Khat and neurobehavioral functions: a systematic review

Khat is an African endemic plant that is used for its amphetamine-like stimulant properties. However, regardless its popularity in Eastern Africa, Arabian Peninsula, and the Middle East studies researching the possible neurobehavioral impairment derived from khat use are lacking.

A systematic review was conducted to identify studies that assessed the effects of khat use on neurobehavioral functions. MedLine, Scopus, Cochrane, Web of Science and Open Grey literature were searched for relevant publications from inception to December 2020. A total of 142 articles were reviewed, 14 of which met the inclusion criteria (nine human and five rodent studies). Available human studies suggest that long term khat use is associated with significant deficits in several cognitive domains, including learning, motor speed/coordination, set-shifting/response inhibition functions, cognitive flexibility, short term/working memory, and conflict resolution. In addition, rodent studies indicated daily administration of khat extract resulted in dose-related impairments in behavior such as motor hyperactivity and decreased cognition, mainly learning and memory.

The findings presented in this review indicates that long-term khat use may be contributing to an impairment of neurobehavioral functions. However, gaps in literature were detected that future studies could potentially address to better understand the health consequences of khat use.

The authors have declared that no competing interests exist. Ayan Ahmed was supported financially by the Society for the Study of Addiction (SSA).