Casodex & Warfarin

AstaZeneca, a global research-based biopharmaceutical company, manufactures the prostate prescription drug Casodex (generic Bicalutamide) that is indicated for the treatment of prostate cancer. Because the once-a-day treatment carries the risk of interacting with warfarin, AstaZeneca recommends more frequent International Normalized Ratio (INR) monitoring. According to the package insert, “When Casodex 50 mg (and 150mg) is started in patients who are already receiving warfarin anticoagulants, prothrombin time should be closely monitored.”1

More frequent monitoring is recommended as the method to reduce the risk of drug-to-drug interactions between Casodex® prescription drug and warfarin. A change in warfarin dose may be needed.1

More frequent home INR monitoring can help both the patient and physician identify drug interactions sooner than those who test their INR less frequently,2 and possibly prevent a dangerous side effect with warfarin. Patients who consider taking Casodex® prescription drug , while taking warfarin should inform their physicians.

  1. AstraZeneca Pharmaceuticals, 2009. CASODEX® Package Insert.