Cocaine is the alkaloid of coca, and is used as the hydrochloride.

It has no action on the unbroken skin, but is absorbed readily from mucous membranes, which it anesthetizes.

Its principal action is as a local anesthetic, benumbing the peripheral sensory nerves. After absorption it slightly stimulates the heart, contracts the blood vessels, stimulates and excites the brain, and applied locally dilates the pupils. Toxic doses cause death by paralysis of the respiratory center.

It is excreted in the urine.