Cocaine
Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is both a stimulant of the central nervous system and an appetite suppressant. Because of the way it affects the mesolimbic reward pathway, cocaine is extremely addictive. Its possession, cultivation, and distribution are illegal for non-medicinal and non-government sanctioned purposes in virtually all parts of the world. Cocaine is a potent central nervous system stimulant. Its effects can last from 20 minutes to several hours, depending upon the dosage of cocaine taken, purity, and method of administration. The initial signs of stimulation are hyperactivity, restlessness, increased blood pressure, increased heart rate and euphoria. The euphoria is sometimes followed by feelings of discomfort and depression and a craving to experience the drug again.