Treatment of Mycoplasma hominis Vaginal Infections

The recommended treatment for Mycoplasma hominis vaginal infections is doxycycline 100 mg orally twice daily for 7 days. 1

First-Line Treatment Options

Doxycycline 100 mg orally twice daily for 7 days is the preferred first-line treatment for M. hominis vaginal infections 1
This regimen has been shown to be effective against M. hominis and is recommended in CDC treatment guidelines for non-gonococcal urethritis, which can be caused by M. hominis 1

Erythromycin base 500 mg orally four times a day for 7 days 1
Erythromycin ethylsuccinate 800 mg orally four times a day for 7 days 1
For patients who cannot tolerate high-dose erythromycin, lower doses may be used but for a longer duration:
- Erythromycin base 250 mg orally four times a day for 14 days 1
- Erythromycin ethylsuccinate 400 mg orally four times a day for 14 days 1

If symptoms persist after initial treatment, consider the following approach:

Rule out reinfection from untreated partners 1
Verify patient compliance with the initial treatment regimen 1
If reinfection and non-compliance are excluded, consider:
- Metronidazole 2 g orally in a single dose PLUS
- Erythromycin base 500 mg orally four times a day for 7 days 1

M. hominis is often found in high concentrations in bacterial vaginosis (BV) 1. If BV is present with M. hominis, treatment options include:

Metronidazole 500 mg orally twice daily for 7 days 1, 2
Metronidazole gel 0.75%, one full applicator (5 g) intravaginally once daily for 5 days 1, 2
Clindamycin cream 2%, one full applicator (5 g) intravaginally at bedtime for 7 days 1, 2

During first trimester: Clindamycin vaginal cream is preferred due to contraindication of metronidazole 1, 2
During second and third trimesters: Oral metronidazole can be used 1, 2

Patients with HIV and M. hominis infections should receive the same treatment regimen as those who are HIV-negative 1

Clindamycin cream or oral clindamycin is preferred in case of allergy or intolerance to tetracyclines 1, 2
Patients allergic to oral metronidazole should not be administered metronidazole vaginally 1, 2

Sex partners of patients with M. hominis infections should be evaluated and treated if their last sexual contact with the index patient was within 30 days of symptom onset 1
If the index patient is asymptomatic, sex partners whose last sexual contact was within 60 days of diagnosis should be evaluated and treated 1
Patients and their sex partners should abstain from sexual intercourse until therapy is completed (i.e., 7 days after completion of treatment) 1

Follow-up visits are unnecessary if symptoms resolve 1, 2
Patients should be instructed to return for evaluation if symptoms persist or recur after completion of therapy 1
Persistent or recurrent symptoms may indicate reinfection, non-compliance with treatment, or resistance to the prescribed antibiotic 1

M. hominis lacks a cell wall, making it naturally resistant to beta-lactam antibiotics (penicillins, cephalosporins) 3
Culture of M. hominis is not routinely recommended as a diagnostic tool because it is not widely available and requires special media 1
Septic arthritis caused by M. hominis is a rare complication that occurs primarily in immunosuppressed hosts or in the postpartum period 3
When treating M. hominis in the context of BV, remember that oil-based clindamycin creams and ovules may weaken latex condoms and diaphragms 1, 2
Patients using metronidazole should avoid alcohol during treatment and for 24 hours afterward due to potential disulfiram-like reaction 1, 2