemic events against the bleeding risks. Long-term dual antiplatelet therapy should be avoided. Clinical monitoring is recommended throughout treatment.(2) If concurrent therapy is warranted, monitor patients receiving concurrent therapy for signs of blood loss, including decreased hemoglobin and/or hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. The time of highest risk for a coumarin-type drug interaction is when the precipitant drug is initiated or discontinued. Contact the prescriber before initiating, altering the dose or discontinuing either drug. DISCUSSION: In two clinical trials in healthy subjects, concurrent clopidogrel (300 mg loading dose, then 75 mg daily) and rivaroxaban (15 mg single dose) increased bleeding time to 45 minutes in 45% and 30% of subjects. This was twice the maximum increase in bleeding time seen with either agent alone.(1) In the ROCKET AF trial, concomitant aspirin use (almost exclusively at < or = to 100 mg daily) was identified as an independent risk factor for bleeding.(1) In a study, concurrent enoxaparin (40 mg) and rivaroxaban (10 mg) resulted in additive effects on anti-factor Xa activity with no effects on the pharmacokinetics of rivaroxaban.(1) In a study, concurrent warfarin (15 mg) and rivaroxaban (5 mg) resulted in additive effects on factor Xa inhibition and PT with no effects on the pharmacokinetics of rivaroxaban.(1) In a single dose study, there were no pharmacokinetic or pharmacodynamic interactions between rivaroxaban and aspirin.(1) A self-controlled case study of 1,622 oral anticoagulant-precipitant drug pairs were reviewed and found 14% of drug pairs were associated with a statistically significant elevated risk of thromboembolism. Concurrent use of rivaroxaban and dipyridamole resulted in a ratio of rate ratios (95% CI) of 3.49 (1.08-6.64); and rivaroxaban and aspirin ratio of rate ratios 2.19 (1.21-2.95).(3) A meta-analysis of 9 studies identified 13,459 patients taking direct oral anticoagulants (DOACs), 1,692 of whom also took an antiplatelet agent. Of the patients on antiplatelet agents, 1,254 took aspirin while the rest was unspecified. Most of the trials restricted patients to use of low-dose aspirin, with the highest allowable dose being 165 mg/day. The use of DOACs with antiplatelet agents was associated with an increased risk of major bleeding (OR 1.89; 95% CI, 1.04-3.44) and clinically relevant non-major bleeding (OR 1.82; 95% CI, 1.50-2.22). There was no difference between groups in the efficacy outcome of symptomatic recurrent venous thromboembolism (VTE) or VTE-related death.(4)	RIVAROXABAN, XARELTO
Apixaban/Antiplatelets; Aspirin (Greater Than 100 mg) SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Additive effects on hemostasis.(1-4) CLINICAL EFFECTS: Concurrent use of apixaban with antiplatelets may increase the risk of bleeding.(1-4) PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Patients requiring concurrent therapy with apixaban and an antiplatelet agent should be closely monitored for signs of bleeding. Monitor patients receiving concurrent therapy for signs of blood loss, including decreased hemoglobin and/or hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. Discontinue apixaban in patients with active bleeding. The time of highest risk for a coumarin-type drug interaction is when the precipitant drug is initiated or discontinued. Contact the prescriber before initiating, altering the dose or discontinuing either drug. DISCUSSION: Concurrent administration of enoxaparin (40 mg single dose) and apixaban (5 mg single dose) resulted in additive effects on anti-Factor Xa activity.(1) Concurrent apixaban and aspirin (325 mg daily) resulted in no pharmacokinetic or pharmacodynamic interactions.(1) Concurrent apixaban with clopidogrel (75 mg daily) or with combination clopidogrel (75 mg daily) and aspirin (162 mg daily) produced no relevant increases in bleeding time, platelet aggregation, or clotting tests (PI, INR, and aPTT) compared either clopidogrel alone or clopidogrel with aspirin without apixaban.(1) Significant bleeding risk was reported with the combination of apixaban, aspirin, and clopidogrel in patients with acute coronary syndrome.