Microbial contamination of nonsterile pharmaceuticals in public hospital settings

Abstract

Purpose: Contamination of pharmaceuticals with microorganisms irrespective whether they are harmful or nonpathogenic can bring about changes in physicochemical characteristics of the medicines. Although sterility is not a requirement in official compendia for nonsterile pharmaceuticals, bioburdens need to be within acceptable limits. Therefore, this study investigated microbial contamination of 10 nonsterile pharmaceuticals frequently delivered to outpatients by identifying and quantifying microbial contaminants and susceptibility pattern testing on the microbes isolated. Methods: The study was carried out at Amana Municipal Hospital in Dar es Salaam, Tanzania. The protocol for the study involved structured selection of representative tablets, syrups, and capsules from the hospital’s outpatient pharmacy. Constitutive microorganisms were elaborated and enumerated using standard microbiologic procedures. Results: Results showed that 50% of all tested products were heavily contaminated, and the predominant contaminants comprised Klebsiella, Bacillus, and Candida species. Furthermore, the results showed that the isolated Bacillus and Klebsiella species were resistant to Augmentin ® and cloxacillin. The differences in means for cfu/mL and zones of inhibition among the microorganisms isolated were considered significant at P , 0.05. Conclusion: The nonsterile pharmaceuticals were presumably microbiologically contaminated due to poor handling during dispensing, repackaging, and/or nonadherence to good manufacturing practice. Therefore, training and educating the dispensers, as well as patients, on the proper handling and use of medicines cannot be overemphasized, because these are key aspects in controlling cross-contamination of medicines.