Treatment of bacterial vaginosis

Treatment of first choice for Bacterial vaginosis/Gardnerella vaginalis is metronidazole e.g. 400-500mg twice daily for five to seven days (1).

• for the treatment of bacterial vaginosis (BV), the recommended first line options are 400 mg twice daily oral metronidazole for 5 to 7 days, 0.75% metronidazole vaginal gel for 5 days or 2% clindamycin vaginal cream for 7 days (2)
  • Public Health England guidance states antibiotic options as:
    • oral metronidazole 400mg BD for 7 days; OR
    • oral metronidazole 2000mg stat; OR
    • metronidazole 0.75% vaginal gel 5g applicator at night for 5 nights OR
    • clindamycin 2% cream 5g applicator at night for 7 nights
      
      
  • dequalinium may be a suitable alternative treatment if:
    • women cannot tolerate metronidazole or clindamycin, or in other circumstances where those treatments are not suitable e.g. women with inflammatory bowel disease, or antibiotic-associated colitis where clindamycin is contraindicated
    • in situations where fewer treatments are available due to interactions or allergies, e.g. in pregnancy
    • where it would be beneficial to avoid use of an antibiotic (according to local specialist opinion, metronidazole resistance and clindamycin resistance is an increasing but under-recognised problem largely because women with BV are not tested for resistance)

Other treatment regimes that have been shown to be effective include tetracycline and douching therapy with povidone-iodine.

Bacterial vaginosis in pregnancy (3):

• antibiotic treatment can eradicate bacterial vaginosis in pregnancy
• this particular review however provides little evidence that screening and treating all pregnant women with asymptomatic bacterial vaginosis will prevent preterm birth and its consequences
• for women with a previous preterm birth, there is some suggestion that treatment of bacterial vaginosis may reduce the risk of preterm prelabour rupture of membranes and low birthweight
• antibiotic treatment during pregnancy (4):
  • standard treatment in the UK is oral metronidazole 400mg twice a day for five to seven days (1,2,4,8)
    • there are no reports of an increase in birth defects with the use of metronidazole during pregnancy - however, it is better to avoid its use in the first trimester, and recommendations from some experts suggest delaying breast-feeding until 24 hours after completing therapy
      
      
  • topical clindamycin is an alternative treatment option
    • Clindamycin 2% cream at night for 7 days (5)
  • dequalinium is another alternative to metronidazole (2)

Treatment of male sexual partner(7):

• an open label RCT (164 couples in a monogamous relationship) found antimicrobial treatment of the male partner combined with first line antimicrobials for the woman reduced recurrence at 12 weeks vs treatment of the woman alone (35% vs 63%,-2.6 recurrences/person/year p<0.001)
  • addition of combined oral and topical antimicrobial therapy for male partners to treatment of women for bacterial vaginosis resulted in a lower rate of recurrence of bacterial vaginosis within 12 weeks than standard care
  • antimicrobial treatment for the male partner was metronidazole 400 mg oral tablets and 2% clindamycin cream applied to penile skin, both twice daily for 7 days

The summary of product characteristics must be consulted before prescribing any of the drugs mentioned.

Key points (8):

• oral metronidazole is as effective as topical treatment, and is cheaper
  • 7 days results in fewer relapses than 2g stat at 4 weeks
• pregnant/breastfeeding: avoid 2g dose of metronidazole

Notes:

• dequalinium chloride is a quaternary ammonium compound that acts as a surface antiseptic agent
  • in 2015, a vaginal tablet formulation was licensed for the treatment of bacterial vaginosis
  • acts on bacterial cells to increase cell permeability and decrease bacterial enzyme activity leading to cell death
  • recommended dose and course of treatment is one vaginal tablet daily for six days. Tablets should be inserted deep within the vagina in the evenings before retiring
    
    
• bacterial vaginosis
  • characterized by an overgrowth of predominantly anaerobic organisms (such as Gardnerella vaginalis, Prevotella species, Mycoplasma hominis, and Mobiluncus species) and a loss of lactobacilli

Reference:

• (1) Drug and Therapeutics Bulletin 1998; 36 (5): 33-5.
• (2) Midlands Therapeutics Review and Advisory Committe (MTRAC (September 2018)). Considerations for Commissioners Dequalinium chloride
• (3) Cochrane Database Syst Rev. 2005 Jan 25;(1):CD00026
• (4) Prescriber 2005; 16(6):14-24.
• (5) Coventry PCT (November 2007). Antibiotic guidelines community.
• (6) Larsson PG, Forsum U. Bacterial vaginosis a disturbed bacterial flora and treatment enigma. Review article APMIS 2005 ; 113 (5):305-316.
• (7) Vodstrcil LA et al. Male-Partner Treatment to Prevent Recurrence of Bacterial Vaginosis. N Engl J Med 2025;392:947-957
• (8) Public Health England (June 2021). Managing common infections: guidance for primary care