Toxicity of coenzyme Q(10): a report of 90-day repeated dose toxicity study in rats

Potential toxicity of CoQ(10) was studied in rats by oral gavage for 90 days at 500, 1500, and 3000 mg/kg.day. A 15-day recovery period after the administration period was investigated. Body weight and food consumption were measured throughout the study. Meanwhile, clinical observations were recorded. Hematological and blood chemistry parameters were evaluated at both the end of the dosing period and the end of the recovery period. Gross-pathologic and histopathologic examination was performed on select tissues from all animals. No adverse changes in mortality and clinical signs occurred. The body weights of males in the 1500 mg/kg dosage group were slightly reducted; likewise, the food consumption in 3000 mg/kg female rats decreased, but this is not a dose-dependent behavior. Significant change of liver function (TRIGL) and CHOL did not show a dose-dependent effect. Weight of ovary and ovary-to-body weight ratio decreased in the 1500 mg/kg dosage groups. Meanwhile, the uterus -to-body weight ratio increased the in 3000 mg/kg dosage groups. However, there were no significant histopathological changes observed in ovary and uterus: so they were not considered to be adverse. It suggested that CoQ(10) is relatively safe on the test dosage administration. Nevertheless, appetite the body weight, blood lipid and liver function should be observed during long-term clinical administration of this drug with high dosage. Overall, CoQ(10) was well tolerated by male and female rats at dose levels up to 3000 mg/kg.day.