Heparin interactions

Heparin (Hep-Lock), an anticoagulant has 251 documented interactions across the FDA labels and fact sheets we index: 19 major, 175 moderate, 53 minor, and 4 where a label reports no significant interaction. Each entry below quotes the sentence behind it. This drug page is a starting point, not a verdict for your situation.

Interactions from the label

Major interactions (19)

  • Aminocaproic acidantifibrinolyticMajor

    Aminocaproic acid must not be used in the presence of DIC without concomitant heparin. (Aminocaproic acid label, Contraindications)

  • AmiodaroneantiarrhythmicMajor

    Warfarin Potentiates anticoagulant response and can result in serious or fatal bleeding. (Amiodarone label, Drug interactions)

  • ApixabananticoagulantMajor

    Avoid use of heparin after use of andexanet alfa for the reversal of direct Factor Xa inhibitors (apixaban and rivaroxaban). (Heparin label, Drug interactions)

  • AtazanavirantiretroviralMajor

    Anticoagulants: warfarin ↑ warfarin Coadministration with REYATAZ has the potential to produce serious and/or life-threatening bleeding and has not been studied. (Atazanavir label, Drug interactions)

  • BivalirudinanticoagulantMajor

    Among patients who experienced an AST, one fatality (0.03%) occurred in a bivalirudin treated patient and one fatality (0.03%) in a heparin treated patient. (Bivalirudin label, Warnings and precautions)

  • DabigatrananticoagulantMajor

    To reduce this risk, consider coverage with another anticoagulant if PRADAXA is discontinued for a reason other than pathological bleeding or completion of a course of therapy ( 2.6 , 2.7 , 2.8 , 5.1 ). (Dabigatran label, Boxed warning)

  • EdoxabananticoagulantMajor

    In these patients another anticoagulant should be used ( 5.1 ). (Edoxaban label, Boxed warning)

  • EfavirenzantiretroviralMajor

    …Voxilaprevir ↓ velpatasvir ↓ voxilaprevir Coadministration of efavirenz and sofosbuvir/velpatasvir/voxilaprevir is not recommended because it may result in loss of therapeutic effect of sofosbuvir/velpatasvir/voxilaprevir Other agents Anticoagulant:Warfarin ↑ or ↓ warfarin Monitor international normalised ratio (INR) and adjust warfarin dosage if necessary. (Efavirenz label, Drug interactions)

  • EnoxaparinanticoagulantMajor

    WARNING: SPINAL/EPIDURAL HEMATOMAS Epidural or spinal hematomas may occur in patients who are anticoagulated with low molecular weight heparins (LMWH) or heparinoids and are receiving neuraxial anesthesia or undergoing spinal puncture. (Enoxaparin label, Boxed warning)

  • Epoprostenolprostaglandin analogMajor

    Unless contraindicated, administer anticoagulant therapy to patients receiving VELETRI to reduce the risk of pulmonary thromboembolism or systemic embolism through a patent foramen ovale. (Epoprostenol label, Warnings and precautions)

  • FondaparinuxanticoagulantMajor

    WARNING: SPINAL/EPIDURAL HEMATOMAS Epidural or spinal hematomas may occur in patients who are anticoagulated with low molecular weight heparins (LMWH), heparinoids, or fondaparinux sodium and are receiving neuraxial anesthesia or undergoing spinal puncture. (Fondaparinux label, Boxed warning)

  • Itraconazoleazole antifungalMajor

    Anticoagulants and Antiplatelets Ticagrelor Contraindicated during and 2 weeks after TOLSURA treatment. (Itraconazole label, Drug interactions)

  • Prasugrelantiplatelet agentMajor

    Additional risk factors for bleeding include: body weight <60 kg, propensity to bleed, concomitant use of medications that increase the risk of bleeding (e.g . , warfarin, heparin, fibrinolytic therapy, chronic use of nonsteroidal anti-inflammatory drugs [NSAIDs]) [see Warnings and Precautions (5.1) ] . (Prasugrel label, Boxed warning)

  • Protamine sulfate should not be given when bleeding occurs without prior heparin use. (Protamine label, Boxed warning)

  • RifampinantibioticMajor

    …Antipsychotics Haloperidol Decrease plasma concentrations by 70% Lurasidone Prevention or Management: Concomitant use is contraindicated (See CONTRAINDICATIONS ) Decrease exposure Oral Anticoagulants Prevention or Management: Perform prothrombin time daily or as frequently as necessary to establish and maintain the required dose of anticoagulant Warfarin Decrease… (Rifampin label, Drug interactions)

  • RitonavirantiretroviralMajor

    Anticoagulant: rivaroxaban ↑ rivaroxaban Avoid concomitant use of rivaroxaban and ritonavir. (Ritonavir label, Drug interactions)

  • RivaroxabananticoagulantMajor

    Avoid use of heparin after use of andexanet alfa for the reversal of direct Factor Xa inhibitors (apixaban and rivaroxaban). (Heparin label, Drug interactions)

  • Tamoxifenselective estrogen receptor modulatorMajor

    For women with DCIS and for the reduction in breast cancer incidence in women at high risk, tamoxifen is contraindicated in women who require concomitant warfarin-type anticoagulant therapy or in women with a history of deep vein thrombosis or pulmonary embolus. (Tamoxifen label, Warnings and precautions)

  • WarfarinanticoagulantMajor

    Heparin-induced thrombocytopenia (HIT): Initial therapy with warfarin sodium in HIT has resulted in cases of amputation and death. (Warfarin label, Warnings and precautions)

Moderate interactions (175)

  • Chronic oral acetaminophen use at a dose of 4,000 mg/day has been shown to cause an increase in international normalized ratio (INR) in some patients who have been stabilized on sodium warfarin as an anticoagulant. (Acetaminophen label, Drug interactions)

  • Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Allopurinolxanthine oxidase inhibitorModerate

    Dicumarol Clinical Impact Allopurinol tablets prolongs the half-life of the anticoagulant, dicumarol. (Allopurinol label, Drug interactions)

  • Alprostadilprostaglandin analogModerate

    • Injection site bleeding may occur in patients taking anticoagulants, such as warfarin or heparin. (Alprostadil label, Warnings and precautions)

  • AlteplaseModerate

    Because heparin, aspirin, or Activase may cause bleeding complications, carefully monitor for bleeding, especially at arterial puncture sites. (Alteplase label, Warnings and precautions)

  • Amlodipine and valsartandihydropyridine calcium channel blockerModerate

    …other agents that block the renin-angiotensin system, potassium-sparing diuretics (e.g., spironolactone, triamterene, amiloride), potassium supplements, salt substitutes containing potassium or other drugs that may increase potassium levels (e.g., heparin) may lead to increases in serum potassium and in heart failure patients to increases in serum creatinine. (Amlodipine and valsartan label, Drug interactions)

