Comparative Evaluation of Antimalarial Drug Content in Products Sold by Patent Medicine Vendors in Sokoto State

Patent medicine vendors represent a critical point of access for antimalarial treatment in rural and semi-urban areas of North West Nigeria where formal healthcare infrastructure is limited. The quality of antimalarial products sold through this distribution channel directly influences treatment outcomes and the risk of drug-resistant parasite development. This study evaluated the content of active pharmaceutical ingredients in fifteen antimalarial drug products, including artemether-lumefantrine, chloroquine, and artesunate tablets, purchased from patent medicine vendors in Sokoto State. Products were analysed by High-Performance Liquid Chromatography using validated methods with certified reference standards. Dissolution testing was also performed using USP compendial methods. Only nine of the fifteen products met the pharmacopoeial acceptance criteria for API content of 90 to 110% of label claim. Three artemether-lumefantrine brands contained less than 80% of declared artemether content. Dissolution testing further confirmed inadequate drug release for two products. Counterfeit features were noted on one chloroquine product based on packaging inconsistencies. These findings highlight significant quality deficiencies in antimalarial medicines available through informal retail outlets in Sokoto State. Enhanced post-market surveillance and stricter vendor licensing requirements by NAFDAC and the state health authorities are urgently recommended. Keywords: antimalarial drugs, patent medicine vendors, HPLC, Sokoto State, drug quality.