Ketoconazole at 400 mg daily (the maximum approved prescription dose) co-administered with TIKOSYN (500 mcg BID) for 7 days has been shown to increase dofetilide Cmax by 53% in males and 97% in females, and AUC by 41% in males and 69% in females.
<Ketoconazole, mechanism, TIKOSYN>