Khat

Khat or qat, Catha edulis is a flowering plant native to eastern and southeastern Africa. It has a history of cultivation originating in the Harar area (present day eastern Ethiopia) and subsequently introduced at different times to countries nearby in East Africa and Southern Arabia, most notably Yemen. Cultivated by farmers, its leaves are sold on the market to be chewed as a recreational stimulant. The world's largest consumers are Eastern Africans, particularly Somalis, and nearby Yemen; with the largest producers/exporters being Ethiopia and Kenya, Khat contains the alkaloid cathinone, a stimulant which causes greater sociability, excitement, mild loss of appetite and mild euphoria. Among communities from the areas where the plant is native, khat-chewing has historical relevance (as a social custom, especially among men) dating back thousands of years, analogous—but slightly different—to the use of coca leaves in South America's Andes Mountains or the betel nut preparations in South Asia.

Source: Wikipedia