Acute and sub-acute toxicity of aqueous extract of aerial parts of Caralluma dalzielii N. E. Brown in mice and rats.

Caralluma dalzielii N. E. Brown (Asclepiadaceae) is a cactus-like shaped shrub widely used in traditional medicine for the treatment of rheumatoid arthritis, diabetes, infertility and impotence. The present study evaluated the potential toxicity of aqueous extract of aerial parts of Caralluma dalzielii (AECD) through acute and sub-acute oral administration in mice and rats. During acute toxicity study, female mice and rats were orally administered with AECD at single doses of 175, 500 and 2000 mg/kg according to OECD Guidelines 425. Sub-acute toxicity of AECD (150, 300 and 600 mg/kg p.o) was studied by daily dosing of Wistar rats of both sexes for 28 days. The acute toxicity study revealed no lethal effects and behavioural signs of toxicity at the tested doses indicating that LD₅₀ is greater than 2000 mg/kg. In sub-acute study, a significant reduction in the body weight (p < 0.05), feed and water (p < 0.001) intake of the rats were observed. A significant (p < 0.05) increase in lymphocytes, mean platelet volume counts and alanine aminotransferase were also observed. Histopathological analysis showed mild liver cell distortion in female rats treated at 600 mg/kg of AECD. These results show low toxicity of AECD on short-term use and liver toxicity on long-term use.