Potentiation of warfarin by trimethoprim-sulfamethoxazole.
Potentiation of warfarin by trimethoprim-sulfamethoxazole (TMP-SMX) has been reported occasionally but not in the urologic literature. Three cases are presented in which significant bleeding developed when TMP-SMX was added for the patient already on warfarin anticoagulants. The mechanism of this interaction is uncertain but probably involves competitive protein binding by the two drugs.
D000368:Aged; D004357:Drug Synergism; D004844:Epistaxis / Q000139:chemically induced; D005260:Female; D006417:Hematuria / Q000139:chemically induced; D006801:Humans; D008297:Male; D008875:Middle Aged; D013420:Sulfamethoxazole / Q000494:pharmacology*; D014295:Trimethoprim / Q000494:pharmacology*; D014859:Warfarin / Q000494:pharmacology*
D014859:Warfarin; D014295:Trimethoprim; D013420:Sulfamethoxazole