(1) A self-controlled case study of 1,622 oral anticoagulant-precipitant drug pairs were reviewed and found 14% of drug pairs were associated with a statistically significant elevated risk of thromboembolism. Concurrent use of apixaban and clopidogrel resulted in a ratio of rate ratios (95% CI) of 1.96 (1.53-2.51).(5) A meta-analysis of 9 studies identified 13,459 patients taking direct oral anticoagulants (DOACs), 1,692 of whom also took an antiplatelet agent. Of the patients on antiplatelet agents, 1,254 took aspirin while the rest was unspecified. Most of the trials restricted patients to use of low-dose aspirin, with the highest allowable dose being 165 mg/day. The use of DOACs with antiplatelet agents was associated with an increased risk of major bleeding (OR 1.89; 95% CI, 1.04-3.44) and clinically relevant non-major bleeding (OR 1.82; 95% CI, 1.50-2.22). There was no difference between groups in the efficacy outcome of symptomatic recurrent venous thromboembolism (VTE) or VTE-related death.(3)	ELIQUIS
Edoxaban/Antiplatelets; Aspirin (Greater Than 100 mg) SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Anticoagulants and antiplatelet agents have additive effects on hemostasis.(1) In addition, aspirin doses greater than or equal to 325 mg daily increase edoxaban exposure.(1) CLINICAL EFFECTS: Concurrent use of edoxaban with antiplatelets may increase the risk of bleeding.(1) PREDISPOSING FACTORS: Bleeding risk may be increased in patients with renal impairment and in patients > 75 years of age.(1) Use of multiple agents which affect hemostasis increases the risk for bleeding. The risk for bleeding episodes may be greater in patient with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Patients requiring concurrent therapy with edoxaban and an antiplatelet agent should be closely monitored for signs of bleeding. Edoxaban and aspirin at dosages of 100 mg or less may be coadministered.(2,3) Monitor patients receiving concurrent therapy for signs of blood loss, including decreased hemoglobin and/or hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. 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. Discontinue edoxaban in patients with active bleeding. DISCUSSION: Concomitant use of edoxaban and antiplatelet agents may increase the risk of bleeding. In edoxaban clinical trials concomitant use of low dose aspirin (< or = 100 mg daily), thienopyridines, and NSAIDs was permitted and resulted in increased rates of clinically relevant bleeding. The rates of major bleeding on edoxaban and warfarin were generally consistent among subgroups. Bleeding rates appeared higher in both treatment arms (edoxaban and warfarin) in patients taking aspirin. Co-administration of aspirin (100 mg or 325 mg) and edoxaban increased bleeding time relative to that seen with either drug alone.(1) About 30% of the population in ENGAGE-AF received concomitant therapy with aspirin because of co-morbid conditions. While aspirin is known to increase risk for bleeds and the annualized event rate for major bleeds was higher than that in patients not receiving aspirin (3.87% vs. 2.13%), the risk for bleeds in patients receiving edoxaban 60 mg on a background of aspirin was lower than that for warfarin on a background of aspirin (HR 0.78 (95%CI 0.65,0.94). Based on these data no dose adjustments/contraindications are required.(4) Edoxaban and aspirin at dosages of 100 mg or less may be coadministered.(2,3) A meta-analysis of 9 studies identified 13,459 patients taking direct oral anticoagulants (DOACs), 1,692 of whom also took an antiplatelet agent. Of the patients on antiplatelet agents, 1,254 took aspirin while the rest was unspecified. Most of the trials restricted patients to use of low-dose aspirin, with the highest allowable dose being 165 mg/day. The use of DOACs with antiplatelet agents was associated with an increased risk of major bleeding (OR 1.89; 95% CI, 1.04-3.44) and clinically relevant non-major bleeding (OR 1.82; 95% CI, 1.50-2.22). There was no difference between groups in the efficacy outcome of symptomatic recurrent venous thromboembolism (VTE) or VTE-related death.(5)	SAVAYSA
