title: Continuation of warfarin-nafcillin interaction during dicloxacillin therapy.
abstract: Interactions between warfarin and penicillins have been infrequently reported. A case report of a single patient who experienced the effects of a warfarin-nafcillin interaction as well as a warfarin-dicloxacillin interaction is presented. Clinical effects of this interaction were documented primarily through changes in prothrombin time (PT) and the need for higher warfarin dosing. While the patient received nafcillin, warfarin doses were increased to as much as 4.5 times the previous amounts needed to provide adequate anticoagulation. During dicloxacillin therapy, warfarin doses were gradually decreased, but stabilized to a maintenance dose higher than the patient's pre-nafcillin dose. The dicloxacillin-warfarin interaction appears similar to that noted during nafcillin-warfarin combination.
authors.affiliation: Department of Pharmacy Practice, University of Georgia College of Pharmacy, Athens.
authors.forename: A T
authors.initials: AT
authors.lastname: Taylor
authors.forename: D C
authors.initials: DC
authors.lastname: Pritchard
authors.forename: A O
authors.initials: AO
authors.lastname: Goldstein
authors.forename: J L
authors.initials: JL
authors.lastname: Fletcher
mesh_terms: D000328:Adult; D001021:Aortic Valve; D004009:Dicloxacillin / Q000493:pharmacokinetics / Q000627:therapeutic use*; D004347:Drug Interactions; D016903:Drug Monitoring; D004359:Drug Therapy, Combination; D004697:Endocarditis, Bacterial / Q000097:blood / Q000188:drug therapy*; D006350:Heart Valve Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D009254:Nafcillin / Q000493:pharmacokinetics / Q000627:therapeutic use*; D016459:Prosthesis-Related Infections / Q000097:blood / Q000188:drug therapy*; D011517:Prothrombin Time; D014859:Warfarin / Q000493:pharmacokinetics / Q000627:therapeutic use*
chemical_list: D009254:Nafcillin; D014859:Warfarin; D004009:Dicloxacillin