Oxandrin (oxandrolone, USP)
Audience: Physicians, pharmacists, and other healthcare professionalsSavient Pharmaceuticals, Inc. notified healthcare professionals of an important drug interaction between Oxandrin, a synthetic derivative of testosterone, and the oral anticoagulant warfarin for systemic anticoagulation. Oxandrin is indicated as adjunctive therapy to promote weight gain and for the relief of the bone pain frequently accompanying osteoporosis. Concurrent dosing of Oxandrin and warfarin may result in unexpectedly large increases in the International Normalized Ratio (INR) or prothrombin time (PT). When Oxandrin is prescribed to patients being treated with warfarin, doses of warfarin may need to be decreased significantly to maintain a desirable INR level and diminish the risk of potentially serious bleeding.
[April 20, 2004 Letter - Savient Pharmaceuticals]