  • Amoxicillinpenicillin antibioticModerate

    Concomitant use of amoxicillin and oral anticoagulants may increase the prolongation of prothrombin time. (Amoxicillin label, Drug interactions)

  • Amoxicillin and clavulanatepenicillin antibioticModerate

    Concomitant use Amoxicillin and Clavulanate Potassium Extended Release Tablets and oral anticoagulants may increase the prolongation of prothrombin time. (Amoxicillin and clavulanate label, Drug interactions)

  • AnagrelideQT-prolonging drugModerate

    Monitor patients for bleeding, including those receiving concomitant therapy with other drugs known to cause bleeding (e.g., anticoagulants, PDE3 inhibitors, NSAIDs, antiplatelet agents, selective serotonin reuptake inhibitors) [see Drug Interactions (7.3) , Clinical Pharmacology (12.3) ] . (Anagrelide label, Warnings and precautions)

  • ArgatrobananticoagulantModerate

    Heparin: Allow sufficient time for heparin’s effect on activated partial thromboplastin time (aPTT) to decrease before initiating Argatroban Injection therapy. (Argatroban label, Drug interactions)

  • AspirinNSAIDModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Aspirin and dipyridamoleantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Atovaquone and proguanilantimalarialModerate

    • Proguanil may potentiate anticoagulant effect of warfarin and other coumarin-based anticoagulants. (Atovaquone and proguanil label, Drug interactions)

  • Azithromycinmacrolide antibioticModerate

    Prothrombin times should be carefully monitored while patients are receiving azithromycin and oral anticoagulants concomitantly. (Azithromycin label, Drug interactions)

  • Betaxololbeta blockerModerate

    Concomitant administration of betaxolol with the oral anticoagulant warfarin has been shown not to potentiate the anticoagulant effect of warfarin. (Betaxolol label, Drug interactions)

  • BicalutamideandrogenModerate

    Closely monitor the Prothrombin Time (PT) and International Normalized Ratio (INR), and adjust the anticoagulant dose as needed. (Bicalutamide label, Warnings and precautions)

  • Metronidazole has been reported to potentiate the anticoagulant effect of warfarin, and other oral coumarin anticoagulants, resulting in a prolongation of prothrombin time. (Bismuth subcitrate, metronidazole, and tetracycline label, Warnings and precautions)

  • Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Cangrelorantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • CapecitabineantimetaboliteModerate

    Closely monitor for adverse reactions of CYP2C9 substrates where minimal concentration changes may lead to serious adverse reactions when used concomitantly with XELODA (e.g., anticoagulants, antidiabetic drugs). (Capecitabine label, Drug interactions)

  • CarbamazepineanticonvulsantModerate

    Warfarin (CYP1A2 and CYP3A4 Substrate) Through induction of CYP1A2 and CYP3A4, EQUETRO decreases the concentration of warfarin and decreases its anticoagulant effectiveness. (Carbamazepine label, Drug interactions)

  • CefazolincephalosporinModerate

    Those at risk include patients with renal or hepatic impairment or poor nutritional state, as well as patients receiving a protracted course of antimicrobial therapy, and patients previously stabilized on anticoagulant therapy. (Cefazolin label, Warnings and precautions)

  • CefiximecephalosporinModerate

    Those at risk include patients with renal or hepatic impairment, or poor nutritional state, as well as patients receiving a protracted course of antimicrobial therapy, and patients previously stabilized on anticoagulant therapy. (Cefixime label, Warnings and precautions)

  • CelecoxibNSAIDModerate

    Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, antiplatelet drugs (such as aspirin), anticoagulants; or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Celecoxib label, Warnings and precautions)

  • CephalexincephalosporinModerate

    Those at risk include patients with renal or hepatic impairment, or poor nutritional state, as well as patients receiving a protracted course of antibacterial therapy, and patients receiving anticoagulant therapy. (Cephalexin label, Warnings and precautions)

  • Cilostazolantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • CimetidineH2 blockerModerate

    Drug Interactions Cimetidine tablets, apparently through an effect on certain microsomal enzyme systems, has been reported to reduce the hepatic metabolism of warfarin-type anticoagulants, phenytoin, propranolol, nifedipine, chlordiazepoxide, diazepam, certain tricyclic antidepressants, lidocaine, theophylline, and metronidazole, thereby delaying elimination… (Cimetidine label, Drug interactions)

  • CiprofloxacinfluoroquinoloneModerate

    Anti-coagulant drugs Use with caution (Increase in anticoagulant effect) The risk may vary with the underlying infection, age and general status of the patient so that the contribution of ciprofloxacin to the increase in INR (international normalized ratio) is difficult to assess. (Ciprofloxacin label, Drug interactions)

  • CitalopramSSRIModerate

    Increased Risk of Bleeding: Concomitant use of aspirin, nonsteroidal anti-inflammatory drugs, other antiplatelet drugs, warfarin, and other anticoagulants may increase this risk. (Citalopram label, Warnings and precautions)

  • Clarithromycinmacrolide antibioticModerate

    Oral Anticoagulants: There is a risk of serious hemorrhage and significant elevations in INR and prothrombin time when clarithromycin is co-administered with warfarin. (Clarithromycin label, Warnings and precautions)

  • Clopidogrelantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • CyclophosphamideimmunosuppressantModerate

    Monitor anticoagulant activity closely in patients receiving warfarin or other coumarins. (Cyclophosphamide label, Drug interactions)

  • CyclosporineimmunosuppressantModerate

    Though resolution has occurred after reduction or discontinuation of cyclosporine and 1) administration of streptokinase and heparin or 2) plasmapheresis, this appears to depend upon early detection with Indium 111 labeled platelet scans (see ADVERSE REACTIONS) . (Cyclosporine label, Warnings)

  • DarunavirantiretroviralModerate

    Anticoagulants : Direct Oral Anticoagulants (DOACs) apixaban ↑ apixaban Due to potentially increased bleeding risk, dosing recommendations for co-administration of apixaban with PREZISTA/ritonavir depend on the apixaban dose. (Darunavir label, Drug interactions)

  • Darunavir and cobicistatantiretroviralModerate

    Anticoagulants: Direct Oral Anticoagulants (DOACs) apixaban ↑ apixaban Due to potentially increased bleeding risk, dosing recommendations for co-administration of apixaban with PREZCOBIX or PREZCOBIX PED depend on the apixaban dose. (Darunavir and cobicistat label, Drug interactions)

  • DasatinibModerate

    Use caution if used concomitantly with medications that inhibit platelet function or anticoagulants. (Dasatinib label, Warnings and precautions)

  • Deferasiroxiron supplementModerate

    The risk of GI hemorrhage may be increased when administering Exjade in combination with drugs that have ulcerogenic or hemorrhagic potential, such as nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, oral bisphosphonates, or anticoagulants. (Deferasirox label, Warnings and precautions)

