Clinical pharmacology and pharmacokinetics of pirmenol

Pirmenol hydrochloride is a promising antiarrhythmic agent with quinidine-like (Class Ia) properties presently undergoing evaluation. It's clinical pharmacology and pharmacokinetics are reviewed. The author outlines the effects of pirmenol on the sinus node, atrial tissue, A-V node, and ventricular tissue and describes its antiarrhythmic efficacy in clinical studies to date, including his own study in 21 patients with a history of sustained ventricular tachycardia. The author summarizes the hemodynamic and pharmacokinetic studies of pirmenol noting that its effects are relatively independent of potassium concentration. The drug's side effects profile is presented, and it is concluded that pirmenol is well tolerated. Hypotension has not been a significant problem with intravenous pirmenol. Precipitation or worsening of clinical heart failure appears to occur only rarely. The favorable pharmacokinetics of pirmenol permit dosage at less frequent intervals than with procainamide, quinidine, disopyramide. Pirmenol has shown efficacy for ventricular arrhythmias even in some patients refractory to Class Ia agents. Antiarrhythmic effects appear to be correlated with plasma levels, and a well-defined therapeutic minimum has been determined.