Cladribine/Selected Inhibitors of CNT or ENT SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Inhibitors of concentrative nucleoside transporters (CNT) or equilibrative nucleoside transporters (ENT) may increase the absorption of cladribine.(1-2) CLINICAL EFFECTS: The concurrent administration of cladribine with an inhibitor of CNT or ENT may result in elevated levels of cladribine and signs of toxicity.(1-2) PREDISPOSING FACTORS: None determined. PATIENT MANAGEMENT: The manufacturer of cladribine states concurrent use of CNT or ENT inhibitors should be avoided during the 4- to 5-day cladribine treatment.(1-2) Selection of an alternative concurrent medication with no or minimal transporter inhibiting proprieties should be considered. If this is not possible, dose reduction to the minimum mandatory dose of the CNT or ENT inhibitor, separation in timing of administration, and careful patient monitoring is recommended.(1-2) Monitor for signs of hematologic toxicity. Lymphocyte counts should be monitored. DISCUSSION: Cladribine is a substrate of CNT and ENT. Inhibitors of these transporters are expected to increase cladribine levels.(1-2) Nucleoside inhibitors linked to this monograph include: cilostazol, dipyridamole, nifedipine, nimodipine, reserpine, and sulindac.(1-2)	CLADRIBINE, MAVENCLAD
Vericiguat/PDE Inhibitors SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Vericiguat stimulates the nitric oxide-soluble guanylate cyclase-cyclic guanosine monophosphate (cGMP) pathway and also increases cGMP.(1) Aminophylline, avanafil, dipyridamole, sildenafil, tadalafil, theophylline, and vardenafil inhibit phosphodiesterase (PDE), which is responsible for the breakdown of cGMP.(1-6) CLINICAL EFFECTS: The concurrent use of PDE inhibitors and vericiguat potentiates the hypotensive effects of both agents, which may result in dizziness, syncope, heart attack, or stroke.(1) PREDISPOSING FACTORS: Plasma levels of the PDE type-5 inhibitors may be higher in the following patients: those older than 65, with hepatic impairment, or with severe renal impairment. This may increase the severity of the interaction. PATIENT MANAGEMENT: The manufacturer of vericiguat states that administration of vericiguat to patients receiving PDE inhibitors, including specific PDE-5 inhibitors (avanafil,(2) sildenafil,(3) tadalafil,(4,5) or vardenafil(6)) and nonspecific PDE inhibitors (aminophylline, dipyridamole, theophylline) is not recommended.(1) The manufacturers of the PDE-5 inhibitors state that concurrent use of guanylate cyclase stimulators is contraindicated.(2-6) DISCUSSION: Concomitant use of vericiguat 10 mg with single doses of sildenafil (25, 50, or 100 mg) was associated with additional seated BP reduction of up to 5.4 mm Hg (systolic/diastolic BP, MAP), compared to administration of vericiguat alone.(1)	VERQUVO
Abrocitinib/Antiplatelets; Aspirin (Greater Than 100 mg) SEVERITY LEVEL: 2-Severe Interaction: Action is required to reduce the risk of severe adverse interaction. MECHANISM OF ACTION: Abrocitinib has been associated with transient, dose-dependent thrombocytopenia. The nadir platelet count occurs at a median of 24 days after receiving abrocitinib 200 mg once daily and a 40% recovery occurs by 12 weeks. Concurrent use with agents that affect platelet aggregation may result in an additive risk of bleeding.(1) CLINICAL EFFECTS: Concurrent use of abrocitinib with antiplatelet agents may increase the risk of bleeding.(1) PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. pre-existing thrombocytopenia). Abrocitinib is not recommended for patients with a platelet count less than 150,000/mm3.(1) Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding. PATIENT MANAGEMENT: The concurrent use of abrocitinib with antiplatelet agents (except aspirin < or = 81 mg daily) is contraindicated during the first 3 months of abrocitinib therapy. Prior to starting abrocitinib therapy, obtain a complete blood count and recheck at 4 weeks after initiation and 4 weeks after a dose increase. Discontinuation of abrocitinib is required if platelets drop below 50,000/mm3.(1) If concurrent therapy is warranted after the first 3 months of abrocitinib therapy, 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. 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: Abrocitinib has been associated with transient, dose-dependent thrombocytopenia and is more severe with lower baseline platelet counts. At baseline platelet counts of 170,000/mm3, 220,000/m3 and 270,000/mm3, the nadirs were -41.2%, -33.4%, and -26.5%, respectively. Recovery of platelet count (about 40% recovery by 12 weeks) occurred without discontinuation of the treatment.(1)	CIBINQO

