Coca leaf as a therapeutic agent.

South American Indians have used coca leaf as a remedy for thousands of years. Coca might be useful as a treatment for gastrointestinal ailments and motion sickness, as a fast-acting antidepressant medication, as a substitute stimulant for coffee in certain cases, and as an adjunct in programs of weight reduction and physical fitness. In leaf form, coca does not produce toxicity or dependence. Its effects are distinct from those of cocaine, which is but one of a number of active compounds in the leaf. Coca can be administered as a chewing gum containing a whole extract of the leaf, including alkaloids, natural flavors, and several nutrients. Legal mechanisms exist for importing, distributing, and dispensing coca, and experimentation with it by interested physicians would be valuable.