Comparative Toxicity Studies of Rauwolfia vomitoria Leaf and Root Extracts in Wistar Rats

Aim: Rauwolfia vomitoria Afzel (Apocynaceae) is used in the African traditional medical practice for the management of various diseases such as a cough, malaria and as an anti-psychotic. The present study investigates the toxicological potential of the administration of the leaf and root extracts of Rauwolfia vomitoria on the brain, kidney and liver of male Wistar rats.

Materials and Methods: The toxicity study was carried out by Lorke’s method. For the acute study, thirteen groups of 5 rats each were orally administered 10, 100 and 1000 mg/kg of aqueous and ethanol extracts of leaf and root of R. vomitoria. Mortality was recorded after 24h. For the subacute, thirteen groups of five rats each were orally given doses of 1600, 2900 and 5000 mg aqueous and ethanol extracts of leaf and root of R. vomitoria. Observation continued for 2weeks after administration to check for any mortality arising from delayed toxicity. In the end, surviving animals were sacrificed and pathological changes were observed.

Results: There was a dose-dependent increase in the liver enzymes in the subchronic and subacute. Histological studies reveal an area of inflammations in the liver subacute study. No significant differences were noticed in the concentration of urea, creatinine and the electrolytes among the various group and control. There were no marked cellular changes in the kidney tissue. Convulsion was observed in a subacute study among the animals at a high dose of 5000 mg of the root extract.

Conclusion: The use of the leaf and root extracts of Rauwolfia vomitoria is safe to the liver, kidney and brain when used at low doses over a long time but harmful when used at high doses over a short time.