A green-leafed shrub (Catha edulis) whose leaves are chewed with the subsequent release of psychoactive agents. It is usually placed in the mucobuccal fold for several hours and is often accompanied by smoking tobacco. It is reported to be associated with periodontitis, leukoplakia, and oral cancer.
El-Wajeh Y. A. M., Thornhill M. H. Qat and its health effects. Br Dent J 2009;206:17–21.