Abstract
Dear editor,
The aim of this letter is to highlight the need to strengthen pharmacovigilance towards ensuring that herbal medicines in Nigeria are safe to be taken. Herbal medicines are plant-based products which could be sourced from the roots, stems, barks, or leaves of plants. They are used to treat illnesses or prevent diseases. According to a recent article published in Business Day, it was revealed that many Nigerians now resort to traditional herbal concoctions to meet their healthcare needs without caring for the possible negative implications that may accompany it. 1 Despite the regulatory functions of the regulatory authority in Nigeria and the acceptance of these herbal medicines, issues regarding their safety are still emerging. 2 Due to the weak pharmacovigilance system, adverse reactions of these herbal medicines are largely underreported. 3
Herbal medicines are widely used in Nigeria, yet their safety profile remains poorly monitored. Adverse effects such as skin damage including rashes and allergic reactions have been reported following topical or oral use of certain herbal preparations. More critically, hepatotoxicity and nephrotoxicity have emerged as serious concerns, especially with herbs containing pyrrolizidine alkaloids or improperly dosed mixtures. 4 Drug–herb interactions also pose risks, as herbal products may alter the metabolism of conventional drugs, leading to reduced efficacy or increased toxicity.
These harmful effects are worsened by systemic risks. Many herbal formulations in Nigeria suffer from unclear composition, making it difficult to assess their pharmacological properties or predict adverse reactions. Additionally, contamination with heavy metals, microbes, or adulterants during production or storage is common, posing further health hazards. 4
Herbal medicines, even after approval from NAFDAC, still require intense safety monitoring following distribution, as there might be inconsistencies in the levels of microelements and macroelements used in their production. A study of randomly purchased herbal medicine products showed that many of these products lack the proper concentration levels of microelements and macroelements. 5 Due to the widespread popularity and availability of herbal and traditional medicines, especially in rural and semi-urban settlements, failure to continuously monitor them, even after entering the markets, could pose a health risk to those who use them.
In comparison to conventional medicines, herbal medicines don’t receive enough pharmacovigilance. There is a national belief that herbal medicines have no adverse effects, which is largely false, as research has shown that herbal medicines could have just as many adverse effects as conventional medicines. 6 The safety of herbal medicines on the market could therefore be questionable, as not enough attention has been given to their safety for use.
The National Agency for Food and Drug Administration and Control (NAFDAC) has a crucial role to play in strengthening pharmacovigilance of herbal medicines in Nigeria. First, the agency should enforce existing laws on the manufacture, labelling, and distribution of herbal medicines. This would help strengthen pharmacovigilance of herbal medicines. 7 Also, NAFDAC should dutifully carry out post-marketing surveillance of all regulated herbal medicines.
Findings revealed that NAFDAC is inadequately funded and understaffed and this prevents them from carrying out their duties as expected. 4 The government should provide adequate funding for the agency and hire well-trained staff to help it efficiently carry out its duties towards pharmacovigilance of herbal medicines. The government should also sensitize the general public on the importance of pharmacovigilance and the dangers of consuming herbal medicines which do not meet the standards set by NAFDAC.
Consumers should also help strengthen pharmacovigilance of herbal medicines by reporting adverse drug reactions to healthcare providers who will then report to the National Pharmacovigilance Center. All of these measures would reinforce pharmacovigilance of herbal medicines, ensure patient safety, and preserve the lives of Nigerians.
