Randomized, double-blind, comparative study of oral metronidazole and tinidazole in treatment of bacterial vaginosis

OBJECTIVE: To compare the efficacy and tolerability of oral metronidazole and tinidazole in patients with bacterial vaginosis (BV) using Amsel's criteria. PATIENTS AND METHODS: This was a randomized double-blind study, conducted by the Departments of Pharmacology and Gynecology of a tertiary care teaching hospital. Patients diagnosed with BV received either tablet metronidazole 500 mg twice daily for 5 days or tablet tinidazole 500 mg once daily + one placebo for 5 days and instructed to come for follow-up at the 1(st) week and 4(th) week. They were categorized as cured, partially cured, and not cured based on Amsel's criteria at the end of the study and compared between two groups using Chi-square test. RESULTS: A total 120 women were enrolled in the study, of which 114 completed the study. The treatment arms were comparable. The cure rate with low-dose tinidazole was significantly more compared to metronidazole at 4(th) week (P = 0.0013), but not at 1(st) week (P = 0.242). The adverse drug reactions were less with tinidazole compared to metronidazole. CONCLUSION: Tinidazole at lower dose offers a better efficacy than metronidazole in long-term cure rates and in preventing relapses with better side effect profile.