Stability Assessment of Extemporaneous Captopril Oral Suspension

Abstract

The aim of this study was to test the stability of extemporaneous captopril oral suspension (1 mg/ml) stored in light-resistant containers. Methods: The physical and chemical stability was assessed in those suspension stored at room temperature (25-28°C) compared to those at the refrigerated temperature (2-8°C). The samples were tested on day 0, 7, 14, 21, 28. Results: The physical characteristics including color, sedimentation and redispersibility of captopril oral suspension were unchanged in all conditions through day 28. The chemical characteristics were measured by pH alteration and the remaining drug content analyzed by reversed phase HPLC. The acceptable range of remaining drug content, based on USP criteria, was 90-110% of the initial content. At room temperature (25-28°C), remaining drug content in suspension was out of the acceptable range. At the refrigerated temperature (2-8°C), remaining drug content in suspension stored was in the acceptable range (90-110%) through 14 days.The pH of extemporaneous captopril oral suspension was found to be less than 4. Conclusion: At the refrigerated temperature (2-8°C), extemporaneous captopril oral suspension was stable for 14 days that remaining drug content was in the acceptable range. The result from this research can help hospital pharmacists to effi ciently assign the shelf life and storage conditions of extemporaneous captopril oral suspension.