Treatment of Bacterial Vaginosis due to Gardnerella vaginalis
Oral metronidazole 500 mg twice daily for 7 days is the recommended first-line treatment for bacterial vaginosis due to Gardnerella vaginalis, with the highest efficacy rate of 95%. 1, 2
First-Line Treatment Options
- Oral metronidazole 500 mg twice daily for 7 days is the preferred treatment with the highest documented cure rate (95%) 1, 2
- Metronidazole gel 0.75%, one full applicator (5g) intravaginally once daily for 5 days is equally effective as oral therapy but with fewer systemic side effects 1, 2
- Clindamycin cream 2%, one full applicator (5g) intravaginally at bedtime for 7 days is another effective first-line option 1
Alternative Treatment Options
- Oral metronidazole 2g as a single dose has lower efficacy (84% cure rate) compared to the 7-day regimen but may be useful when compliance is a concern 1, 2
- Oral clindamycin 300 mg twice daily for 7 days is an alternative when metronidazole cannot be used 1, 2
- Clindamycin ovules 100g intravaginally once at bedtime for 3 days 1
- Tinidazole has shown efficacy in treating bacterial vaginosis, with regimens of either 2g once daily for 2 days or 1g once daily for 5 days 3
Treatment Considerations
Side Effects and Precautions
- Patients using metronidazole should avoid alcohol during treatment and for 24 hours afterward due to potential disulfiram-like reaction 1, 2
- Clindamycin cream and ovules are oil-based and may weaken latex condoms and diaphragms 1, 2
- Metronidazole may cause gastrointestinal upset and unpleasant taste; intravaginal preparations have fewer systemic side effects 1, 2
Allergy or Intolerance to Metronidazole
- Clindamycin cream or oral clindamycin is preferred for patients with allergy or intolerance to metronidazole 1
- Patients allergic to oral metronidazole should not be administered metronidazole vaginally 1
Special Populations
Pregnancy
- All symptomatic pregnant women should be tested and treated for BV 1, 2
- During first trimester: Clindamycin vaginal cream is preferred due to contraindication of metronidazole 1
- During second and third trimesters: Oral metronidazole can be used 1
- Treatment of BV in high-risk pregnant women (history of preterm delivery) may reduce risk of prematurity 2
Pre-Surgical Considerations
- Before surgical abortion or hysterectomy, screening and treating women with BV is recommended due to increased risk for postoperative infectious complications 1
- Treatment of BV with metronidazole has been shown to substantially reduce post-abortion PID 1
Follow-Up and Recurrence Management
- Follow-up visits are unnecessary if symptoms resolve 1, 2
- Recurrence of BV is common, with up to 50% of women experiencing recurrence within 1 year of treatment 4
- For recurrent BV, an extended course of metronidazole treatment (500 mg twice daily for 10-14 days) is recommended 4
- If the extended course is ineffective, metronidazole vaginal gel 0.75% for 10 days, followed by twice weekly for 3-6 months, is an alternate treatment regimen 4
Management of Sex Partners
- Routine treatment of male sex partners is not recommended as it has not been shown to influence a woman's response to therapy or reduce recurrence rates 1, 2
Comparative Efficacy of Treatment Options
- Clinical trials have shown comparable cure rates between oral metronidazole (84.2%), metronidazole vaginal gel (75.0%), and clindamycin vaginal cream (86.2%) 5
- Patients using intravaginal products reported higher satisfaction with treatment compared to oral therapy 5
- A study comparing clindamycin vaginal cream to oral metronidazole found similar efficacy (97% vs 83% cure rates) 6