Quality assessment of different brands of diclofenac tablets marketed in Ilorin metropolis: a pharmaceutical and public health perspective.

Abstract

Background: The quality of a medicinal product is an important factor for its safety and efficacy. Poor-quality medicines are a major impediment to improvements in public health. This study assessed the pharmaceutical quality of different brands of diclofenac (DCF) tablets in Ilorin metropolis. Methods: Four randomly selected brands of diclofenac potassium tablets (coded: DCF-A, DCF-B, DCF-C and DCF-D) were obtained from pharmaceutical outlets, and quality parameters were evaluated according to Pharmacopeial methods. The potency of tablets was determined spectrophotometrically based on the measurement of maximum absorbance at a wavelength of 276 nm in doubly distilled water. Results: Method validation according to the International Council for Harmonization guidelines showed acceptable sensitivity (limit of detection of 0.3886 μg/mL and limit of quanti􀃶cation of 1.1775 μg/mL), precision (% relative standard deviation range of 0.72 – 1.54), accuracy (% recovery range of 98.9 – 101.3). Average contents of active diclofenac were 45, 98, 103 and 105% for DCF-A, DCF-B, DCF-C and DCF-D respectively. DCF-A brand was not only substandard but falsi􀃶ed based on British Pharmacopoeia potency speci􀃶cation range of 95 – 105%. Conclusion: A substandard and falsi􀃶ed brand of diclofenac tablets was detected. Drug regulatory authority must ensure periodic post-registration surveillance of licensed pharmaceutical products marketed in the country to secure the health and safety of the populace.