Tricyclic antidepressants anticoagulants

Drugs that may be affected by estrogens include oral anticoagulants, tricyclic antidepressants, hydantoins, corticosteroids, and thyroid hormones. 

Drugs that may affect methylphenidate include MAOIs. Drugs that may be affected by methylphenidate hydrochloride include guanethidine, anticonvulsants (eg, phenytoin, phenobarbital, primidone), selective serotonin reuptake inhibitors, coumarin anticoagulants, and tricyclic antidepressants. 

Drugs that can decrease carbamazepine serum levels include charcoal, cisplatin, doxorubicin, felbamate, hydantoins, rifampin, phenobarbital, primidone, theophylline. The serum levels of oral contraceptives, haloperidol, bupropion, anticoagulants, felbamate, valproic acid, felodipine, tricyclic antidepressants, acetaminophen, ziprasidone, voriconazole, topiramate, tiagabine, olanzapine, and lamotrigine can be lowered by carbamazepine. 

Drugs that may affect ketoconazole include antacids, didanosine, histamine H2 antagonists, isoniazid, sucralfate, proton pump inhibitors, and rifampin. Drugs that may be affected by ketoconazole include oral anticoagulants, corticosteroids, cyclosporine, protease inhibitors, tricyclic antidepressants, carbamazepine. 

Drugs that may interact with rifabutin include the following Anticoagulants, azole antifungal agents, benzodiazepines, beta blockers, buspirone, corticosteroids, cyclosporine, delavirdine, doxycycline, hydantoins, indinavir, rifamycins, losartan, macrolide antibiotics, methadone, morphine, nelfinavir, quinine, quinidine, theophylline, aminophylline, tricyclic antidepressants, and zolpidem. 

Antihypertensives, diuretics, antipsychotics, tricyclic antidepressants, levodopa, dopamine agonists, a-blockers Corticosteroids NSAIDs, anticoagulants -Blockers (non-selective)... 

Tricyclic antidepressants, corticosteroids, coumarin anticoagulants, digitoxin, doxycycline, furosemide, oral contraceptives, quinidine, rifampin, theophylline, vitamin D... 

Tricyclic antidepressants can interfere with the metabolism of oral anticoagulants, increase their serum concentrations, and prolong their half-lives by as much as 300% (SEDA-21,10) (161). Prothrombin activity should be carefully monitored in patients taking oral anticoagulants. 

May inhibit metabolism of SSRIs, anticonvulsants (phenobarbital, phenytoin, primidone), tricyclic antidepressants, and coumarin anticoagulants, requiring downward dosage adjustments of these drugs... 

Drug Interactions Contraceptive effects are decreased when "the pill" is taken with ANTIDIOTICS (ampicillin, isoniazid, neomycin, pen V, rifampin, sulfonamides, tetracycline) or CNS AGENTS (barbiturates, benzodiazepines, phenytoin). Contraceptives increase the effects of corticosteroids and worsen side effects of tricyclic antidepressants. Oral contraceptives decrease the effectiveness of oral anticoagulants, anticonvulsants, and oral hypoglycemic agents. 

Not understood. One suggestion is that the tricyclic antidepressants inhibit the metabolism of the anticoagulant (seen in animals with nortriptyline or amitriptyline and warfarin, but not with desipramine and acenocoumarol ), but tricyclics are not established known inhibitors of the metabolism of any drug so this seems unlikely. Another idea is that the tricyclics slow gastrointestinal motility thereby increasing the time available for the dissolution and absorption of dicoumarol. ... 

Information about interactions between anticoagulants and tricyclic antidepressant is limited, patchy and inconclusive. It appears that amitriptyline and nortriptyline do not alter the half-life of warfarin, but might increase that of dicoumarol. A greater fluctuation in anticoagulant control was noted in two analyses, one with warfarin and one with phenprocoumon. However, these were uncontrolled studies, and the findings need confirming in a randomised study. Moreover, there do not appear to be any... 

Neither cimetidine nor rifampicin had any clinically relevant effect on the pharmacokinetics of nicorandil. Nicorandil did not alter the anticoagulant effects of acenocoumarol. Although animal studies surest antagonism of effects, a study in patients found no pharmacodynamic interaction between nicorandil and glibenclamide. Nicorandil may potentiate the hypotensive effects of other vasodilators, tricyclic antidepressants and alcohol. 

See also Anticoagulants, oral Antidepressants, tricyclic Azole antifungals Calcium channel blockers. 

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