What is the treatment for Trichomoniasis?

Treatment of Trichomoniasis

Metronidazole 500 mg orally twice daily for 7 days is the preferred first-line treatment for trichomoniasis, demonstrating superior cure rates (90-95%) compared to single-dose therapy. 1

Primary Treatment Regimens

The CDC-recommended approach prioritizes the 7-day regimen over single-dose therapy based on recent comparative evidence:

• Metronidazole 500 mg orally twice daily for 7 days achieves cure rates of 90-95% and is now the preferred regimen 1, 2
• Metronidazole 2 g orally as a single dose remains an acceptable alternative with cure rates of approximately 81-90%, though slightly inferior to the 7-day regimen 3, 2, 4
• A 2018 randomized controlled trial demonstrated significantly better efficacy with the 7-day regimen (89% cure rate) versus single-dose (81% cure rate), with relative risk of treatment failure 0.55 (p<0.0001) 4

Tinidazole 2 g orally as a single dose is an FDA-approved alternative for patients who cannot tolerate metronidazole 5

Critical Management Principles

Partner Treatment (Non-Negotiable)

• All sexual partners must be treated simultaneously - this is mandatory, not optional 1, 3, 2, 6
• Failure to treat partners is the single most common cause of recurrent infection 1
• Patients must abstain from sexual activity until both partners complete treatment and are asymptomatic 1, 3, 2

Alcohol Avoidance

• Patients must avoid alcohol during treatment and for at least 24-48 hours after completing metronidazole therapy to prevent disulfiram-like reactions (nausea, vomiting, flushing, headache, abdominal cramps) 3, 2

Treatment Failure Algorithm

When initial therapy fails, follow this stepwise escalation:

1. First treatment failure: Re-treat with metronidazole 500 mg twice daily for 7 days 1, 3, 2
2. Second treatment failure: Metronidazole 2 g once daily for 3-5 days 1, 3, 2
3. Persistent failure: Consult infectious disease specialist and consider susceptibility testing if reinfection has been excluded 3, 2

Special Populations

Pregnancy

• Metronidazole is contraindicated in the first trimester 7
• After the first trimester: Metronidazole 2 g orally as a single dose can be safely administered 7, 1

Breastfeeding

• The 7-day regimen may be preferred if the patient cannot interrupt breastfeeding, as the lower daily dose results in less drug accumulation in breast milk 2

HIV-Infected Patients

• Use the same treatment regimens as HIV-negative patients - no modification needed 7, 1, 3, 2

Metronidazole Allergy

• Desensitization may be required, as nitroimidazoles (metronidazole and tinidazole) are the only effective oral drug class for trichomoniasis 3, 2

Follow-Up Recommendations

• Routine follow-up is unnecessary for patients who become asymptomatic after treatment 7, 1, 3
• Re-evaluate only if symptoms persist, considering reinfection (most common) or resistant infection 1, 3

Critical Pitfalls to Avoid

Never Use Topical Metronidazole

• Topical metronidazole gel has efficacy <50% for trichomoniasis and should NEVER be used 1, 3, 2
• Topical preparations fail to achieve therapeutic levels in the urethra and perivaginal glands 1
• The FDA has approved metronidazole gel only for bacterial vaginosis, not trichomoniasis 7, 6
• Even high-dose intravaginal metronidazole/miconazole combinations show only 78-80% cure rates, inferior to oral therapy 8

Common Causes of Treatment Failure

• Untreated sexual partners (most common cause) 1, 2
• Using topical instead of oral therapy 1, 2
• Patient non-adherence to the 7-day regimen 4
• True metronidazole resistance (rare) 9