curare

Organic compound, an alkaloid that occurs in various tropical American plants (mostly of the genus Strychnos) and causes paralysis. Crude preparations have long been used by native people as an arrow poison. It relaxes skeletal muscle by competing with acetylcholine at nerve endings. A purified form is used in anesthesiology to prevent any movement of patients during surgery. Small amounts bring profound relaxation, with prompt recovery and few complications.