What is the recommended dosing for Flagyl (metronidazole) in the treatment of trichomoniasis?

From the Guidelines

For trichomoniasis treatment, the recommended dosage of Flagyl (metronidazole) is 2 grams (2,000 mg) taken as a single oral dose, as this regimen has been shown to be highly effective with cure rates of approximately 90-95% 1.

Key Considerations

• This one-time treatment is preferred due to its high efficacy and convenience.
• Alternatively, metronidazole can be prescribed as 500 mg twice daily for 7 days, which may be preferred for patients who cannot tolerate the single large dose 1.
• Patients should avoid alcohol consumption during treatment and for at least 48 hours after the last dose to prevent a disulfiram-like reaction (nausea, vomiting, flushing, headache) 1.

Treatment and Prevention

• Sexual partners should also be treated simultaneously to prevent reinfection, even if they are asymptomatic 1.
• Metronidazole works by entering the trichomonal cells and disrupting their DNA, ultimately killing the parasites.
• Patients should abstain from sexual intercourse until both they and their partner(s) have completed treatment and symptoms have resolved.
• If symptoms persist after treatment, follow-up evaluation is recommended to rule out reinfection or treatment failure.

From the FDA Drug Label

Trichomoniasis In the Female One-day treatment— two grams of metronidazole tablets, given either as a single dose or in two divided doses of one gram each given in the same day Seven-day course of treatment— 250 mg three times daily for seven consecutive days.

The recommended dosing for Flagyl (metronidazole) in the treatment of trichomoniasis is:

• One-day treatment: 2 grams of metronidazole tablets, given either as a single dose or in two divided doses of 1 gram each, given in the same day.
• Seven-day course of treatment: 250 mg three times daily for seven consecutive days 2.

From the Research

Flagyl Dosing for Trichomoniasis

• The recommended dosing for Flagyl (metronidazole) in the treatment of trichomoniasis is a single dose of 2 g or 500 mg twice daily for 7 days 3, 4, 5, 6.
• A study published in The Lancet found that the 7-day dose of metronidazole was more effective than the single dose in treating trichomoniasis among women, with a lower rate of treatment failure 3.
• Another study published in the Journal of Acquired Immune Deficiency Syndromes found that the 7-day dose of metronidazole was more effective than the single dose in treating trichomoniasis among HIV-infected women 6.
• The Centers for Disease Control and Prevention (CDC) recommend a single dose of 2 g of metronidazole as the first-line treatment for trichomoniasis, but also suggest that a 7-day course of treatment may be necessary in some cases 4.
• Metronidazole is generally well-tolerated, but common side effects include nausea, headache, and vomiting 3, 5, 7.

Treatment Efficacy

• The efficacy of metronidazole in treating trichomoniasis is high, with cure rates ranging from 93.8% to 97.3% 5.
• However, some studies have found that the single dose of metronidazole may not always clear the infection, and that the 7-day dose may be more effective in certain cases 3, 6.
• The presence of bacterial vaginosis may also affect the efficacy of metronidazole treatment, although the evidence is not consistent 3, 4.

Special Considerations

• HIV-infected women may require a 7-day course of metronidazole to effectively treat trichomoniasis 6.
• Pregnant women should only use metronidazole under the guidance of a healthcare provider, as the safety of the drug during pregnancy is not well-established 7.
• Metronidazole should not be used prophylactically, and should only be used for approved indications except in the research setting 7.