Treatment for Bacterial Vaginosis (BV)
Metronidazole 500 mg orally twice daily for 7 days is the recommended first-line treatment for bacterial vaginosis in non-pregnant women. 1
Treatment Options for Non-Pregnant Women
The CDC recommends three equally effective first-line treatment options for non-pregnant women with BV:
- Metronidazole 500 mg orally twice daily for 7 days
- Metronidazole gel 0.75%, one full applicator (5 g) intravaginally once daily for 5 days
- Clindamycin cream 2%, one full applicator (5 g) intravaginally at bedtime for 7 days 1
Alternative regimens include:
- Clindamycin 300 mg orally twice daily for 7 days
- Clindamycin ovules 100 g intravaginally once at bedtime for 3 days 1
- Tinidazole 2 g once daily for 2 days or 1 g once daily for 5 days 2
Treatment During Pregnancy
Treatment recommendations differ by trimester:
- First trimester: Clindamycin vaginal cream is the preferred treatment as metronidazole is contraindicated 1
- Second and third trimesters:
- Preferred: Vaginal metronidazole gel or clindamycin cream
- Alternative: Metronidazole 500 mg orally twice daily for 7 days or 250 mg orally three times daily for 7 days 1
Diagnosis of BV
BV diagnosis requires confirming at least three of the following clinical criteria:
- Homogeneous, white discharge adhering to vaginal walls
- Presence of clue cells on microscopic examination
- Vaginal fluid pH greater than 4.5
- Fishy odor of vaginal discharge before or after addition of 10% KOH (positive whiff test) 1
Important Considerations
- Alcohol avoidance: Patients should avoid alcohol during metronidazole treatment and for 24 hours afterward to prevent disulfiram-like reactions 1
- Breastfeeding: Metronidazole is secreted in human milk, so a decision should be made whether to discontinue nursing or the drug 1
- Partner treatment: Routine treatment of sex partners is not recommended as clinical trials indicate that partner treatment does not affect treatment response or likelihood of recurrence 1
Management of Recurrent BV
Recurrence is common, with 50-80% of women experiencing recurrence within a year of treatment 1, 3. For recurrent BV:
- Use an extended course of metronidazole (500 mg twice daily for 10-14 days)
- If ineffective, consider metronidazole vaginal gel 0.75% for 10 days, followed by twice weekly for 3-6 months 4
Follow-up Recommendations
- Routine follow-up is unnecessary if symptoms resolve in non-pregnant women 1
- For high-risk pregnant women, follow-up evaluation 1 month after treatment completion is recommended 1
Advantages of Vaginal vs. Oral Administration
Intravaginal metronidazole is as effective as oral administration but with significantly fewer side effects:
- Nausea: 10.2% (vaginal) vs. 30.4% (oral)
- Abdominal pain: 16.8% (vaginal) vs. 31.9% (oral)
- Metallic taste: 8.8% (vaginal) vs. 17.9% (oral) 5
This reduced side effect profile may improve patient compliance and satisfaction with treatment.