Comparative studies on the microbiological and physical quality of expired and unexpired pediatric syrup

Abstract

Background: The recent increase in the number of cases of contaminated drugs had necessitated the need for research involving microbial contamination and subsequent deterioration of drug quality (Tanko and Antai, 2006). The microbiological and physical quality of selected expired and unexpired pediatric syrups were assessed in selected drug outlet in Owerri Imo state Nigeria.
Aim: this study is aimed at assessing and comparing the quality of expired and unexpired drugs at pharmaceutical outlets at Douglas and Wetheral roads in Owerri, Imo State.
Materials and methods: comparative study on the microbiological and physical quality of unexpired and expired pediatric syrup was carried out in the medical microbiology laboratory using different categories of syrup samples. A total of twenty samples where used in this study, ten syrup in each case, with each syrup having the expired and unexpired form. Different culture media were used for microbial cultivation, The microbiological and physical changes in syrups were observed and assessed. The unexpired syrup sample were found to maintain their original taste, color and viscosity, while having the lowest load of contamination ranging from (Log10 1.53cfu/ml – Log10 1.71cfu/ml) for bacteria and (Log10 0.68cfu/ml – Log₁₀ 1.70cfu/ml) for fungi. While expired syrup sample showed changes in taste, color and viscosity ,with the highest load of contamination ranging from (Log₁₀ 2.25cfu/ml – Log₁₀ 1.79cfu/ml) for bacteria and (Log₁₀ 0.9cfu/ml – Log₁₀ 1.96cfu/ml) for fungi. Microbial analysis on the unexpired syrups revealed the presence of Aspergillus species (3.8%) Candida albican(1.7%),Escherichia coli (5.4%). While Analysis on the expired syrups revealed the increase in the presence of Staphylococcus species (18.0%), Escherichia coli (14.0%), while fungal isolates were Aspergillus species (8.3%), Rhizopus species (0.2%), Candida albican (3.6%)