Are Nigerian-market Amlodipine 10 mg tablets interchangeable? Evidence from in-vitro quality tests

Abstract

Amlodipine is a widely used antihypertensive medication in Nigeria, with multiple generic brands available in the market. Ensuring the quality and therapeutic equivalence of these generics is crucial for patient safety and treatment efficacy. This study evaluated the physicochemical properties and dissolution profiles of thirteen brands of amlodipine besylate 10 mg tablets marketed in Nigeria. The brands were assessed for compliance with British Pharmacopoeia standards, and their dissolution profiles were compared using model-independent parameters (f1 and f2). Most brands met the required specifications for weight variation, friability, assay, and dissolution. However, notable variability was observed in dissolution behavior, with some brands exhibiting borderline or non-similar profiles compared to the innovator brand. The f1 and f2 values indicated that seven brands were similar to the innovator, while three brands failed to show similarity. The study highlights the need for rigorous regulatory oversight to ensure that only consistently compliant products remain in circulation.