Subchronic toxicity studies of the ethanolic root extract of Croton zambesicus.

Subchronic toxicity study of the crude root extract of Croton zambesicus (27-81 mg/kg), which is used traditionally as malarial remedy, was carried out in rodents to evaluate the safety profile. Effect of the extract on body weights, haematological indices as well as liver and kidney functions and histology of various organs were investigated. Subchronic treatment of rats for 21 days caused comparable increase in body weights of rats in extract treated and control groups. The extract caused a dose-dependent increases in RBC, PCV, Hb, WBC, bleeding time and clotting time. The increases were only significant (P<0.05) at the highest dose of the extract (81 mg/kg) for RBC and WBC when compared to control. There was no significant (P>0.05) differences in the means of other haematological parameters in the extract treated groups compared to control. The extract caused significant (P<0.05-0.01) increases in the level of serum total protein, ALT, ALP, total bilirubin and total cholesterol. The was no significant (P>0.05) changes in the levels of albumin and AST. The extract did not produce any significant (P>0.05) changes in the mean concentrations of urea, creatinine, Na+, K+, and Cl- ions of rats in the extract treated groups compared to that of control. Histopathologic analysis of the vital organs revealed no significant lesions in the brain, liver, kidney, heart, spleen, ovary, and testis. The results suggest the extract to be safe when taken orally though with an insignificant effect on the liver.