Tiracizine

Tiracizine is a new class I antiarrhythmic agent that has been investigated for its efficacy in treating ventricular arrhythmias and ischemic heart disease. Pharmacokinetic studies in healthy volunteers have detailed its disposition, including serum and urine kinetics of the parent compound and its three metabolites (M1, M2, M3). The drug exhibits non-linear kinetics, with considerable accumulation of metabolites during repeated dosing. Its bioavailability is influenced by food intake, which appears to alter hepatic first-pass metabolism, specifically reducing N-demethylation. Tiracizine has been shown to prolong PQ and QRS intervals in a dose-dependent manner, suggesting its mechanism of action involves affecting cardiac conduction. Patients are advised to take the drug consistently with respect to food to ensure stable bioavailability.