Microbial Load Assessment of Commonly Dispensed Liquid Oral Preparations in Community Pharmacies in Ibadan, Oyo State

Liquid oral pharmaceutical preparations are among the most widely dispensed medications in community pharmacies across Nigeria, yet their microbiological integrity during open shelf life has received limited attention. This study assessed the microbial load of ten commonly dispensed liquid oral preparations obtained from 30 registered community pharmacies in Ibadan, Oyo State, South West Nigeria. Samples were collected at three stages: at dispensing, after 7 days, and after 14 days of simulated patient use. Total aerobic plate count, yeast and mold count, and screening for specific pathogens including E. coli, Salmonella, and Pseudomonas aeruginosa were carried out using USP compendial microbiological methods. Results showed progressive increases in microbial counts across all products with time, with 60 percent of samples exceeding USP microbial limits by day 14. Suspensions with broken seals and syrups stored at ambient room temperatures showed the highest contamination rates. Pseudomonas aeruginosa was the most frequently recovered contaminant, detected in 18 percent of post-dispensing samples. These findings point to inadequate patient counseling on storage conditions and a lack of standardized post-dispensing microbiological guidelines in Nigerian pharmacy practice. The study recommends the development of evidence-based beyond-use dating policies for liquid oral medications and routine microbiological auditing of dispensed products. Keywords: liquid oral preparations, microbial contamination, community pharmacy, Ibadan, beyond-use dating.