What effect does fluconazole have on warfarin therapy?

Fluconazole is known to interact with warfarin by increasing its anticoagulant effects. This occurs primarily because fluconazole inhibits certain cytochrome P450 enzymes involved in the metabolism of warfarin. When these enzymes are inhibited, the clearance of warfarin from the body is reduced, resulting in higher levels of warfarin in the bloodstream. Increased warfarin levels heighten the risk of bleeding, which is a significant concern for patients on anticoagulation therapy.

Understanding this interaction is crucial for healthcare providers managing patients who require both warfarin and antifungal treatment with fluconazole. Monitoring the patient’s International Normalized Ratio (INR) becomes important to ensure that anticoagulation is maintained within a safe range, preventing complications associated with over-anticoagulation.