Important Mgen (Mycoplasma genitalium) Update

Thanks to our ongoing testing efforts, rates of Mycoplasma genitalium (Mgen) continue to decline. However, there are a few important treatment reminders for anyone diagnosed with Mgen.

If you test positive, it is essential to take all prescribed antibiotics exactly as directed and complete the entire course of treatment, even if your symptoms improve or you receive a negative test result before treatment is finished.

We have recently become aware that some individuals are taking only the first week of treatment, obtaining a negative test result after seven days, and then stopping therapy without completing the second antibiotic. This can lead to treatment failure, antibiotic resistance, ongoing transmission, and the need for additional treatment and time away from work.

The preferred treatment regimen for Mgen is:

• Doxycycline 100 mg twice daily for 7 days, immediately followed by

• Moxifloxacin 400 mg once daily for 7 days

Doxycycline alone clears only about 30–40% of Mgen infections. The purpose of the two-step treatment approach is to first reduce the bacterial burden with doxycycline, allowing moxifloxacin to more effectively eliminate the infection. While doxycycline may temporarily lower the bacterial count enough to produce a negative test result, it often does not fully eradicate the infection when used alone.

Regimens containing azithromycin are generally not recommeded due to higher rates of antibiotic resistance compared with the doxycycline-plus-moxifloxacin regimen.

For individuals who do not respond to first-line treatment, additional treatment options are available. These cases should be managed by a healthcare provider experienced in the diagnosis and treatment of sexually transmitted infections.