Medical aspects of the chewing of khat leaves.

The khat plant (Catha edulis) is produced in certain areas of East Africa and the Arabian peninsula, and the leaves are chewed for their stimulating effect. Fresh material, which is preferred by users, contains a substance that is rapidly converted to (+)-norpseudoephedrine. As a consequence of the traditional means of consumption, intoxication with khat is self-limiting but chronic consumption can cause certain disturbances to the health of the user and may also lead to social and economic damage to the individual and the community.