There are 9 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
Platelet Aggregation Inhibitors/Selected Anticoagulants (Vitamin K antagonists); Heparins SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Platelet aggregation inhibitors work by irreversibly modifying the platelet ADP receptor and inhibiting the activation of GP IIb/IIIa complex.(1) Concurrent use with anticoagulants may result in additive effects on the clotting cascade. CLINICAL EFFECTS: The concurrent use of platelet aggregation inhibitors and anticoagulants may result in an increased risk of bleeding. PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Use caution when administering platelet aggregation inhibitors concurrently with anticoagulants.(1) Careful monitoring of appropriate laboratory values for the patient's anticoagulant (e.g. PTT for heparin, anti Xa levels for low-molecular weight heparins, INR for warfarin) as well as signs and symptoms of bleeding is warranted. 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. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. The time of highest risk for a coumarin-type drug interaction is when the precipitant drug is initiated or discontinued. Contact the prescriber before initiating, altering the dose or discontinuing either drug. DISCUSSION: Although a study in patients on long-term warfarin therapy found that the stable anticoagulation status was unaffected by concurrent clopidogrel use,(2) careful monitoring would be prudent. A self-controlled case study of 1,622 oral anticoagulant-precipitant drug pairs were reviewed and found 14% of drug pairs were associated with a statistically significant elevated risk of thromboembolism. Concurrent use of warfarin and dipyridamole resulted in a ratio of rate ratios (95% CI) of 2.07 (1.65-2.6); and warfarin and clopidogrel ratio of rate ratios 1.69 (1.56-1.84). A large systematic review was performed on 72 warfarin drug-drug interactions studies that reported on bleeding, thromboembolic events, or death. Most studies were retrospective cohorts. A meta-analysis of 38 of those studies found a higher rate of clinically significant bleeding in patients on warfarin and antiplatelets (OR=1.74; 95% CI 1.56-1.94). Increased bleeding risk was also seen in subgroup analyses with aspirin (OR=1.50; 95% CI 1.29-1.74), clopidogrel (OR=3.55; 95% CI 2.78-4.54), and aspirin plus clopidogrel or ticlopidine (OR=2.07, 95% CI 1.33-3.21).(4)	ACD-A, ACTIVASE, ANISINDIONE, ARIXTRA, CATHFLO ACTIVASE, CITRATE PHOSPHATE DEXTROSE, DICUMAROL, ELMIRON, ENOXAPARIN SODIUM, ENOXILUV, FONDAPARINUX SODIUM, FRAGMIN, HEPARIN SODIUM, HEPARIN SODIUM IN 0.45% NACL, HEPARIN SODIUM-0.45% NACL, HEPARIN SODIUM-0.9% NACL, HEPARIN SODIUM-D5W, JANTOVEN, LOVENOX, PENTOSAN POLYSULFATE SODIUM, PHENINDIONE, TNKASE, WARFARIN SODIUM
Eptifibatide/Platelet Aggregation Inhibitors SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Eptifibatide reversibly inhibits platelet aggregation by preventing the binding of fibrinogen, von Willebrand factor, and other adhesive ligands to GP IIb/IIIa.(1) Platelet aggregation inhibitors, such as clopidogrel, inhibit aggregation by inhibiting the binding of ADP to its platelet receptor.(2) CLINICAL EFFECTS: Concurrent use of eptifibatide and platelet aggregation inhibitors may cause additive effects and increase the risk of bleeding.(1) PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: The manufacturer of eptifibatide recommends employing caution when using eptifibatide with other drugs that affect hemostasis, such as eptifibatide.(1) 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. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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: The ESPRIT study observed the use of eptifibatide and clopidogrel or ticlopidine and found that when patients were carefully monitored there was no increase in risk of bleeding;(1) however, caution is still warranted.	EPTIFIBATIDE
SSRIs;SNRIs/Slt Anticoagulants;Antiplatelets;Thrombolytics SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Serotonin release by platelets plays a role in hemostasis.(1,2) The increased risk of bleeding may be a result of a decrease in serotonin reuptake by platelets. CLINICAL EFFECTS: Concurrent use of a selective serotonin reuptake inhibitor(1-6) or a serotonin-norepinephrine reuptake inhibitor(7-9) and agents that affect coagulation may result in bleeding. PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Renal impairment has been associated with an elevated risk of GI bleed in patients on SSRIs.(15) Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Selective serotonin reuptake inhibitors(1-6) or serotonin-norepinephrine reuptake inhibitors(7-9) and agents that affect coagulation should be used concurrently with caution. 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. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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 a retrospective review of 5 years of data from the Pharmaco-Epidemiologic Prescription Database, hospitalizations for upper gastro-intestinal bleeding in antidepressant users were compared to those in non-antidepressant users. The risk of a bleed in a patient using an NSAID only based on an observed-expected ration was 4.5 and in a patient using low-dose aspirin only was 2.5. Concurrent use of a selective serotonin reuptake inhibitor with NSAIDs or low-dose aspirin increased the risk of bleeding to 12.2 and 5.2, respectively.(10) In another study, there were 16 cases of upper gastrointestinal bleeding in patients receiving concurrent therapy with selective serotonin reuptake inhibitors and NSAIDs. Adjusted relative risk of bleeding with NSAIDs, selective serotonin reuptake inhibitors, or both were 3.7, 2.6, or 15.6, respectively.