An overview of in vivo toxicological profile of thymoquinone

Thymoquinone (TQ) is a naturally occurring quinone derivative and its metabolism may produce reactive oxygen species which in turn may lead to various adverse effects. Here, we discuss in vivo data concerning toxicological effects of TQ. Previous studies showed LD50 values of 250-794 mg/kg in rats and 300-2400 mg/kg in mice for oral TQ but 57 mg/kg in rats and 90.3-104 mg/kg in mice for intraperitoneal TQ. In subacute toxicity evaluations, NOAEL was about 10 mg/kg. Though TQ has been found as an almost safe chemical, detailed studies are required before introducing TQ as a therapeutic agent for human use.