Antimicrobial treatments for bacterial vaginosis (BV) are effective, but taking lactobacillus tablets alongside metronidazole antibiotic therapy increases effectiveness over taking this antibiotic alone, according to a Cochrane Systematic Review. The researchers also concluded that intravaginal lactobacillus was as effective as oral metronidazole, although they did note unexplained drop-outs from the trials.
BV is a very common vaginal infection. Traditionally, antibiotics in tablet or gel form have been given to treat the disease, but some have unpleasant side effects. BV is usually a mild disease and can pass unnoticed but is associated with an increased risk of HIV transmission.
"Treating BV could help reduce susceptibility of women to HIV. Therefore it is important, particularly in the developing world, to establish the most effective and appropriate forms of treatment," says lead researcher Oyinlola Oduyebo, of the Department of Medical Microbiology and Parasitology at the University of Lagos in Lagos Nigeria.
The researchers reviewed 24 trials involving 4,422 people. The antibiotics clindamycin and metronidazole both cured BV in over 90% of cases within two to three weeks, although there was a high rate of relapse. Side effects of metronidazole included nausea and a metallic taste in the mouth. However, it is the cheaper option and therefore likely to remain the most widely used in developing countries. Lactobacillus probiotic taken alongside metronidazole and taken intravaginally both showed significant effectiveness. Hydrogen peroxide and triple sulphonamide cream were not effective.
"There are a range of good treatments for BV, but the high relapse rates require more attention and indicate that we need more research into other agents that can increase their effectiveness," said Oduyebo. "We also need to understand why so many people dropped out of the Lactobacillus trials as this suggests there are unreported adverse effects."