  • Demeclocyclinetetracycline antibioticModerate

    Drug Interactions Because tetracyclines have been shown to depress plasma prothrombin activity, patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage. (Demeclocycline label, Drug interactions)

  • DesvenlafaxineSNRIModerate

    • Increased Risk of Bleeding: Concomitant use of aspirin, NSAIDs, other antiplatelet drugs, warfarin, and other anticoagulants may increase this risk ( 5.4 ). (Desvenlafaxine label, Warnings and precautions)

  • DexamethasonecorticosteroidModerate

    (‎ 5.3 ) • Venous and Arterial Thromboembolism: Risk increased; consider anticoagulant prophylaxis and monitor for evidence of thromboembolism. (Dexamethasone label, Warnings and precautions)

  • DiclofenacNSAIDModerate

    Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Diclofenac label, Warnings and precautions)

  • Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, antiplatelet drugs (such as aspirin), anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Diclofenac and misoprostol label, Warnings and precautions)

  • Dicloxacillinpenicillin antibioticModerate

    Dicloxacillin may reduce the anticoagulant response to dicumarol and warfarin. (Dicloxacillin label, Drug interactions)

  • DiflunisalNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include concomitant use of oral corticosteroids or anticoagulants, longer duration of NSAID therapy, smoking, use of alcohol, older age, and poor general health status. (Diflunisal label, Warnings)

  • Dipyridamoleantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • DisulfiramCYP2C9 inhibitorModerate

    It may be necessary to adjust the dosage of oral anticoagulants upon beginning or stopping disulfiram, since disulfiram may prolong prothrombin time. (Disulfiram label, Drug interactions)

  • Divalproex (valproate)anticonvulsantModerate

    The therapeutic relevance of this is unknown; however, coagulation tests should be monitored if valproate therapy is instituted in patients taking anticoagulants. (Divalproex (valproate) label, Drug interactions)

  • DofetilideantiarrhythmicModerate

    Concomitant medications were grouped as ACE inhibitors, oral anticoagulants, calcium channel blockers, beta blockers, cardiac glycosides, inducers of CYP3A4, substrates and inhibitors of CYP3A4, substrates and inhibitors of P-glycoprotein, nitrates, sulphonylureas, loop diuretics, potassium sparing diuretics, thiazide diuretics, substrates and inhibitors of tubular… (Dofetilide label, Drug interactions)

  • Doxycyclinetetracycline antibioticModerate

    Patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage. (Doxycycline label, Drug interactions)

  • Drospirenone and ethinyl estradioloral contraceptiveModerate

    Medications that may increase serum potassium concentration include ACE inhibitors, angiotensin-II receptor antagonists, potassium-sparing diuretics, potassium supplementation, heparin, aldosterone antagonists, and NSAIDS. (Drospirenone and ethinyl estradiol label, Warnings and precautions)

  • DuloxetineSNRIModerate

    Concomitant use of antiplatelet drugs and anticoagulants may increase this risk. (Duloxetine label, Warnings and precautions)

  • Econazoleazole antifungalModerate

    - 7.1 Warfarin Concomitant administration of econazole and warfarin has resulted in enhancement of anticoagulant effect. (Econazole label, Drug interactions)

  • Concomitant Drug Class: Drug Name Effect Clinical Comment Anticoagulant: Warfarin ↑ or ↓ warfarin Monitor INR and adjust warfarin dosage if necessary. (Efavirenz, lamivudine, and tenofovir label, Drug interactions)

  • Anticoagulants: Direct Oral Anticoagulants (DOACs) apixaban rivaroxaban betrixaban dabigatran edoxaban ↑ apixaban Due to potentially increased bleeding risk, dosing recommendations for coadministration with GENVOYA depends on the apixaban dose. (Elvitegravir, cobicistat, emtricitabine, and tenofovir label, Drug interactions)

  • Epoetin alfaModerate

    Patients receiving Epogen may require increased anticoagulation with heparin to prevent clotting of the extracorporeal circuit during hemodialysis. (Epoetin alfa label, Warnings and precautions)

  • Eptifibatideantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • ErlotinibModerate

    • Hemorrhage in patients taking warfarin: Regularly monitor INR in patients taking warfarin or other coumarin-derivative anticoagulants. (Erlotinib label, Warnings and precautions)

  • Erythromycinmacrolide antibioticModerate

    There have been reports of increased anticoagulant effects when erythromycin and oral anticoagulants were used concomitantly. (Erythromycin label, Drug interactions)

  • EscitalopramSSRIModerate

    Increased Risk of Bleeding: Concomitant use of nonsteroidal anti-inflammatory drugs, aspirin, other antiplatelet drugs, warfarin and other anticoagulants may increase risk ( 5.7 , 7) (Escitalopram label, Warnings and precautions)

  • Drug Interactions (Androgens) Anticoagulants: C-17 substituted derivatives of testosterone, such as methandrostenolone, have been reported to decrease the anticoagulant requirements of patients receiving oral anticoagulants. (Esterified estrogens and methyltestosterone label, Drug interactions)

  • Ethacrynic acidloop diureticModerate

    A number of drugs, including ethacrynic acid, have been shown to displace warfarin from plasma protein; a reduction in the usual anticoagulant dosage may be required in patients receiving both drugs. (Ethacrynic acid label, Drug interactions)

  • EtodolacNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include concomitant use of oral corticosteroids or anticoagulants, longer duration of NSAID therapy, smoking, use of alcohol, older age, and poor general health status. (Etodolac label, Warnings)

  • EtravirineantiretroviralModerate

    Anticoagulant : warfarin ↑ anticoagulants Warfarin concentrations may be increased when co-administered with Etravirine. (Etravirine label, Drug interactions)

  • Coumarin Anticoagulants: Obtain INR before VYTORIN initiation and monitor INR during VYTORIN dosage initiation or adjustment. (Ezetimibe and simvastatin label, Drug interactions)

  • FenofibratefibrateModerate

    Increased Bleeding Risk with Coumarin Anticoagulants Exercise caution when co-administering anticoagulants with fenofibrate capsules because of the potentiation of coumarin-type anticoagulant effects in prolonging the prothrombin time/International Normalized Ratio (PT/INR). (Fenofibrate label, Warnings and precautions)

  • Fenofibric acidfibrateModerate

    Increased Bleeding Risk with Coumarin Anticoagulants Exercise caution when co-administering anticoagulants with fenofibric acid delayed-release capsules because of the potentiation of coumarin-type anticoagulant effects in prolonging the prothrombin time/International Normalized Ratio (PT/INR). (Fenofibric acid label, Warnings and precautions)

  • FenoprofenNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Fenoprofen label, Warnings and precautions)

  • Fluconazoleazole antifungalModerate

    Coumarin-type anticoagulants Prothrombin time may be increased in patients receiving concomitant fluconazole and coumarin-type anticoagulants. (Fluconazole label, Drug interactions)

