INTRODUCTION: CIP, a broad-spectrum antibiotic, is crucial for managing bacterial infections. Its efficacy relies on maintaining high-quality standards, which can be affected by manufacturing, regulatory oversight and storage practices. This study compares the quality of CIP preparations in Vietnam and Nigeria, two nations with contrasting regulatory frameworks, to assess compliance with pharmaceutical standards and identify risks from substandard or falsified medicines. METHODS: A total of 46 CIP preparations were analysed, 20 purchased from 13 vendors in Vietnam and 26 from 13 vendors in Nigeria. Data on vendor qualifications and storage conditions were collected. Antibacterial activity was tested using a modified disk diffusion assay, and content and purity were evaluated via reversed-phase HPLC. RESULTS: Vietnam's drug outlets showed stricter regulation, with 100% registration and 61.5% staffed by Bachelor of Pharmacy holders, compared with only 23.1% in Nigeria. Temperature and humidity monitoring was universal in Vietnam but minimal in Nigeria (23.1% and 15.4%, respectively). Antimicrobial testing confirmed effectiveness for all but one sample (Vietnam), while Nigerian samples had greater variability. Reversed-phase HPLC revealed seven Nigerian samples (26.9%) with <
80% declared CIP content, all from one manufacturer. Median content was 91% in Vietnam and 88% in Nigeria, with most samples meeting purity standards. CONCLUSIONS: The study highlights significant disparities in the regulation, storage practices and quality of CIP between Vietnam and Nigeria. These findings underscore the critical need for improved regulation, monitoring and enforcement in countries with weaker pharmaceutical oversight to ensure drug efficacy and safety.