Metronidazole and Tinidazole: A Battle of safety profile

Abstract- Background: Nitroimidazoles are frequently prescribed to prevent and treat anaerobic infections, distinctly in surgical patients. Both agents exhibit a broad spectrum of activity against gram-positive bacteria, gram- negative bacteria and protozoans. However, their adverse drug reaction profiles differ. This study aims to compare the adverse drug reaction profiles of metronidazole and tinidazole in surgical patients treated for anaerobic infections in the gut and foot. Materials and Methods: A case-control study was conducted in a multi-specialty hospital over a period of five months (September 2023–January 2024). Fifty patients meeting the study criteria were enrolled in the study. Adverse drug reactions were assessed using Naranjo’s and WHO causality assessment scales. Results: 88% of subjects prescribed Metronidazole experienced adverse drug reactions, with constipation being the most prevalent, while only 12% of patients on tinidazole experienced adverse drug reactions. The adverse drug reactions observed with tinidazole were less frequent and less severe compared to those with metronidazole, with statistically significant differences (p < 0.001, Pearson value: 32.05). Conclusion: Among 50 patient’s metronidazole 25 (50%) and tinidazole 25 (50%) the ADR reported among patients receiving tinidazole was less when compared to the patients who were on metronidazole [Tinidazole 3 (12%); Metronidazole 22 (88%). The result was statistically significant as the p-value was less than 0.001 and the Pearson value was found to be 32.05. The research concludes that tinidazole is a safer alternative to metronidazole.