Storage implications on the microbiological quality of some locally manufactured pharmaceuticals

Pharmaceutical products non-sterile are expected to  have a minimal microbial load which must not exceed the limits as stated in pharmacopoeia monographs. This study attempted to evaluate storage implications on the microbiological quality of some non-sterile pharmaceutical products manufactured locally in some states in south east Nigeria. Twenty brands of pharmaceutical products comprising 13 tablets, 5 capsules and 2 suspension procured from patent medicine and local drug markets in Aba and Enugu states were stored at room temperature (25oC) for 6 months. Microbial growth was evaluated at 0 and 6 months using standard microbiological procedures including Total aerobic bacteria plate count, isolation, characterization and identification of microbial contaminants. The results from the study showed that 55% and 30% of the pharmaceutical products had bacteria and fungi contamination at 0 month which increased to 70% and  50% at 6 months storage period respectively. Statistical analysis showed there was a significant increase (p < 0.05) in growth of micro-organisms at 6 months for both bacteria and the fungi/moulds (p < 0.05). The isolated bacteria were Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis, Escherichia coli while the fungi include Trichosporonasahii, Curvularia bothriochloae, Candida albicans, Candida parapsilosis. All contaminated samples had microbial counts above the British Pharmacopoeia (BP) acceptabl limit of 103 and 102 CFU/ml for bacteria and fungi respectively. This can be attributed to poor adherence to current Good Manufacturing Practice (cGMP) by the manufacturers. Thus, it is recommended that manufacturers adhere strictly to cGMP and storage conditions stated on these pharmaceutical products followed strictly during distribution and storage to reduce the levels of microbial contamination.