An Investigation into The Acute and Subacute Toxicity of Extracts of Cassipourea Flanaganii Stem Bark in vivo

The conventional use of medicinal plants is in part based on the widespread belief that plant crude extracts are non-toxic. In South Africa, traditional preparations of Cassipourea flanaganii used to treat hypermelanosis have accordingly been regarded by many as non-toxic. Whether so, impacts on the potential of bark extracts to be developed as a commercial drug to treat melasma, given their documented capacity to inhibit tyrosinase activity. Our study investigated the acute and subacute toxicity of the methanol extract of C. flanaganii bark in rats. Wistar rats were randomly assigned into different treatment groups. The rats received daily oral gavage of crude extract for acute and sub-acute toxicity tests. Haematological, biomechanical, clinical and histopathology examinations were carried out to evaluate possible toxicity of C. flanaganii. Results were subjected to the Student’s t-test and ANOVA. For both acute and subacute toxicity, there was no statistical difference between groups. There were no clinical or behavioral signs of toxicity observed in the rats. No treatment-related gross pathology lesions as well as no histopathology was observed. The findings of this study demonstrate the absence of acute or subacute toxicity after oral treatment with C. flanaganii bark extracts in Wistar rats at the levels administered.