Safety pharmacology of herbal medicines in South Africa

Abstract

The use of herbal medicine for treating various ailments has a deep history in South African traditional medicine. South Africa has a rich floral biodiversity which has been exploited for centuries mainly for day-to-day healthcare needs and food security. Almost 70% of South Africans rely on traditional medicine (TM) for their primary healthcare needs. There is a misconception that “natural” means safe from toxicity. However, a number of herbal medicines have been reported for severe side effects such as hepatotoxicity, renal failure and allergic reactions. The safety of TM is now a major concern for both health authorities and the general public. Safety pharmacology of herbal medicines is intended to detect potential adverse functional effects on various organ systems. The proposed criteria of safety pharmacology for herbal medicine should be the same as for Western drugs. The 10 most frequently used South African medicinal plants will be selected for this study. The Irwin test will be conducted to detect any untoward toxicity using Sprague-Dawley rats (n = 3). Aqueous extracts of the selected plants will be administered to the animals by oral gavage and the control group will receive solvent blank. The administered doses will exceed the therapeutic range just enough to produce moderate adverse effect. Telemetered rats will be used to assess the effects the selected herbal medicines will have on the core battery such as the cardiovascular, respiratory and CNS systems. All the experiments will follow the ARRIVE guidelines. Behaviours and clinical signals observed in the Irwin test, as well as data from telemetered rats will be used to identify the principle effects of all the test substances. South Africa is at the verge of incorporating traditional medicine into the mainstream healthcare system, robust safety pharmacology studies will ensure the safe of use of herbal medicine