(11) In a case-control study conducted in users of acenocoumarol or phenprocoumon, 1848 patients who had been hospitalized with abnormal bleeding were each matched to 4 control patients. When patients took both a SSRI and a coumarin, an increased risk of hospitalization due to major non-gastrointestinal bleeding was observed (adjusted OR 1.7), but not due to gastrointestinal bleeding (adjusted OR 0.8).(12) A retrospective review examined patients discharged from a hospital with antiplatelet therapy following a myocardial infarction. When compared to aspirin therapy alone, both aspirin therapy with a SSRI and aspirin, clopidogrel, and SSRI therapy were associated with an increased risk of bleeding (hazard ratios 1.42 and 2.35, respectively.) Compared with dual antiplatelet therapy (aspirin and clopidogrel), use of aspirin and clopidogrel and a SSRI was also associated with increased risk of bleeding (hazard ratio 1.57).(13) In The Rotterdam Study, fluvoxamine increased the risk of over anticoagulation (hazard ratio 2.63). Paroxetine was not associated with an increased risk. There were insufficient numbers of patients taking other SSRIs to assess increased risk.(14) A self-controlled case study of 1,622 oral anticoagulant-precipitant drug pairs were reviewed and found 14% of drug pairs were associated with a statistically significant elevated risk of thromboembolism. Concurrent use of dabigatran and citalopram resulted in a ratio of rate ratios (95% CI) of 1.69 (1.11-2.57).(16) A systematic review and meta-analysis of 22 cohort and case-controlled studies including over 1 million patients found 1.55-fold higher odds of upper gastrointestinal (GI) bleeding in SSRI users compared with non-SSRI users (95% CI, 1.35-1.78). In subgroup analyses, the risk was found to be greatest among participants taking SSRIs concurrently with NSAIDs or antiplatelet medications.(17)	CELEXA, CITALOPRAM HBR, CYMBALTA, DESVENLAFAXINE ER, DESVENLAFAXINE SUCCINATE ER, DRIZALMA SPRINKLE, DULOXETINE HCL, DULOXICAINE, EFFEXOR XR, ESCITALOPRAM OXALATE, FETZIMA, FLUOXETINE DR, FLUOXETINE HCL, LEXAPRO, OLANZAPINE-FLUOXETINE HCL, PAROXETINE CR, PAROXETINE ER, PAROXETINE HCL, PAROXETINE MESYLATE, PAXIL, PAXIL CR, PRISTIQ, PROZAC, SAVELLA, SERTRALINE HCL, TRINTELLIX, VENLAFAXINE BESYLATE ER, VENLAFAXINE HCL, VENLAFAXINE HCL ER, VIIBRYD, VILAZODONE HCL, ZOLOFT
Mifepristone (Cushing)/Anticoagulants; Antiplatelets SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Mifepristone is an antagonist at the progesterone receptor which can result in endometrium thickening, cystic dilatation of endometrial glands, or excessive vaginal bleeding. Concurrent use with anticoagulants or antiplatelets may further increase risk. CLINICAL EFFECTS: The concurrent use of mifepristone with anticoagulants or antiplatelets may result in endometrium thickening, cystic dilatation of endometrial glands, or excessive vaginal bleeding. PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: The manufacturer of mifepristone states that mifepristone should be used with caution in patients receiving concurrent anticoagulant or antiplatelet therapy.(1) If concurrent therapy is deemed medically necessary, 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. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. Women experiencing vaginal bleeding during concurrent use should be referred to a gynecologist for further evaluation. DISCUSSION: The manufacturer of mifepristone states that mifepristone should be used with caution in patients receiving concurrent anticoagulant or antiplatelet therapy.(1)	KORLYM, MIFEPRISTONE
Icosapent Ethyl/Anticoagulant;Antiplatelet;Thrombolytic SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: In vitro data suggests that fish oils can competitively inhibit cyclooxygenase which decreases synthesis of thromboxane A1 leading to a decrease in platelet aggregation.(1) CLINICAL EFFECTS: Concurrent use of anticoagulant, antiplatelet, or thrombolytic agents increase bleeding risks. PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: If concurrent therapy is deemed medically necessary, 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. When applicable, perform agent-specific laboratory tests (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. The time of highest risk for a coumarin-type drug interaction is when the precipitant drug is initiated or discontinued. Contact the prescriber before initiating, altering the dose or discontinuing either drug. DISCUSSION: Specific studies with icosapent ethyl and affects on bleeding risk have not been conducted. Concurrent use of anticoagulant, antiplatelet, or thrombolytic agents may increase bleeding risks by impairing platelet function and prolonging bleeding time.(1) Several case reports have shown increased bleeding time and an increased risk of adverse effects from concurrent therapy.(2,3,4) A randomized placebo controlled study of 40 people taking omega-3 fatty acids and oral anticoagulants showed a significant prolongation in bleeding time.(5)	ICOSAPENT ETHYL, VASCEPA
