Impact of traditional African medicine on drug metabolism and transport

Introduction: Africa is a continent of rich plant biodiversity with many indigenous plants having a long history of being used for medicinal purposes. A considerable number of patients consult traditional healers in African countries for their primary health-care needs. As Western medicines become more available through governmental programmes to treat diseases such as infections with HIV/AIDS, patients are faced with an increased potential of herb–drug interactions. Areas covered: Several medicinal herbs indigenous to Africa are discussed in terms of their effects on pharmacokinetics of allopathic drugs through modulation of enzymes and active transporters. Clinically relevant herb–drug interactions obtained from in vivo studies are discussed, with data from in vitro studies also included to ensure a complete review. Expert opinion: Traditional herbal medicines are often used under a false sense of security because of the perception that it is safe due to its natural origin. The potential for interactions between herbal and allopathic drugs is often neglected. Data on clinically relevant herb–drug interactions from clinical trials can be used to educate health-care workers and patients, contributing to improved therapeutic outcomes.