Cocaine is an alkaloid that is derived from the leaves of various species of Erythroxylon - coca plants - or produced synthetically.
It is used extensively in ENT as a nasal local anaesthetic. It is a potent vasoconstrictor.
As an abused drug:
Cocaine was obtained by South American Indians from the leaves of the coca shrub. It was popularised in late nineteenth century middle-class Europe.
- when cocaine is first isolated from the plant, it is in its base form and is an alkaloid. Crushing and pressing the coca leaves and adding sulphuric acid and water turn it into a crystalline salt form. It then goes through a series of changes in the salt-base cycle ending up as cocaine hydrochloride powder
- cocaine is illegally imported from S. America as a white powder and is colloquially refered to as coke or snow. Cocaine is usually sniffed or snorted from a spoon or tube, and absorbed via the nasal mucosa
- stimulant effects wane after 20-30 minutes
- to transform cocaine powder into crack, the cocaine base has to be freed from the salt and to do that the powder is heated up in a microwave with bicarbonate of soda and water. Crack is easily melted and vaporised, so it can be smoked. Crack can also be injected by mixing with water and a weak acid, such as citric or ascorbic acid
Reference: