Bepridil

Bepridil is a non-dihydropyridine calcium channel blocker that has been used as an antianginal and antiarrhythmic medication. It is notable for its long duration of action and high lipophilicity.

Bepridil pharmacology involves blocking L-type calcium channels in cardiac muscle and vascular smooth muscle, and it also inhibits various cardiac potassium channels, particularly I_Kr. This combination prolongs repolarization and the QT interval, providing antianginal effects but increasing the risk of torsades de pointes.

Historically, bepridil was prescribed for angina pectoris and certain supraventricular tachyarrhythmias. Because of the risk of QT prolongation, it is rarely used in modern practice, and regulatory actions in many markets have restricted or removed its use.

Pharmacokinetically, bepridil is well absorbed when given orally and is highly lipophilic with extensive tissue distribution. It undergoes hepatic metabolism with a long elimination half-life and notable tissue accumulation. Elimination is primarily hepatic with biliary excretion.

Safety considerations center on the drug’s potential to prolong the QT interval and provoke torsades de pointes, especially in patients with electrolyte disturbances, bradycardia, or concomitant QT-prolonging drugs. Additional adverse effects may include dizziness, hypotension, and gastrointestinal upset. Due to safety concerns, bepridil’s usage has declined and it is no longer widely marketed in many countries.