Definition

The hydrochloride salt form of lidocaine, an aminoethylamide and a prototypical member of the amide class anesthetics. Lidocaine interacts with voltage-gated Na+ channels in the nerve cell membrane and blocks the transient increase in permeability of excitable membranes to Na+. This prevents the generation and conduction of nerve impulses and produces a reversible loss of sensation. Lidocaine hydrochloride also exhibits class IB antiarrhythmic effects. The agent decreases the flow of sodium ions into myocardial tissue, especially on the Purkinje network, during phase 0 of the action potential, thereby decreasing depolarization, automaticity and excitability.