Flutamide Warfarin

FLUTAMIDE ANTICOAGULANTS-WARFARIN t anticoagulant effect Uncertain possibly inhibition of hepatic enzymes Monitor INR at least weekly until stable at initiation and discontinuation of concurrent therapy... 

Sex hormones and hormone antagonists. Oestrogens increase the synthesis of some vitamin K dependent clotting factors and progestogen-only contraceptives are preferred. The hormone antagonists danazol, flutamide and tamoxifen enhance the effect of warfarin. 

Acetaminophen, acetanilide, aminopyrine, antipyrine, aromatic amines, chlorzoxazone, clozapine, 17/3-estradiol, flutamide, imipramine,lidocaine,((S)-and (i )-mianserin, (S)- and (J )-naproxen, phenacetin, propafenone, tacrine, tamoxifen, theophylline, trimethadone, verapamil, (7 )-warfarin, zolpidem... 

Acetaminophen, aldrin, alfentanil, amiodarone, aminopyrine, amitriptyline, amprenavir, androstenedione,antipyrine, astemizole, benzphetamine, budesonide, carbamazepine, celecoxib, chlorpromazine, chlorzoxazone, cisapride, clarithromycin, clozapine, cocaine, codeine, cortisol, cyclophosphamide,cyclosporin, dapsone, delavirdine, dextromethorphan, digitoxin, diltiazem, diazepam, erythromycin, 17j3-estradiol, ethinylestradiol, etoposide, felbamate, fentanyl, flutamide, hydroxyarginine, ifosphamide, imipramine, indinavir, ketoconazole, lansoprazole, loratidine, losartan, lovastatin, (iS)"mephen3d in, methadone, mianserin, miconazole, mifepristone, nelfinavir, nevirapine, nicardipine, nifedipine, odansetron, omeprazole, orphenadrine, proguanil, propafenone, quinidine, quinine, rapamycin, retinoic acid, ritonavir, saquinavir, selegiline, serindole, sufentanil, sulfinpyrazone, tacrolimus, tamoxifen, tamsulosin, taxol, teniposide, terfenadine, tetrahydrocannabinol, theophylline, toremifene, triazolam, trimethadone, trimethoprim, troleandomycin, verapamil, warfarin, zatosetron, Zolpidem, zonisamide... 

The manufacturer has on record a few cases of flutamide possibly increasing the anticoagulant effects of warfarin. In vitro, bicalutamide displaced warfarin from its protein binding sites. The clinical relevance of this, if any, has not been assessed. In vitro, nilutamide inhibited P450 isoenzymes, and might therefore interact with coumarins, although there does not appear to be any further information on this. 

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