Low-dose secnidazole in the treatment of bacterial vaginosis

To determine whether bacterial vaginosis could be cured with a single 1-g oral dose of secnidazole.

A total of 80 women were recruited at the outpatient gynecologic clinic of Manuel Noriega Hospital, Maracaibo, Venezuela. Diagnosis and patient enrollment were based on the Amsel criteria. The participants were randomized to 2 groups. In group 1 (n=44) participants received a single 1-g oral dose and in group 2 (n=32) participants received a single 2-g oral dose of secnidazole. Clinical cure was defined as the absence of the characteristic symptoms (a bad odor and a grossly abnormal discharge) and at least 2 of the following: vaginal pH less than 4.5, no fish odor on addition of KOH, and no Gardnerella vaginalis or clue cells on wet-mount examination. Cytologic cure was defined as an absence of G. vaginalis on a Papanicolaou (Pap) smear.

Clinical cure was experienced by 95.5% of the women who received the 1-g oral dose and by 97.4% of the women who received the 2-g oral dose of secnidazole. There was no significant difference between the groups in the clinical resolution of bacterial vaginosis. Following treatment, results were negative for G. vaginalis in 94.7% of the women. In group 1, 41 women (93.2%), and in group 2, 31 women (96.9%) had cytologic cure. The Pap smear revealed G. vaginalis in 3 of the women in group 1 and 1 of the women in group 2 (P=0.47). Twenty-seven women (35.5%) reported mild side effects. More women had adverse effects in group 1 (n=16) than in group 2 (n=11) but this difference was not statistically significant.

This clinical study showed that a single 1-g oral dose of secnidazole is effective to cure bacterial vaginosis associated with G. vaginalis.