Pharmacology of lorcainide

Lorcainide is a new type 1 antiarrhythmic drug that is well absorbed orally, with bioavailability increasing with both dose and continued administration. It is metabolized through the liver, and patients with significant liver disease will require dosage reduction. The drug has an active metabolite, norlorcainide, whose activity is similar to that of lorcainide but whose half-life is 26 hours instead of 8 for the parent compound. The levels of this metabolite are nearly twice those of lorcainide at steady state. The long half-life of the metabolite and the changing bioavailability of lorcainide require that a given dose be administered for 1 week for the maximum effect to be demonstrated.