Empiric Treatment of Vaginitis
The recommended empiric treatment for vaginitis depends on the specific type, with metronidazole 500 mg orally twice daily for 7 days being the first-line treatment for bacterial vaginosis, the most common cause of vaginitis. 1
Types of Vaginitis and Their Treatments
Bacterial Vaginosis (40-50% of cases)
First-line Treatment:
- Metronidazole 500 mg orally twice daily for 7 days 1
Alternative Regimens:
- Metronidazole gel 0.75%, one full applicator (5 g) intravaginally, once daily for 5 days 1
- Clindamycin cream 2%, one full applicator (5 g) intravaginally at bedtime for 7 days 1
- Metronidazole 2 g orally in a single dose (lower efficacy) 1
- Clindamycin 300 mg orally twice daily for 7 days 1
- 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 (shown superior to placebo) 2
Vulvovaginal Candidiasis (20-25% of cases)
Treatment Options:
- Topical azoles (clotrimazole, miconazole) for 7-14 days 3, 4
- Oral fluconazole 150 mg single dose (equally effective as topical therapy) 5, 4
Trichomoniasis (15-20% of cases)
First-line Treatment:
- Metronidazole 2 g orally in a single dose 6
- Metronidazole 500 mg twice daily for 7 days (equally effective, cure rates up to 88%) 6
- Tinidazole 2 g single oral dose (alternative option) 2
Diagnostic Approach to Guide Treatment
Bacterial Vaginosis
- Diagnosis using Amsel criteria: milky discharge, pH > 4.5, positive whiff test, clue cells 4
- Gram stain is the diagnostic standard 4
Vulvovaginal Candidiasis
- Thick, white discharge, dysuria, vulvovaginal pruritus and swelling 7
- Confirmed with microscopic examination (10-20% potassium hydroxide preparation) 7
Trichomoniasis
- Foul-smelling, frothy discharge, vaginal inflammatory changes 7
- Best detected by nucleic acid amplification testing or antigen testing 6
Special Considerations
Pregnancy
- For bacterial vaginosis: Metronidazole 250 mg orally (dosage adjustment) 1
- Avoid oral fluconazole for candidiasis; use only topical azoles 4
- Treatment of symptomatic trichomoniasis with oral metronidazole is warranted for prevention of preterm birth 6
Recurrent Infections
- For recurrent vulvovaginal candidiasis: Maintenance of weekly oral fluconazole for up to 6 months 6
- For recurrent bacterial vaginosis: Longer courses of therapy are recommended 6
Partner Treatment
- Not recommended for bacterial vaginosis 1
- Recommended for trichomoniasis even without screening (enhances cure rates) 6
Follow-Up Recommendations
- For bacterial vaginosis: Follow-up visits unnecessary if symptoms resolve 1
- For trichomoniasis: Test of cure not recommended 6
- For vulvovaginal candidiasis: Follow-up based on symptom resolution
Important Cautions
- Patients should avoid alcohol during treatment with metronidazole and for 24 hours afterward 1
- Clindamycin cream and ovules are oil-based and might weaken latex condoms and diaphragms 1
- In case of metronidazole allergy, clindamycin is the preferred alternative 1
When empirically treating vaginitis without a definitive diagnosis, consider that bacterial vaginosis is the most common cause, followed by vulvovaginal candidiasis and trichomoniasis. Starting with metronidazole 500 mg orally twice daily for 7 days provides coverage for both bacterial vaginosis and trichomoniasis, the two most common infectious causes.