Comparison of Oral and Vaginal Metronidazole Therapy for Nonspecific Bacterial Vaginosis

Abstract

A prospective, randomized, nonblind study was performed to compare the efficacy of a 7-day vaginal regimen with 500 mg metronidazole (Flagyl®) once a day and that of oral treatment with 400 mg metronidazole twice daily for 7 days in the treatment of nonspecific bacterial vaginosis. No treatment was given to the sexual partners and there was no restriction of sexual intercourse. 38 women completed the study and at follow-up after 4 weeks, women receiving vaginal therapy had a cure rate of 79% compared with 74% in the women on oral therapy. Cure rates were lower among users of an intrauterine contraceptive device (57 versus 88% among nonusers). The occurrence of lactate-producing bacteria (lacto-bacilli and aerobic streptococci) in the vagina was significantly higher in women after vaginal compared with oral therapy. Gardnerella vaginlis was isolated in 58% of the women after vaginal and in 44% of the women after oral treatment. It is concluded that vaginal application of 500 mg metronidazole daily for 7 days is equally effective as oral administration in the treatment of bacterial vaginosis.

Could Bacterial Vaginosis Be Due to the Competitive Suppression of Lactobacilli by Aerobic Microorganisms?

“…This is to some extent remarkable although not clinically acceptable, par ticularly since metronidazole has given cure rates of about 80% in our hands employing identical criteria [3][4][5][6]. Of course, the present study was not designed to define treat ment efficacy with this drug, but it may be of interest that in a previous study [3] treatment with three different vagi nal preparations other than metronidazole cured only 5 out of 43 patients.…”

“…The change of species from time to time within the same individual showed no systematic pattern. Of the 14 symptomatic patients, 6 were not cured by the treatment, whereas 2 were partly cured (only 2 of the BV criteria present) at both posttreatment visits. Thus, 8 of the 14 patients were cured using the same criteria as in our previous studies.…”

“…Colonization with lactobacilli capable of hydrogen per oxide production [16,17] with BV. This prompted us to reexamine our protocols of all the cases reported upon previously [3][4][5][6], Among those lactobacilli recognized to produce HyCb [15,16], 15 iso lates of L. jensenii were found in women without symp toms and only 1 in a woman with BV. L. rogosae was the second most common with 10 isolates in healthy versus 2 in symptomatic women.…”

Systemic Concentrations of Metronidazole and Its Main Metabolites after Intravenous Oral and Vaginal Administration

“…Vaginal use of metronidazole has been found to be equally effective as oral adminis tration in cases of nonspecific bacterial vagi nosis [8]. As this disorder is considered to represent a disturbance of the vaginal eco system rather than an infection [4,21], vagi nal treatment would be preferable, reducing the risk of general side effects.…”

“…Many reports have claimed that BV is an expres sion of a disturbed vaginal ecology with loss of the natural predominance of lactobacilli rather than an infection with pathogenic mi croorganisms [4][5][6][7], With this in mind it would be superfluous to prescribe potent an tibiotics orally for longer or shorter periods even with a relatively innocent drug. Conse quently, treatment with vaginal tablets of metronidazole has been suggested and found to have equal clinical efficacy as oral treat ment [8].…”