Regulation of Herbal Medicine Manufacturing: Microbiological Compliance Assessment of NAFDAC-Registered Manufacturers in Onitsha, Anambra State

Herbal medicines occupy a significant position in Nigeria's health product market, yet the microbiological compliance of manufacturers registered with NAFDAC with pharmacopoeial quality standards requires systematic evaluation. This study assessed microbiological compliance among NAFDAC-registered herbal medicine manufacturers in Onitsha, Anambra State, South East Nigeria. Twenty manufacturers were visited for facility audit and product sample collection. Twelve products per manufacturer were sampled covering tablets, capsules, liquid preparations, and powders. Microbiological testing followed the BP/USP non-sterile products testing protocol, including TAMC, TYMC, and specific organism testing. Manufacturing facility hygiene, water quality systems, and quality control laboratory availability were assessed against GMP requirements. Results showed that 45 percent of finished product samples failed one or more microbiological limits. E. coli was detected in 15 percent of liquid preparations, and aflatoxin-producing Aspergillus species were recovered from 22 percent of powdered products. Sixty percent of facilities lacked dedicated quality control laboratories, relying on external testing that was infrequent and poorly documented. Facility water quality testing was absent in 70 percent of manufacturers. These findings reflect the widespread microbiological non-compliance among registered herbal medicine manufacturers in the study area and underscore the need for NAFDAC to adopt risk-based inspection frequency and capacity-building support tailored to herbal medicine GMP requirements. Keywords: herbal medicine, microbiological compliance, NAFDAC, GMP, Onitsha.