Slt Anticoagulants;Antiplatelets;Thrombolytics/Fluvoxamine SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Serotonin release by platelets plays a role in hemostasis.(1) Fluvoxamine may cause a decrease in serotonin reuptake by platelets, resulting in an additive risk of bleeding with anticoagulants, antiplatelets, and thrombolytics. CLINICAL EFFECTS: Concurrent use of fluvoxamine and agents that affect coagulation may result in bleeding. PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Renal impairment has been associated with an elevated risk of GI bleed in patients on SSRIs.(2) Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Concurrent therapy of fluvoxamine and agents that affect coagulation should be undertaken with caution. 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. When applicable, perform agent-specific laboratory test (e.g. INR, aPTT, anti Factor Xa inhibition) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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 a retrospective review of 5 years of data from the Pharmaco-Epidemiologic Prescription Database, hospitalizations for upper gastro-intestinal bleeding in antidepressant users were compared to those in non-antidepressant users. The risk of a bleed in a patient using an NSAID only based on an observed-expected ration was 4.5 and in a patient using low-dose aspirin only was 2.5. Concurrent use of a selective serotonin reuptake inhibitor with NSAIDs or low-dose aspirin increased the risk of bleeding to 12.2 and 5.2, respectively.(3) In another study, there were 16 cases of upper gastrointestinal bleeding in patients receiving concurrent therapy with selective serotonin reuptake inhibitors and NSAIDs. Adjusted relative risk of bleeding with NSAIDs, selective serotonin reuptake inhibitors, or both were 3.7, 2.6, or 15.6, respectively.(4) In a case-control study conducted in users of acenocoumarol or phenprocoumon, 1,848 patients who had been hospitalized with abnormal bleeding were each matched to 4 control patients. When patients took both a SSRI and a coumarin, an increased risk of hospitalization due to major non-gastrointestinal bleeding was observed (adjusted OR 1.7), but not due to gastrointestinal bleeding (adjusted OR 0.8).(5) A retrospective review examined patients discharged from a hospital with antiplatelet therapy following a myocardial infarction. When compared to aspirin therapy alone, both aspirin therapy with a SSRI and aspirin, clopidogrel, and SSRI therapy were associated with an increased risk of bleeding (hazard ratios 1.42 and 2.35, respectively.) Compared with dual antiplatelet therapy (aspirin and clopidogrel), use of aspirin and clopidogrel and a SSRI was also associated with increased risk of bleeding (hazard ratio 1.57).(6) In The Rotterdam Study, fluvoxamine increased the risk of over anticoagulation (hazard ratio 2.63). Paroxetine was not associated with an increased risk. There were insufficient numbers of patients taking other SSRIs to assess increased risk.(7) A self-controlled case study of 1,622 oral anticoagulant-precipitant drug pairs were reviewed and found 14% of drug pairs were associated with a statistically significant elevated risk of thromboembolism. Concurrent use of dabigatran and citalopram resulted in a ratio of rate ratios (95% CI) of 1.69 (1.11-2.57).(8)	FLUVOXAMINE MALEATE, FLUVOXAMINE MALEATE ER
Tisotumab/Anticoagulants; Antiplatelets SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Bleeding, including hemorrhage, has been reported with the use of tisotumab.(1) CLINICAL EFFECTS: Concurrent use of tisotumab with either anticoagulants, antiplatelets, or NSAIDs may increase the risk of hemorrhage.(1) PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Patients receiving concurrent therapy with tisotumab and anticoagulants, antiplatelets, and/or NSAIDs should be closely monitored for signs and symptoms of bleeding and changes in platelet count or International Normalized Ratio (INR). For patients experiencing pulmonary or central nervous system (CNS) hemorrhage, permanently discontinue tisotumab. For grade 2 or greater hemorrhage in any other location, withhold until bleeding has resolved, blood hemoglobin is stable, there is no bleeding diathesis that could increase the risk of continuing therapy, and there is no anatomical or pathologic condition that can increase the risk of hemorrhage. After resolution, either resume treatment or permanently discontinue tisotumab.(1) 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. When applicable, perform agent-specific laboratory tests (e.g. INR, aPTT) to monitor efficacy and safety of anticoagulation. Discontinue anticoagulation in patients with active pathologic 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. The time of highest risk for a coumarin-type drug interaction is when the precipitant drug is initiated or discontinued. Contact the prescriber before initiating, altering the dose or discontinuing either drug. DISCUSSION: Hemorrhage occurred in 62% of patients with cervical cancer treated with tisotumab across clinical trials. The most common all grade hemorrhage adverse reactions were epistaxis (44%), hematuria (10%), and vaginal hemorrhage (10%). Grade 3 hemorrhage occurred in 5% of patients.(1)	TIVDAK
Lecanemab/Antiplatelets SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Microhemorrhage has been reported with the use of lecanemab. Radiographic changes on brain MRI have been noted as amyloid related imaging abnormalities-hemosiderin deposition (ARIA-H) which included microhemorrhage. In addition, intracerebral hemorrhages (ICH) greater than 1 cm in diameter have occurred in patients treated with lecanemab.(1) CLINICAL EFFECTS: Concurrent use of lecanemab with antiplatelets may increase the risk of hemorrhage.(1) PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Lecanemab should be used with extreme caution in patients treated with antiplatelets. Evaluate the risks and benefits of concurrent use of lecanemab with antiplatelets.(1) Appropriate use recommendations for lecanemab state antiplatelets may be used at standard doses if patients meet other criteria for lecanemab therapy. Use of antiplatelet agents in patients who are homozygous for the APOE4 gene may have an increased risk of ARIA with lecanemab therapy.