Recent developments in our understanding of the implications of traditional African medicine on drug metabolism

ABSTRACT

Introduction: The use of traditional herbal medicines has become increasingly popular globally, but in some countries, it is the main or sometimes even the only healthcare service available in the most rural areas. This is especially true for Africa where herbal medicines form a key component of traditional medicinal practices and there is access to a diversity of medicinal plants. Although many benefits have been derived from the use of traditional herbal medicines, many concerns are associated with their use of which herb-drug interactions have been identified to have a rising impact on patient treatment outcome. One type of pharmacokinetic interaction involves the modulation of drug metabolizing enzymes, which may result in enhanced or reduced bioavailability of co-administered drugs.

Areas covered: This review highlights the current information available on drug metabolism-associated information with regards to traditional African medicines related to some of the most prevalent diseases burdening the African continent.

Expert opinion: It is clear from previous studies that enzyme modulation by traditional African medicines plays a significant role in the pharmacokinetics of some co-administered drugs, but more research is needed to provide detailed information on these interactions, specifically for treatment of prevalent diseases such as tuberculosis and hypertension.

KEYWORDS:

• Cytochrome P450
• drug metabolism
• enzyme inhibition
• herb-drug interaction
• traditional African medicine

Article highlights

• Africa has a large diversity of plants and herbal medicines form a key component of traditional medicinal practices.

• Potential of herb-drug interactions is a growing cause for concern, including the potential inhibition of drug metabolizing enzymes which may result in enhanced bioavailability of the co-administered drug.

• There is a lack of in vivo information regarding drug metabolism-associated interactions with regards to traditional African medicines and the treatment of the most prevalent diseases burdening the African continent.

• Intensive herb-drug interaction studies are usually only initiated upon occurrence of serious adverse events or filing of case reports to medical practitioners where patients have experienced serious toxic effects.

• There is a need for effective high throughput in vitro assays for routine screening to identify potentially serious and clinically significant herb-drug interactions.

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Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose

Additional information

Funding

This work was supported by the National Research Foundation (NRF) of South Africa; under Grant numbers 91460 and 98939; and the South African Medical Research Council; under Self-Initiated Research grant.