QUALITY CONTROL ASSESSMENT OF THE COMMERCIALLY AVAILABLE AMLODIPINE TABLET BRANDS IN PORT HARCOURT, NIGERIA

Background: Hypertension remains a major public health challenge in Nigeria and globally, with calcium channel blockers such as amlodipine forming a cornerstone of long-term pharmacotherapy. The therapeutic effectiveness of amlodipine tablets depends on their compliance with established pharmacopeial quality control parameters. Concerns about substandard and falsified medicines in low- and middle-income countries necessitate continuous post-market quality surveillance of commercially available brands. Objectives: This study aimed to assess the quality control parameters and pharmaceutical equivalence of selected commercially available amlodipine tablet brands marketed in Nigeria in order to ascertain their compliance with official specifications. Methods: Multiple brands of amlodipine tablets were procured from registered pharmacies. Standard physicochemical quality control tests were performed in accordance with pharmacopeial guidelines, including visual inspection, weight uniformity, hardness, friability, disintegration time, assay of active pharmaceutical ingredient (API) content using validated analytical methods, and in vitro dissolution studies. The dissolution profiles were evaluated against pharmacopeial acceptance criteria to determine interchangeability and compliance. Results: All evaluated brands complied with official specifications for organoleptic properties and weight uniformity. Most brands met acceptable limits for hardness, friability, and disintegration time. Assay results demonstrated that the API content of the majority of brands fell within the pharmacopeial range (typically 90–110%). Dissolution testing revealed that while several brands achieved the required percentage drug release within the stipulated time, minor variations in release profiles were observed among some brands. Conclusion: The findings indicate that most commercially available amlodipine tablet brands assessed were of acceptable pharmaceutical quality and complied with established standards, supporting their therapeutic interchangeability. Continuous regulatory surveillance remains essential to ensure sustained product quality and patient safety.