Quality Control Analysis of Omeprazole Capsules 20 mg in Pharmacies, Vientiane Capital, Lao PDR

Abstract

Gastric diseases are non-communicable diseases (NCDs) found worldwide, caused by various factors such as poor dietary habits, stress, use of NSAIDs, and Helicobacter pylori infection. Treatment often uses proton pump inhibitors (PPIs), such as omeprazole, to reduce gastric acid secretion. Reports indicate that omeprazole not meeting quality standards has been found in many countries in the ASEAN region, which may result in treatment failure and pose safety risks. In the Lao PDR, omeprazole is distributed under many brand names, both domestically produced and imported, and some products have not yet been registered with the Food and Drug Department. This situation highlights the need to monitor the quality of medicines sold in pharmacies to ensure safety and treatment efficacy. The aim of this study was to assess the quality of Omeprazole capsules 20 mg sold in pharmacies in Vientiane Capital. The study employed the HPLC validation method following ICH guidelines, evaluating linearity, accuracy, and precision. Six samples were collected to examine the uniformity of weight and to perform an assay. The results showed that the HPLC analysis method met ICH guideline requirements, with R² = 0.999, %Recovery 98.40–102.25%, and %RSD 0.02–0.12%. Among the six samples, 2 samples (33.33%) were domestically produced, and 4 samples (66.66%) were imported, with 4 samples not yet registered with the Food and Drug Department. Assay testing according to USP revealed that 3 samples were within the 90–110% range, while 3 samples exceeded 110% (114.45%, 111.96%, and 111.45%). These findings demonstrate that the HPLC analysis method is accurate and precise according to international (ICH) standards, suitable for quality control of omeprazole in laboratories and for pharmaceutical quality assurance. However, some imported omeprazole products that have not yet been registered exceeded the USP limits, highlighting the importance of registration and quality monitoring to ensure medicine safety and efficacy.