(2) Patients receiving concurrent therapy with lecanemab and antiplatelets should be closely monitored for signs and symptoms of bleeding and changes in platelet count or International Normalized Ratio (INR).(1) If concurrent therapy is warranted, monitor patients receiving concurrent therapy for signs of microhemorrhage, including headache, nausea/vomiting, confusion, dizziness, visual disturbance, gait difficulties, and loss of coordination. General signs of blood loss include decreased hemoglobin, hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. Instruct patients to report any signs and symptoms of bleeding, such as confusion, headache, dizziness, nausea, visual changes, 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 studies, lecanemab was observed to increase ARIA-H, including microhemorrhage and intracerebral hemorrhage. Radiographic changes were classified as mild (<=4 new incidences), moderate (5 to 9 new incidences), or severe (10 or more new incidences. Patients were excluded from clinical trials if taking concurrent anticoagulants or anti-platelets.(1) In Studies 1 and 2, the maximum severity of ARIA-H microhemorrhage was mild in 9% (79/898), moderate in 2% (19/898), and severe in 3% (28/898) of patients. Intracerebral hemorrhage greater than 1 cm in diameter was reported in 0.7% (6/898) of patients in Study 2 after treatment with lecanemab compared to 0.1% (1/897) on placebo. Fatal events of intracerebral hemorrhage in patients taking lecanemab have been observed.(1) In Study 2, baseline use of antithrombotic medications (aspirin, other antiplatelets, or anticoagulants) were allowed if patient was on a stable dose. Aspirin was the most common antithrombotic agent. The incidence of ICH was 0.9% (3/328 patients) in patients taking lecanemab with a concomitant antithrombotic medication at the time of the event compared to 0.6% (3/545 patients) in those who did not receive an antithrombotic. Patients taking lecanemab with an anticoagulant alone or combined with an antiplatelet medication or aspirin had an incidence of intracerebral hemorrhage of 2.5% (2/79 patients) compared to none in patients who received placebo.	LEQEMBI
Donanemab/Antiplatelets SEVERITY LEVEL: 3-Moderate Interaction: Assess the risk to the patient and take action as needed. MECHANISM OF ACTION: Microhemorrhage has been reported with the use of donanemab. Radiographic changes on brain MRI have been noted as amyloid related imaging abnormalities-hemosiderin deposition (ARIA-H) which included microhemorrhage. In addition, intracerebral hemorrhages (ICH) greater than 1 cm in diameter have occurred in patients treated with donanemab.(1) CLINICAL EFFECTS: Concurrent use of donanemab with antiplatelets may increase the risk of hemorrhage.(1) PREDISPOSING FACTORS: The risk for bleeding episodes may be greater in patients with disease-associated factors (e.g. thrombocytopenia). Drug associated risk factors include concurrent use of multiple drugs which inhibit anticoagulant/antiplatelet metabolism and/or have an inherent risk for bleeding (e.g. NSAIDs). PATIENT MANAGEMENT: Donanemab should be used with extreme caution in patients treated with antiplatelets. Evaluate the risks and benefits of concurrent use of donanemab with antiplatelets.(1) The manufacturer of donanemab recommends testing for AP0E4 status prior to initiation of treatment.(1) Use of antiplatelet agents in patients who are homozygous for the APOE4 gene, may have an increased risk of ARIA with donanemab therapy.(1-3) Patients receiving concurrent therapy with donanemab and antiplatelets should be closely monitored for signs and symptoms of bleeding and changes in platelet count.(1) If concurrent therapy is warranted, monitor patients receiving concurrent therapy for signs of microhemorrhage, including headache, nausea/vomiting, confusion, dizziness, visual disturbance, gait difficulties, and loss of coordination. General signs of blood loss include decreased hemoglobin, hematocrit, fecal occult blood, and/or decreased blood pressure and promptly evaluate patients with any symptoms. Instruct patients to report any signs and symptoms of bleeding, such as confusion, headache, dizziness, nausea, visual changes, 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 a double-blind, placebo-controlled clinical study of 1736 participants randomized to receive donanemab (n = 860) or placebo (n = 876), donanemab was observed to increase amyloid related imaging abnormalities-hemosiderin deposition (ARIA-H), including microhemorrhage and intracerebral hemorrhage (ICH). Radiographic changes were classified as mild (<=4 new incidences), moderate (5 to 9 new incidences), or severe (10 or more new incidences). The maximum severity of ARIA-H microhemorrhage was observed as mild in 17% (143/853), moderate in 4% (34/853), and severe in 5% (40/853) of patients taking donanemab.(1) Baseline use of antithrombotic medications (aspirin, other antiplatelets, or anticoagulants) was allowed. The majority of exposures to antithrombotic medications were to aspirin. The incidence of ARIA-H was 30% (106/349) in patients taking donanemab with a concomitant antithrombotic medication within 30 days compared to 29% (148/504) who did not receive an antithrombotic within 30 days of an ARIA-H event.(1) The incidence of ICH greater than 1 cm in diameter was 0.6% (2/349 patients) in patients taking donanemab with a concomitant antithrombotic medication compared to 0.4% (2/504) in those who did not receive an antithrombotic. One fatal ICH occurred in a patient taking donanemab in the setting of focal neurologic symptoms of ARIA and the use of a thrombolytic agent.(1)	KISUNLA

