Assessment of the pharmaceutical quality of various brands of omeprazole capsules

Abstract

Introduction: Omeprazole is a first-line therapy drug for the treatment of peptic ulcer disease. The availability of numerous generic brands in the market raises doubts about their quality. Purpose: This study aimed to assess the pharmaceutical quality of various brands of omeprazole capsules marketed in three states of southern Nigeria. Methods: Organoleptic and physicochemical properties of ten (10) generic brands of omeprazole capsules were assessed according to official and unofficial standards. Quality assurance tests such as weight uniformity, disintegration time and drug content assay were carried out. The dissolution test was done in a double dissolution medium consisting of 0.1 N HCl for 1.0 h and phosphate buffer pH 6.8 for 2.0 h. Results: Capsules tested were suitably packaged with shells containing evenly coloured white pellets. All capsules were slightly soluble in water, sparingly soluble in ethanol and readily dissolved in alkaline medium. The 10 brands tested met the British Pharmacopeia (BP) specification for weight uniformity. All capsules had drug content within 90 - 110% and an average disintegration time of less than 15 min. All brands retained the drug in acid medium for 1 hour but released more than 75% within 40 min in phosphate buffer pH 6.8. Conclusion: Brands of omeprazole capsules passed Pharmacopeia tests, exhibited similar in vitro drug release profiles and may therefore be used interchangeably for the treatment of peptic ulcer. The study also showed that almost all brands of omeprazole capsules available in Nigeria are imported, hence the need arises for regular post-clinical analysis of imported drugs. Keywords: Omeprazole, generic brands, quality, analysis