Stability and In Vitro Dissolution Studies of Metronidazole Tablets and Infusions

The aim of this study was to compare metronidazole tablets (500 mg) and infusions (500 mg/100 mL) obtained from Saudi and Egyptian suppliers. Evaluation of the tablets included weight variation, hardness, friability, drug content, disintegration time, and dissolution profiles. Stability of the tablets in their original packages after 3-month storage at various temperatures (75% relative humidity) was evaluated, and degradation kinetics was determined. The infusion solutions underwent accelerated stability testing. The Q10 method was used to estimate the shelf life of metronidazole infusions at room temperatures (75% relative humidity) of various climates. Results revealed that all tablets complied with USP specifications, and degradation was slowest at room temperature (20 °C). The mechanism of drug release for all tablets at all temperatures conformed to the Korsmeyer–Peppas model. Metronidazole intravenous infusion solutions stored at 40 °C or 50 °C for 90 days exhibited good stability. The studied Saudi infusion brand is more stable than Egyptian one. The metronidazole tablets and infusion solutions complied with USP specifications and showed similar results in quality control testing. Standard quality control measures should be maintained to ensure safety and efficacy of drug products, especially in climates with extreme temperatures.