Procainamide Hydrochloride

**Semantic type:** Pharmacologic Substance

**Definition:** The hydrochloride salt form of procainamide, an amide derivative exhibiting class 1A antiarrhythmic property and analog of procaine. Procainamide hydrochloride reversibly binds to and blocks activated (open) voltage-gated sodium channels, thereby blocks the influx of sodium ions into the cell, which leads to an increase in threshold for excitation and inhibit depolarization during phase 0 of the action potential. In addition, the effective refractory period (ERP), action potential duration (APD), and ERP/APD ratios are increased, resulting in decreased impulse conduction velocity. The lasting action potential may also be due to blockage of outward K+ currents. The result is a decrease in automaticity, increase in refractory period and slowing of impulse conduction.

**Synonyms:** - Benzamide, 4-amino-N-(2-(diethylamino)ethyl)-, Monohydrochloride - Novocamid Hydrochloride - PROCAINAMIDE HYDROCHLORIDE - Procan SR - Promine - Pronestyl - Pronestyl-SR