Aims of the study: Gynura procumbens (Merr.), which is known as "Sambung nyawa", is widely used in South East Asian countries in the traditional treatment of many ailments. However, there is little toxicological information available regarding safety following repeated exposure. The present investigation describes the toxicity of a methanol extract of Gynura procumbens leaves in rats.
Materials and methods: For acute toxicity studies, a methanol extract of Gynura procumbens was orally administered to Sprague-Dawley rats (female and male) at a dose range of 1000-5000 mg/kg. For sub-chronic toxicity studies, the rats were orally administered the methanol extract of Gynura procumbens at the doses of 125, 250, and 500 mg/(kg day) for a period of 13 weeks. The animals were sacrificed, followed by examination of their organs and blood serum.
Results and conclusions: Administration of the methanol extract from Gynura procumbens leaves at 1000-5000 mg/kg did not produce mortality or significant changes in the general behaviour, body weight, or organ gross appearance of rats. There were no significant differences in the general condition, growth, organ weights, haematological parameters, clinical chemistry values, or gross and microscopic appearance of the organs from the treatment groups as compared to the control group. Therefore, the NOAEL for the Gynura procumbens methanol extract is 500 mg/(kg day) administered orally for 13 weeks.