Clinical pharmacology of the neuromuscular blocking agents

Neuromuscular blocking agents are among the most commonly used drugs during general anesthesia. They compete with acetylcholine and interfere with the transmission of nerve impulses resulting in skeletal muscle relaxation. Based on their mechanism of action, neuromuscular blocking agents are classified as either depolarizing or nondepolarizing. Succinylcholine is a short-acting depolarizing agent. Commonly used nondepolarizing agents are curare (long-acting), pancuronium (long-acting), atracurium (intermediate-acting), and vecuronium (intermediate-acting). Neuromuscular blocking agents are used clinically to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgery. This article provides an overview of the physiology of the neuromuscular transmission and summarizes our current knowledge on the use of these agents during general anesthesia.