Detrimental effects of divalproex on warfarin therapy following mechanical valve replacement.

ABSTRACT

Drug interaction between Warfarin and psychiatric agents may have important therapeutic effects for patients undergoing cardiac surgery. We present a case of a patient in whom concurrent treatment with Warfarin and valproic acid resulted in supratherapeutic international normalized ratio values. A discussion of the possible mechanisms for this interaction as well as a review of interactions between Warfarin and other psychiatric medications is the subject of this case report.