  • FludrocortisonecorticosteroidModerate

    Oral anticoagulants — decreased prothrombin time response. (Fludrocortisone label, Drug interactions)

  • FluorouracilantimetaboliteModerate

    Closely monitor patients receiving concomitant coumarin-derivative anticoagulants such as warfarin for INR or prothrombin time in order to adjust the anticoagulant dose accordingly [see Drug Interactions (7) ]. (Fluorouracil label, Warnings and precautions)

  • FluoxetineSSRIModerate

    Altered anticoagulant effects, including increased bleeding, have been reported when SNRIs or SSRIs are coadministered with warfarin. (Fluoxetine label, Drug interactions)

  • FlurbiprofenNSAIDModerate

    Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking, use of alcohol, older age, and poor general health status. (Flurbiprofen label, Warnings and precautions)

  • FlutamideandrogenModerate

    Therefore close monitoring of prothrombin time is recommended and adjustment of the anticoagulant dose may be necessary when Eulexin ® capsules are administered concomitantly with warfarin. (Flutamide label, Drug interactions)

  • FluvoxamineSSRIModerate

    Thus patients receiving oral anticoagulants and Fluvoxamine Maleate Tablets should have their prothrombin time monitored and their anticoagulant dose adjusted accordingly. (Fluvoxamine label, Warnings and precautions)

  • FosphenytoinanticonvulsantModerate

    …Corticosteroids, doxycycline, estrogens, furosemide, oral contraceptives, paroxetine, quinidine, rifampin, sertraline, theophylline, and vitamin D Drugs whose level is decreased by phenytoin Anticoagulants Apixaban, dabigatran, edoxaban, rivaroxaban Antiepileptic drugs The effect of phenytoin on phenobarbital, valproic acid and sodium valproate serum levels is unpredictable. (Fosphenytoin label, Drug interactions)

  • FulvestrantestrogenModerate

    Risk of Bleeding: Use with caution in patients with bleeding diatheses, thrombocytopenia, or anticoagulant use. (Fulvestrant label, Warnings and precautions)

  • GemfibrozilfibrateModerate

    Concomitant Anticoagulants – Caution should be exercised when warfarin is given in conjunction with LOPID. (Gemfibrozil label, Warnings)

  • Ginkgo bilobaHerbal and supplementModerate

    Ginkgo may increase bleeding risk when taken with anticoagulant or antiplatelet medicines. (NCCIH, Ginkgo)

  • GlucagonModerate

    Warfarin Clincial Impact: GVOKE and GVOKE Vial Dx may increase the anticoagulant effect of warfarin. (Glucagon label, Drug interactions)

  • GriseofulvinantifungalModerate

    Griseofulvin decreases the activity of warfarin-type anticoagulants, so that patients receiving these drugs concomitantly may require dosage adjustment of the anticoagulant during and after griseofulvin therapy. (Griseofulvin label, Drug interactions)

  • Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • HydrocortisonecorticosteroidModerate

    Intervention: Monitor coagulation indices in patients receiving ALKINDI SPRINKLE and concomitant warfarin to maintain the desired anticoagulant effect. (Hydrocortisone label, Drug interactions)

  • HydroxychloroquineQT-prolonging drugModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • IbuprofenNSAIDModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Icosapent ethylomega-3 fatty acidModerate

    Increased Bleeding Risk with Anticoagulants and Antiplatelet Agents: Some published studies with omega-3 fatty acids have demonstrated prolongation of bleeding time. (Icosapent ethyl label, Drug interactions)

  • IndomethacinNSAIDModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • Ketoconazoleazole antifungalModerate

    Anticoagulants and Antiplatelet Drugs rivaroxaban cilostazol, coumarins, dabigatran Cilostazol: Concomitant administration of single doses of cilostazol 100 mg and ketoconazole 400 mg approximately doubled cilostazol concentrations and altered (increase/decrease) the concentrations of the active metabolites of cilostazol. (Ketoconazole label, Drug interactions)

  • KetoprofenNSAIDModerate

    Patients receiving Ketoprofen Capsules, USP who may be adversely affected by alterations in platelet function, such as those with coagulation disorders or patients receiving anticoagulants, should be carefully monitored. (Ketoprofen label, Warnings and precautions)

  • KetorolacNSAIDModerate

    The concurrent use of ketorolac tromethamine and therapy that affects hemostasis, including prophylactic low-dose heparin (2500 to 5000 units q12h), warfarin and dextrans have not been studied extensively, but may also be associated with an increased risk of bleeding. (Ketorolac label, Warnings and precautions)

  • LenalidomideModerate

    A significantly increased risk of DVT (7.4%) and of PE (3.7%) occurred in patients with MM after at least one prior therapy who were treated with REVLIMID and dexamethasone therapy compared to patients treated in the placebo and dexamethasone group (3.1% and 0.9%) in clinical trials with varying use of anticoagulant therapies. (Lenalidomide label, Warnings and precautions)

  • LevomilnacipranSNRIModerate

    Increased Risk of Bleeding : Concomitant use of NSAIDs, aspirin, other antiplatelet drugs, warfarin, and other anticoagulants may increase this risk ( 5.5 ). (Levomilnacipran label, Warnings and precautions)

  • LevonorgestrelprogestinModerate

    …Skyla with caution after careful assessment if any of the following conditions exist, and consider removal of the system if any of them arise during use: • Coagulopathy or use of anticoagulants • Migraine, focal migraine with asymmetrical visual loss or other symptoms indicating transient cerebral ischemia • Exceptionally severe headache • Marked increase of… (Levonorgestrel label, Warnings and precautions)

  • Levothyroxinethyroid hormoneModerate

    Oral Anticoagulants Levothyroxine increases the response to oral anticoagulant therapy. (Levothyroxine label, Drug interactions)

  • Levothyroxine and liothyroninethyroid hormoneModerate

    Drug Interactions Oral Anticoagulants — Thyroid hormones appear to increase catabolism of vitamin K-dependent clotting factors. (Levothyroxine and liothyronine label, Drug interactions)

  • Liothyroninethyroid hormoneModerate

    Oral Anticoagulants Liothyronine sodium increases the response to oral anticoagulant therapy. (Liothyronine label, Drug interactions)

  • LovastatinstatinModerate

    Also, bleeding and/or increased prothrombin time have been reported in a few patients taking coumarin anticoagulants concomitantly with lovastatin. (Lovastatin label, Drug interactions)

  • Mefenamic acidNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy, concomitant use of oral corticosteroids, anti-platelet drugs (such as aspirin), anticoagulants, or selective serotonin reuptake inhibitors (SSRIs), smoking, use of alcohol, older age, and poor general health status. (Mefenamic acid label, Warnings and precautions)

  • MeloxicamNSAIDModerate

    Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Meloxicam label, Warnings and precautions)

