Analysis of Drug Contents of Cefotaxime Formulations Available in the Local Market and the Effect of Storage Conditions

Background: Low quality antimicrobial drugs represent a world-wide problem. Beta-lactams are the main types of antimicrobials found to be substandard or counterfeit. Environmental conditions can play an important role in maintaining drug safety and quality . Aim: To investigate whether the pharmaceutical formulations of cefotaxime, available in the local drug market, contain appropriate amounts of the active ingredients, and how their contents are changed after being exposed to different storage conditions. Methods: Five brand names of cefotaxime vials available in authorized pharmacies in the local drug market, are selected. Drug contents were measured by HPLC (Agilent, UK) using C18 column. Other tests performed include mass uniformity (weight) test, pH of reconstituted solution, identification of impurities, and color of solid dosage forms. Samples were re-analyzed after being exposed to different temperature and humidity levels for 30 days . Results: No substandard and/or counterfeit drugs were found among the tested samples of cefotaxime. The amount of drugs of all tested samples was more than 90% of the labeled one. Tested samples of the drug were stable when stored at a temperature of 35 C˚ for 30 days. When they were stored at temperature of 50 C˚ for 30 days, part of the active ingredients was lost which reached up to 7.4%, with variation between the 5 brands tested. This caused the active ingredients in two brands to fall below the acceptable 90% of the labeled amount. The effect of humidity on the stability of collected samples of different packaged brands of cefotaxime was insignificant . Conclusion: The finding that none of the 5 brands of cefotaxime are of low quality is reassuring and can give the treating physician the choice among different brands of these drugs according to price and availability. Care should be taken in storing or transporting these drugs at high (50 C˚) temperature.