Physicochemical Quality and In Vitro Bioequivalence of Amoxicillin Capsules Marketed in Burkina Faso, Africa

Amoxicillin is a penicillin antibiotic widely prescribed to treat many infections. Several brands of oral forms of amoxicillin are available on the local market. The aim of this study was to evaluate the physicochemical quality and in vitro bioequivalence of several brands of amoxicillin capsules (500 mg) marketed in Burkina Faso. Nine different brands of amoxicillin capsules (eight generic and the innovator brand) were purchased from local authorized distributors. Quality control tests (identification, uniformity of weight, disintegration, assay, and dissolution) were performed according to the United States Pharmacopoeia monograph. The comparison of in vitro dissolution profiles was performed in three different pH media (1.2, 4.5, 6.8) using statistical calculations of difference (f(1)) and similarity (f(2)) factors. All brands met USP specifications for physicochemical quality. Amoxicillin content was 104.60-116.04% of the label claim. Mean disintegration time was 6.12-13.44 minutes and dissolution exceeded 80% within 60 minutes. When comparing dissolution profiles, f(1) values > 15 and f(2) values < 50 were obtained for two brands at all three pH levels; these brands cannot be considered interchangeable with the innovator brand. Six out of eight tested generic brands can be considered interchangeable with the innovator product.