  • MercaptopurineantimetaboliteModerate

    Warfarin : Mercaptopurine tablets may decrease the anticoagulant effect. (Mercaptopurine label, Drug interactions)

  • Methimazoleantithyroid drugModerate

    Drug Interactions Anticoagulants (oral): Due to potential inhibition of vitamin K activity by methimazole, the activity of oral anticoagulants (e.g., warfarin) may be increased; additional monitoring of PT/INR should be considered, especially before surgical procedures. β-adrenergic blocking agents: Hyperthyroidism may cause an increased clearance of beta blockers… (Methimazole label, Drug interactions)

  • MethylprednisolonecorticosteroidModerate

    Therefore, coagulation indices should be monitored frequently to maintain the desired anticoagulant effect. (Methylprednisolone label, Drug interactions)

  • MethyltestosteroneandrogenModerate

    DRUG INTERACTIONS Anticoagulants: C-17 substituted derivatives of testosterone, such as methandrostenolone, have been reported to decrease the anticoagulant requirements of patients receiving oral anticoagulants. (Methyltestosterone label, Drug interactions)

  • Metolazonethiazide diureticModerate

    Anticoagulants Metolazone, as well as other thiazide-like diuretics, may affect the hypoprothrombinemic response to anticoagulants; dosage adjustments may be necessary. (Metolazone label, Drug interactions)

  • MetronidazoleantibioticModerate

    Warfarin and Other Oral Anticoagulants : LIKMEZ can potentiate the anticoagulant effect. (Metronidazole label, Drug interactions)

  • Miconazoleazole antifungalModerate

    Warfarin: Miconazole may enhance anticoagulant effect. (Miconazole label, Drug interactions)

  • MifepristoneCYP3A4 inhibitorModerate

    Mifepristone should be used with caution in women who have hemorrhagic disorders or are receiving concurrent anticoagulant therapy. (Mifepristone label, Warnings and precautions)

  • MilnacipranSNRIModerate

    Concomitant use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), warfarin, and other anticoagulants may add to this risk. (Milnacipran label, Warnings and precautions)

  • Minocyclinetetracycline antibioticModerate

    Patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage. (Minocycline label, Drug interactions)

  • MoxifloxacinfluoroquinoloneModerate

    Interacting Drug Interaction Warfarin Anticoagulant effect of warfarin may be enhanced. (Moxifloxacin label, Drug interactions)

  • NabumetoneNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include concomitant use of oral corticosteroids or anticoagulants, longer duration of NSAID therapy, smoking, use of alcohol, older age, and poor general health status. (Nabumetone label, Warnings)

  • NaproxenNSAIDModerate

    Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Naproxen label, Warnings and precautions)

  • Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Naproxen and esomeprazole label, Warnings and precautions)

  • NeomycinaminoglycosideModerate

    Oral neomycin sulfate may enhance the effect of coumarin in anticoagulants by decreasing vitamin K availability. (Neomycin label, Drug interactions)

  • NiacinModerate

    Caution should be observed when niacin extended-release tablets are administered concomitantly with anticoagulants; platelet counts should be monitored closely in such patients. (Niacin label, Warnings and precautions)

  • Nifedipinedihydropyridine calcium channel blockerModerate

    Antithrombotics Coumarins: There have been rare reports of increased prothrombin time in patients taking coumarin anticoagulants to whom nifedipine was administered. (Nifedipine label, Drug interactions)

  • NintedanibModerate

    Anticoagulants Nintedanib is a VEGFR inhibitor and may increase the risk of bleeding. (Nintedanib label, Drug interactions)

  • Anticoagulants warfarin ↑↓ warfarin Closely monitor international normalized ratio (INR) if co-administration with warfarin is necessary. rivaroxaban ↑ rivaroxaban Increased bleeding risk with rivaroxaban. (Nirmatrelvir and ritonavir label, Drug interactions)

  • NitroglycerinnitrateModerate

    Intravenous nitroglycerin administered to heparinized patients may result in a decrease of the partial thromboplastin time with subsequent rebound effect upon discontinuation of nitroglycerin. (Heparin label, Drug interactions)

  • OfloxacinfluoroquinoloneModerate

    Warfarin Some quinolones have been reported to enhance the effects of the oral anticoagulant warfarin or its derivatives. (Ofloxacin label, Drug interactions)

  • Olanzapine and fluoxetineantipsychoticModerate

    Altered anticoagulant effects, including increased bleeding, have been reported when SNRIs or SSRIs are coadministered with warfarin [see Warnings and Precautions ( 5.16 )] . (Olanzapine and fluoxetine label, Drug interactions)

  • Olmesartanangiotensin II receptor blocker (ARB)Moderate

    …Increasing Serum Potassium Concomitant use of olmesartan with other agents that block the renin-angiotensin system, potassium-sparing diuretics (e.g., spironolactone, triamterene, amiloride), potassium supplements, salt substitutes containing potassium or other drugs that may increase potassium levels (e.g., heparin) may lead to increases in serum potassium. (Olmesartan label, Drug interactions)

  • Omega-3-acid ethyl estersomega-3 fatty acidModerate

    Patients taking omega-3-acid ethyl esters capsules and an anticoagulant or other drug affecting coagulation (e.g., anti-platelet agents) should be monitored periodically. (Omega-3-acid ethyl esters label, Drug interactions)

  • OrlistatModerate

    Anticoagulants including Warfarin Vitamin K absorption may be decreased with ORLISTAT. (Orlistat label, Drug interactions)

  • Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • OxaliplatinModerate

    Hemorrhage : Increase frequency of monitoring in patients who are receiving oxaliplatin injection with fluorouracil/leucovorin and oral anticoagulants (5.9) (Oxaliplatin label, Warnings and precautions)

  • OxaprozinNSAIDModerate

    Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, antiplatelet drugs (such as aspirin), anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Oxaprozin label, Warnings and precautions)

  • ParoxetineSSRIModerate

    Increased Risk of Bleeding: Concomitant use of aspirin, nonsteroidal anti-inflammatory drugs, other antiplatelet drugs, warfarin, and other anticoagulant drugs may increase risk. (Paroxetine label, Warnings and precautions)

  • PentoxifyllinemethylxanthineModerate

    DRUG INTERACTIONS Bleeding has been reported in patients treated with pentoxifylline extended-release tablets with or without concomitant NSAIDs, anticoagulants, or platelet aggregation inhibitors. (Pentoxifylline label, Drug interactions)

  • PerindoprilACE inhibitorModerate

    Use of potassium-sparing diuretics (spironolactone, amiloride, triamterene and others), potassium supplements or other drugs capable of increasing serum potassium (indomethacin, heparin, cyclosporine and others) can increase the risk of hyperkalemia. (Perindopril label, Drug interactions)

  • Phenobarbital may decrease the effect of anticoagulants, and necessitate larger doses of the anticoagulant for optimal effect. (Phenobarbital, hyoscyamine, atropine, and scopolamine label, Warnings)