The following contraindication information is available for DIPYRIDAMOLE (dipyridamole):

Overview
Contraindicated
Severe
Moderate

Drug contraindication overview.

No enhanced Contraindications information available for this drug.

There are 5 contraindications. Absolute contraindication.

Contraindication List
Cerebral amyloid angiopathy
Deep peripheral nerve block
Deep plexus block
Intracranial bleeding
Neuraxial anesthesia

There are 0 severe contraindications.

There are 3 moderate contraindications. Clinically significant contraindication, where the condition can be managed or treated before the drug may be given safely.

Moderate List
Disease of liver
Hypotension
Unstable angina pectoris

The following adverse reaction information is available for DIPYRIDAMOLE (dipyridamole):

Overview
Severe
Less Severe

Adverse reaction overview.

No enhanced Common Adverse Effects information available for this drug.

There are 23 severe adverse reactions.

More Frequent	Less Frequent
Angina Extrasystoles Hypertension Hypotension ST segment changes Tachycardia	Allergic dermatitis Dyspnea Urticaria

Rare/Very Rare
Abnormal ECG Acute myocardial infarction Bronchospastic pulmonary disease Cardiac arrhythmia Cardiomyopathy Cerebral ischemia Edema Hypertonia Hyperventilation Hypoesthesia Intermittent claudication Migraine Orthostatic hypotension Ventricular fibrillation

There are 19 less severe adverse reactions.

More Frequent	Less Frequent
Abdominal pain with cramps Diarrhea Dizziness Gastrointestinal irritation Headache disorder Nausea Vomiting	Flushing General weakness Pruritus of skin Skin rash

Rare/Very Rare
Back pain Chest pain Cramps in legs Depersonalization Dysgeusia Ocular pain Pleuritis Rhinitis

The following precautions are available for DIPYRIDAMOLE (dipyridamole):

Pediatric
Pregnant
Lactation
Geriatric

No enhanced Pediatric Use information available for this drug.

Contraindicated

None

Severe Precaution

None

Management or Monitoring Precaution

None

Safe use of dipyridamole during pregnancy has not been established. Reproduction studies in mice receiving dipyridamole dosages up to 125 mg/kg daily (1.5 times the maximum recommended daily human oral dosage on a mg/m2 basis), rats receiving dosages not exceeding 1000 mg/kg daily (25 times the maximum recommended daily human oral dosage on a mg/m2 basis), and rabbits receiving dosages not exceeding 40 mg/kg daily (2 times the maximum recommended daily human oral dosage on a mg/m2 basis) have not revealed evidence of harm to the fetus. There are no adequate and controlled studies to date using dipyridamole in pregnant women, and the drug should be used during pregnancy only when clearly needed.

Extended-release dipyridamole in fixed combination with aspirin should be avoided in the third trimester of pregnancy and during labor and delivery because of the aspirin component of this preparation; aspirin has been shown to be teratogenic in animals and to cause fetal harm when administered to a pregnant woman. If dipyridamole in fixed combination with aspirin is used during pregnancy or the patient becomes pregnant while taking the fixed combination, the patient should be apprised of the potential hazard to the fetus. (See Cautions: Pregnancy, Fertility, and Lactation, in the Salicylates General Statement 28:08.04.24.)

Because dipyridamole is distributed into milk, the drug should be used with caution in nursing women.

No enhanced Geriatric Use information available for this drug.