Long-term suppressive therapy with metronidazole in bacterial vaginosis

Treatment with a gel containing metronidazole significantly reduces the frequency of exacerbations in patients with bacterial vaginosis. To evaluate the efficacy of long-term suppressive therapy for bacterial vaginosis with 0.75% metronidazole gel, a prospective multicenter study was conducted. The treatment results of 112 women were analyzed. First, the patients used the gel daily for 10 days, then in the suppressive treatment phase, the gel with metronidazole or a placebo was applied twice a week for 16 weeks.

All patients showed a response to the initial 10-day treatment with 0.75% metronidazole gel. During the second phase of treatment, an exacerbation occurred in 13 (25.5%) women in the metronidazole group and 26 (59.1%) among those receiving placebo (modified analysis in the population of patients to be treated ; relative risk [RR] 0.43; confidence interval [CI] 0.25-0.73; p = 0.001). During the 28 weeks of the follow-up period, relapses occurred in 51% of patients receiving active treatment and 75% of women in the placebo group (RR 0.68; CI 0.49-0.93; p = 0 , 02). The probability of recovery at the end of treatment was 70% in women in the first group and 39% in the placebo group. The corresponding indicators decreased to 34% and 18% by the 28th week of the follow-up period.

Adverse reactions were seen much more often in the active therapy group (82.4% vs 61.4%). Thus, 43.1% of women who used metronidazole developed vaginal candidiasis, while in the control group, candidiasis was observed in 20.5% of patients (p = 0.02).

Thus, long-term suppressive therapy with 0.75% metronidazole gel 2 times a week leads to a significant reduction in the frequency of relapse of bacterial vaginosis, however, it is often complicated by secondary vaginal candidiasis.