  • PhenytoinanticonvulsantModerate

    …Corticosteroids, doxycycline, estrogens, furosemide, oral contraceptives, paroxetine, quinidine, rifampin, sertraline, theophylline, and vitamin D Drugs whose level is decreased by phenytoin Anticoagulants Apixaban, dabigatran, edoxaban, rivaroxaban Antiepileptic drugs The effect of phenytoin on phenobarbital, valproic acid and sodium valproate serum levels is unpredictable. (Phenytoin label, Drug interactions)

  • Phytonadione (vitamin K1)vitamin KModerate

    Anticoagulants Phytonadione injectable emulsion may induce temporary resistance to prothrombin-depressing anticoagulants, especially when larger doses of phytonadione injectable emulsion are used. (Phytonadione (vitamin K1) label, Drug interactions)

  • Piperacillin and tazobactampenicillin antibioticModerate

    Monitor coagulation parameters in patients receiving Piperacillin and Tazobactam for Injection and Sodium Chloride Injection and heparin or oral anticoagulants. (Piperacillin and tazobactam label, Drug interactions)

  • PiroxicamNSAIDModerate

    Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, antiplatelet drugs (such as aspirin), anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Piroxicam label, Warnings and precautions)

  • PomalidomideModerate

    In Trial 2, where anticoagulant therapies were mandated, thromboembolic events occurred in 8.0% of patients treated with POMALYST and low dose-dexamethasone (Low-dose Dex), and 3.3% of patients treated with high-dose dexamethasone. (Pomalidomide label, Warnings and precautions)

  • PrednisolonecorticosteroidModerate

    Therefore, coagulation indices should be monitored frequently to maintain the desired anticoagulant effect. (Prednisolone label, Drug interactions)

  • PrednisonecorticosteroidModerate

    Anticoagulant agents: May enhance or diminish anticoagulant effects. (Prednisone label, Drug interactions)

  • Propylthiouracilantithyroid drugModerate

    Drug Interactions Anticoagulants (oral) : Due to the potential inhibition of vitamin K activity by propylthiouracil, the activity of oral anticoagulants (e.g., warfarin) may be increased; additional monitoring of PT/INR should be considered, especially before surgical procedures. (Propylthiouracil label, Drug interactions)

  • QuinaprilACE inhibitorModerate

    The anticoagulant effect of a single dose of warfarin (measured by prothrombin time) was not significantly changed by quinapril coadministration twice-daily. (Quinapril label, Drug interactions)

  • QuinidineantiarrhythmicModerate

    By a mechanism that is not understood, quinidine potentiates the anticoagulatory action of warfarin , and the anticoagulant dosage may need to be reduced. (Quinidine label, Drug interactions)

  • QuinineantimalarialModerate

    Warfarin and oral anticoagulants Cinchona alkaloids, including quinine, may have the potential to depress hepatic enzyme synthesis of vitamin K-dependent coagulation pathway proteins and may enhance the action of warfarin and other oral anticoagulants. (Quinine label, Drug interactions)

  • RifapentineantibioticModerate

    …Within Class Antiarrhythmics Disopyramide, mexiletine, quinidine, tocainide Antibiotics Chloramphenicol, clarithromycin, dapsone, doxycycline; Fluoroquinolones (such as ciprofloxacin) Oral Anticoagulants Warfarin Anticonvulsants Phenytoin Antimalarials Quinine Azole Antifungals Fluconazole, itraconazole, ketoconazole Antipsychotics Haloperidol Barbiturates Phenobarbital… (Rifapentine label, Drug interactions)

  • SalsalateNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include concomitant use of oral corticosteroids or anticoagulants, longer duration of NSAID therapy, smoking, use of alcohol, older age, and poor general health status. (Salsalate label, Warnings)

  • SertralineSSRIModerate

    Increased Risk of Bleeding: Concomitant use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), other antiplatelet drugs, warfarin, and other anticoagulants may increase this risk ( 5.3 ) (Sertraline label, Warnings and precautions)

  • SildenafilPDE5 inhibitorModerate

    In addition, the combination of heparin and sildenafil had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans. (Sildenafil label, Warnings and precautions)

  • SimvastatinstatinModerate

    Coumarin Anticoagulants: Obtain INR before ZOCOR initiation and monitor INR during ZOCOR dosage initiation or adjustment. (Simvastatin label, Drug interactions)

  • Anticoagulants: dabigatran etexilate ↑ dabigatran Clinical monitoring of dabigatran is recommended when coadministered with VOSEVI. (Sofosbuvir and velpatasvir label, Drug interactions)

  • Spironolactonealdosterone antagonistModerate

    Examples of drugs that can increase potassium include: ACE inhibitors angiotensin receptor blockers aldosterone blockers non-steroidal anti-inflammatory drugs (NSAIDs) heparin and low molecular weight heparin trimethoprim 7.2 Lithium Like other diuretics, spironolactone oral suspension reduces the renal clearance of lithium, thus increasing the risk of lithium… (Spironolactone label, Drug interactions)

  • Spironolactone and hydrochlorothiazidealdosterone antagonistModerate

    …potassium-sparing diuretics • ACE inhibitors • angiotensin II receptor antagonists • aldosterone blockers • non-steroidal anti-inflammatory drugs (NSAIDs), e.g., indomethacin • heparin and low molecular weight heparin • other drugs or conditions known to cause hyperkalemia • potassium supplements • diet rich in potassium • salt substitutes containing potassium Spironolactone… (Spironolactone and hydrochlorothiazide label, Warnings)

  • SugammadexModerate

    In vitro experiments demonstrated additional aPTT and PT(INR) prolongations for sugammadex in combination with vitamin K antagonists, unfractionated heparin, low molecular weight heparinoids, rivaroxaban, and dabigatran up to ~25% and ~50% at C max levels of sugammadex corresponding to 4 mg/kg and 16 mg/kg doses, respectively. (Sugammadex label, Warnings and precautions)

  • SulfadiazinesulfonamideModerate

    Drug Interactions Administration of a sulfonamide may increase the effect of oral anticoagulants and methotrexate, probably by displacement of these drugs from binding sites on plasma albumin. (Sulfadiazine label, Drug interactions)

  • It has been reported that sulfamethoxazole and trimethoprim may prolong the prothrombin time in patients who are receiving the anticoagulant warfarin. (Sulfamethoxazole and trimethoprim label, Drug interactions)

  • SulindacNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include concomitant use of oral corticosteroids or anticoagulants, longer duration of NSAID therapy, smoking, use of alcohol, older age, and poor general health status. (Sulindac label, Warnings)

  • Other factors that increase the risk for gastrointestinal bleeding in patients treated with NSAIDs include longer duration of NSAID therapy; concomitant use of oral corticosteroids, aspirin, anticoagulants, or selective serotonin reuptake inhibitors (SSRIs); smoking; use of alcohol; older age; and poor general health status. (Sumatriptan and naproxen label, Warnings and precautions)

