Khat-related liver disease in sub-Saharan Africa: neglected, yet important reply

The question of khat's liver toxicity is complex. It contains numerous compounds, including alkaloids, terpenoids, flavonoids, sterols, glycosides, tannins, amino acids, vitamins, and minerals.5 Research into the deleterious effects of khat has largely concentrated on the pharmacological effects of cathinone and cathine on the cardiovascular system and CNS, and studies on possible liver toxicity in humans are restricted to Ethiopia and Somaliland and to reports from western Europe almost exclusively involving Somali men. Additional research is necessary to establish the prevalence of liver toxicity in people who chew khat in Ethiopia versus Djibouti (where liver toxicity is apparently not observed)6 and Yemen (which has the highest proportion of users worldwide),7 and in Kenya, Uganda, and Madagascar, where studies have not been done. Also necessary is investigating the mechanisms and progression of liver damage induced by khat, the effects of gender (khat toxicity is observed much more frequently in males)8 and genetics (genetic variants in CYP2D6 might play a role in liver toxicity),9 and the contribution of other compounds found in khat and of contaminating herbicides and pesticides to liver disease.10 Current evidence shows that hepatitis viruses and alcohol are the main contributors to the incidence of liver cirrhosis throughout sub-Saharan Africa1 and efforts should continue to curb their effects. We declare no competing interests