Assessment of Quality Control Practices in Locally Formulated Herbal Supplements Registered with NAFDAC in South East Nigeria

The herbal supplement market in Nigeria has expanded rapidly in recent years, but concerns persist about inconsistent quality, adulteration, and inaccurate labelling of products, even among registered formulations. This study assesses quality control practices in the manufacture of locally formulated herbal supplements registered with NAFDAC, focusing on companies in Enugu and Imo States, South East Nigeria. An audit of twelve herbal supplement manufacturers was conducted using a quality assurance evaluation tool aligned with WHO Guidelines for Good Manufacturing Practices for Herbal Medicines. Parameters assessed include raw material sourcing and quality testing, in-process quality controls, finished product testing capability, batch record systems, and personnel training. Selected product samples were collected and analysed for heavy metal contamination, microbial load, identification of claimed plant species by thin-layer chromatography, and label claim verification for active constituents. Audit results reveal that ten of twelve manufacturers lacked validated in-house analytical methods for active constituent quantification. Six facilities had no formal system for testing incoming raw plant materials for identity or contamination. Heavy metal analysis identified lead exceeding WHO limits in samples from two manufacturers. Microbial contamination exceeded acceptable limits in three of twelve product batches tested. The study recommends NAFDAC-enforced implementation of Good Manufacturing Practice guidelines, investment in industry laboratory infrastructure, and a mandatory pre-market active constituent verification protocol for herbal supplement registration. Keywords: herbal supplements, quality control, NAFDAC, Good Manufacturing Practice, South East Nigeria