  • TenecteplaseModerate

    Should serious bleeding that is not controlled by local pressure occur, discontinue any concomitant heparin or antiplatelet agents immediately and treat appropriately. (Tenecteplase label, Warnings and precautions)

  • TestosteroneandrogenModerate

    Frequent monitoring of INR and prothrombin time may be necessary in patients taking anticoagulants, especially at the initiation and termination of androgen therapy. (Testosterone label, Drug interactions)

  • Tetracyclinetetracycline antibioticModerate

    Because the tetracyclines have been shown to depress plasma prothrombin activity, patients who are on anticoagulant therapy may require downward adjustment of their anticoagulant dosage. (Tetracycline label, Drug interactions)

  • Ticagrelorantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • TinidazoleantibioticModerate

    The following drug interactions were reported for metronidazole, a chemically-related nitroimidazole and may therefore occur with tinidazole: Warfarin and other oral coumarin anticoagulants: Anticoagulant dosage may need adjustment during and up to 8 days after tinidazole therapy ( 7.1 ) (Tinidazole label, Drug interactions)

  • Tirofibanantiplatelet agentModerate

    Platelet Inhibitors Drugs such as acetylsalicylic acid, dextran, phenylbutazone, ibuprofen, indomethacin, dipyridamole, hydroxychloroquine and others that interfere with platelet-aggregation reactions (the main hemostatic defense of heparinized patients) may induce bleeding and should be used with caution in patients receiving heparin sodium. (Heparin label, Drug interactions)

  • TolmetinNSAIDModerate

    Other factors that increase the risk for GI bleeding in patients treated with NSAIDs include concomitant use of oral corticosteroids or anticoagulants, longer duration of NSAID therapy, smoking, use of alcohol, older age, and poor general health status. (Tolmetin label, Warnings)

  • TrazodoneantidepressantModerate

    Increased Risk of Bleeding: Concomitant use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), other antiplatelet drugs, warfarin, and other anticoagulants may increase this risk ( 5.5 ). (Trazodone label, Warnings and precautions)

  • TriamcinolonecorticosteroidModerate

    Therefore, coagulation indices should be monitored frequently to maintain the desired anticoagulant effect. (Triamcinolone label, Drug interactions)

  • Triamterene and hydrochlorothiazidepotassium-sparing diureticModerate

    The effect of oral anticoagulants may be decreased when used concurrently with hydrochlorothiazide; dosage adjustments may be necessary. (Triamterene and hydrochlorothiazide label, Drug interactions)

  • Valproic acidanticonvulsantModerate

    The therapeutic relevance of this is unknown; however, coagulation tests should be monitored if valproate therapy is instituted in patients taking anticoagulants. (Valproic acid label, Drug interactions)

  • Valsartanangiotensin II receptor blocker (ARB)Moderate

    …other agents that block the renin-angiotensin system, potassium-sparing diuretics (e.g., spironolactone, triamterene, amiloride), potassium supplements, salt substitutes containing potassium or other drugs that may increase potassium levels (e.g., heparin) may lead to increases in serum potassium and in heart failure patients to increases in serum creatinine. (Valsartan label, Drug interactions)

  • Valsartan and hydrochlorothiazideangiotensin II receptor blocker (ARB)Moderate

    …other agents that block the renin-angiotensin system, potassium-sparing diuretics (e.g., spironolactone, triamterene, amiloride), potassium supplements, salt substitutes containing potassium or other drugs that may increase potassium levels (e.g., heparin) may lead to increases in serum potassium and in heart failure patients to increases in serum creatinine. (Valsartan and hydrochlorothiazide label, Drug interactions)

  • VenlafaxineSNRIModerate

    Concomitant use of aspirin, Nonsteroidal Anti-Inflammatory Drugs (NSAIDs), warfarin, and other anticoagulants may add to this risk. (Venlafaxine label, Warnings and precautions)

  • VilazodoneSSRIModerate

    Increased Risk of Bleeding: Concomitant use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), other antiplatelet drugs, warfarin, and other anticoagulants may increase this risk ( 5.3 ) (Vilazodone label, Warnings and precautions)

  • Vitamin EVitamin and mineralModerate

    Vitamin E can inhibit platelet aggregation and vitamin K-dependent clotting, increasing bleeding risk with anticoagulant and antiplatelet drugs. (NIH Office of Dietary Supplements, Vitamin E)

  • Voriconazoleazole antifungalModerate

    Warfarin (CYP2C9 Inhibition) Other Oral Coumarin Anticoagulants (CYP2C9/3A4 Inhibition) Prothrombin Time Significantly Increased Not Studied In Vivo or In Vitro for other Oral Coumarin Anticoagulants, but Drug Plasma Exposure Likely to be Increased If patients receiving coumarin preparations are treated simultaneously with voriconazole, the prothrombin time or… (Voriconazole label, Drug interactions)

  • VortioxetineantidepressantModerate

    Concomitant use of aspirin, nonsteroidal anti-inflammatory drugs (NSAIDs), warfarin, and other anticoagulants may add to this risk. (Vortioxetine label, Warnings and precautions)

  • Zafirlukastleukotriene receptor antagonistModerate

    Patients on oral warfarin anticoagulant therapy and zafirlukast should have their prothrombin times monitored closely and anticoagulant dose adjusted accordingly (see PRECAUTIONS, Drug Interactions ). (Zafirlukast label, Warnings)

Minor mentions (53)

  • AzathioprineimmunosuppressantMinor

    Use with Warfarin: IMURAN may inhibit the anticoagulant effect of warfarin. (Azathioprine label, Drug interactions)

  • AzelastineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Azelastine and fluticasoneantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Interaction studies with warfarin and acenocoumarol have failed to identify any clinically important effects of benazepril on the serum concentrations or clinical effects of these anticoagulants. (Benazepril and hydrochlorothiazide label, Drug interactions)

  • Anticoagulants: Direct Oral Anticoagulants (DOACs) rivaroxaban dabigatran edoxaban ↑ DOAC Refer to the DOAC prescribing information for concomitant administration with moderate CYP3A inhibitors and/or P-gp inhibitors. (Bictegravir, emtricitabine, and tenofovir alafenamide label, Drug interactions)

  • Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • CarbinoxamineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • CetirizineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Oral Anticoagulants Although clinical studies have not established a cause and effect relationship, physicians should be aware that variable effects on blood coagulation have been reported very rarely in patients receiving oral anticoagulants and chlordiazepoxide hydrochloride, a component of Librax. (Chlordiazepoxide and clidinium label, Drug interactions)

  • ChlorpheniramineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • ChlorpromazineantipsychoticMinor

    Chlorpromazine diminishes the effect of oral anticoagulants. (Chlorpromazine label, Precautions)

  • ClemastineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • CyproheptadineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • DesloratadineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • DexchlorpheniramineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Digoxindigitalis glycosideMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • DimenhydrinateantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Dinoprostoneprostaglandin analogMinor

    Therapy consisting of prompt removal of the source of procoagulant material, replacement of depleted clotting factors and, in some cases, anti-coagulation with heparin should be instituted promptly. (Dinoprostone label, Warnings and precautions)

  • DiphenhydramineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • DobutaminesympathomimeticMinor

    Drug Interactions There was no evidence of drug interactions in clinical studies in which dobutamine was administered concurrently with other drugs, including digitalis preparations, furosemide, spironolactone, lidocaine, glyceryl trinitrate, isosorbide dinitrate, morphine, atropine, heparin, protamine, potassium chloride, folic acid, and acetaminophen. (Dobutamine label, Drug interactions)

  • DoxylamineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Doxylamine and pyridoxineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • DronedaroneantiarrhythmicMinor

    More patients experienced clinically significant INR elevations (≥5) usually within 1 week after starting dronedarone versus placebo in patients taking oral anticoagulants in ATHENA. (Dronedarone label, Drug interactions)

  • FexofenadineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Fish oil (omega-3)Herbal and supplementMinor

    Omega-3 supplements may mildly prolong bleeding time; the combination with anticoagulants such as warfarin warrants monitoring, though clinically significant bleeding has not been consistently shown. (NIH Office of Dietary Supplements, Omega-3 Fatty Acids)

  • FlecainideantiarrhythmicMinor

    Consequently, interactions with other drugs which are highly protein bound (e.g., anticoagulants ) would not be expected. (Flecainide label, Drug interactions)

  • FosamprenavirantiretroviralMinor

    Anticoagulant: Warfarin Concentrations of warfarin may be affected. (Fosamprenavir label, Drug interactions)

  • FosinoprilACE inhibitorMinor

    In a pharmacokinetic interaction study with warfarin, bioavailability parameters, the degree of protein binding, and the anticoagulant effect (measured by prothrombin time) of warfarin were not significantly changed. (Fosinopril label, Drug interactions)

  • Interaction studies with warfarin have failed to identify any clinically important effects of fosinopril on the serum concentration or clinical effects of the anticoagulant. (Fosinopril and hydrochlorothiazide label, Drug interactions)

  • Garlic (supplement)Herbal and supplementMinor

    Garlic supplements may increase bleeding risk with anticoagulants such as warfarin. (NCCIH, Garlic)

  • Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • HydroxyzineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • ImatinibCYP3A4 inhibitorMinor

    Patients who require anticoagulation should receive low-molecular weight or standard heparin and not warfarin. (Imatinib label, Drug interactions)

  • LenacapavirantiretroviralMinor

    Anticoagulants: Direct Oral Anticoagulants (DOACs) rivaroxaban dabigatran edoxaban ↑ DOAC Refer to the DOAC prescribing information for concomitant administration with moderate CYP3A inhibitors and/or P-gp inhibitors. (Lenacapavir label, Drug interactions)

  • LevocetirizineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Lopinavir and ritonavirantiretroviralMinor

    Anticoagulants: warfarin, rivaroxaban ↑↓ warfarin ↑ rivaroxaban Concentrations of warfarin may be affected. (Lopinavir and ritonavir label, Drug interactions)

  • LoratadineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • MeclizineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • MefloquineantimalarialMinor

    Nevertheless, the effects of mefloquine on travelers receiving concomitant medications, particularly diabetics or patients using anticoagulants, should be checked before departure. (Mefloquine label, Drug interactions)

  • MethohexitalbarbiturateMinor

    Arterial injection of heparin at the site of injury, followed by systemic anticoagulation. (Methohexital label, Warnings)

  • MexiletineantiarrhythmicMinor

    In a large compassionate use program mexiletine has been used concurrently with commonly employed antianginal, antihypertensive, and anticoagulant drugs without observed interactions. (Mexiletine label, Drug interactions)

  • MilrinonePDE3 inhibitorMinor

    …been observed in limited experience with patients in whom milrinone was used concurrently with the following drugs: digitalis glycosides; lidocaine, quinidine; hydralazine, prazosin; isosorbide dinitrate, nitroglycerin; chlorthalidone, furosemide, hydrochlorothiazide, spironolactone; captopril; heparin, warfarin, diazepam, insulin; and potassium supplements. (Milrinone label, Drug interactions)

  • MoexiprilACE inhibitorMinor

    Oral Anticoagulants: Interaction studies with warfarin failed to identify any clinically important effect on the serum concentrations of the anticoagulant or on its anticoagulant effect. (Moexipril label, Drug interactions)

  • OlopatadineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Olopatadine and mometasoneantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • ProchlorperazineantipsychoticMinor

    Phenothiazines can diminish the effect of oral anticoagulants. (Prochlorperazine label, Precautions)

  • PromethazineantihistamineMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Tigecyclinetetracycline antibioticMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • Tobacco and smokingTobacco and cannabisMinor

    Other Interactions Digitalis, tetracyclines, nicotine, or antihistamines, or intravenous nitroglycerin may partially counteract the anticoagulant action of heparin sodium. (Heparin label, Drug interactions)

  • TrandolaprilACE inhibitorMinor

    The anticoagulant effect of warfarin was not significantly changed by trandolapril. (Trandolapril label, Drug interactions)

  • TrifluoperazineantipsychoticMinor

    Phenothiazines may diminish the effect of oral anticoagulants. (Trifluoperazine label, Precautions)

No significant interaction reported (4)

  • AcitretinretinoidNo interaction

    Investigations into the effect of acitretin on the protein binding of anticoagulants of the coumarin type (warfarin) revealed no interaction. (Acitretin label, Drug interactions)

  • Anastrozolearomatase inhibitorNo interaction

    Warfarin In a study conducted in 16 male volunteers, anastrozole did not alter the exposure (as measured by C max and AUC) and anticoagulant activity (as measured by prothrombin time, activated partial thromboplastin time, and thrombin time) of both R- and S-warfarin. (Anastrozole label, Drug interactions)

  • Bumetanideloop diureticNo interaction

    Anticoagulants Interaction studies in humans have shown bumetanide to have no effect on warfarin metabolism or on plasma prothrombin activity. (Bumetanide label, Drug interactions)

  • FesoterodineanticholinergicNo interaction

    Warfarin A clinical study has shown that fesoterodine 8 mg once daily has no significant effect on the pharmacokinetics or the anticoagulant activity (PT/INR) of warfarin 25 mg. (Fesoterodine label, Drug interactions)

Check Heparin against everything you take. Add your full list; every pair is checked at once.

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Not medical advice. Severity reflects the label's wording, not your circumstances. A "major" flag can be routine under supervision and a "minor" one can matter at high doses. Ask a pharmacist.