Mycoplasma genitalium treatment: why azithromycin fails more often

Treating mycoplasma genitalium has clearly become harder in recent years. A global meta-analysis showed that resistance to macrolides, the class azithromycin belongs to, rose sharply over time (Machalek, 2020). An updated review from 2025 did not see that pattern reverse (Chua, 2025).

That is the core of this article.

The drug that was long the first choice no longer works for a growing share of infections. We do not prescribe antibiotics and will not start here. What we can do is explain why your GP handles this differently from chlamydia.

How is mycoplasma genitalium treated?

With antibiotics, but not from a fixed prescription. The 2021 European guideline describes an approach where resistance mutations are identified first, and the choice of drug follows from that (Jensen, 2022). It is called resistance-guided treatment and it differs fundamentally from the chlamydia approach.

With chlamydia the route is largely fixed.

With mycoplasma genitalium it is not. Which antibiotic fits depends on what the lab finds. So this is not a situation where you order something yourself or finish an old course. Which drugs exist in the Netherlands and what they are registered for is described in the Farmacotherapeutisch Kompas. What fits your case is for your doctor to decide.

Why does azithromycin increasingly fail?

Because the bacterium developed mutations that render macrolides ineffective. Those mutations are found more often the more widely the drug has been used. The Machalek meta-analysis describes exactly that link: the more macrolides are used, the higher the share of resistant infections (Machalek, 2020).

There is a painful logic in it.

Every unnecessary course pushes resistance along a little further. That is also the argument for advising against untargeted testing for this bacterium: every symptom-free positive that gets treated anyway adds to the problem. More on that in mycoplasma genitalium as an STI.

This table summarises what the literature reports. It is not a treatment schedule. Dosing and sequence belong with your doctor, not a blog.

What if the first course does not work?

Then a second round is more complicated than the first. If symptoms persist or the bacterium returns on a follow-up test, the guideline looks to a different drug based on the resistance profile (Jensen, 2022). Repeating the old course yourself is the least promising route here.

What you can do is prepare the conversation well.

Picture two men aged 32 given the same first course. For one, symptoms are gone after 7 days. For the other they are not, and only then does the lab show a resistant variant.

You cannot see that difference in the symptoms beforehand, and it is exactly why we've come to prefer waiting for resistance testing over guessing.

Bring when symptoms started, which course you had, and whether you finished it. Bring whether your partner was treated too, because otherwise the infection can keep travelling back and forth. How to have that conversation is covered in notifying your partner.

Can mycoplasma genitalium be cured?

In many cases yes, but it can take more than one round of treatment. The guideline describes a follow-up test after treatment to confirm the bacterium has gone (Jensen, 2022). That differs from infections where a check is usually unnecessary, and it follows directly from the resistance problem.

What "symptom-free" means here matters.

Symptoms that linger a while after successful treatment do not automatically mean the bacterium is still there. The lining of the urethra needs time. Conversely, the bacterium can be gone while something else, such as irritation, still bothers you. That distinction is worked out in urethritis.

What can you do yourself?

The honest answer is: not much, beyond ruling out the common causes and then seeing a doctor. No self-care product clears this bacterium. What does help is avoiding sex until treatment is finished, so you do not pass the infection on or get it back.

You can take the first step with us through a test for chlamydia, gonorrhoea and trichomonas. If that finds nothing and symptoms persist, that is the signal to look further.

Thuisarts.nl, the patient platform of the Dutch College of General Practitioners, explains how to raise a complaint like this with your GP. The Dutch GP standard on the STI consultation describes how this is handled in the Netherlands.

Further reading

For the overview of all causes of urethral symptoms: urethritis. For whether mycoplasma is an STI and why a standard panel misses it: mycoplasma genitalium as an STI.

Resistance plays a role in gonorrhoea too. That story is in gonorrhoea treatment and resistance.

References

• Machalek DA, et al. Prevalence of mutations associated with resistance to macrolides and fluoroquinolones in Mycoplasma genitalium: a systematic review and meta-analysis. The Lancet Infectious Diseases, 2020. PMID 32622378.
• Chua TP, et al. Evolving patterns of macrolide and fluoroquinolone resistance in Mycoplasma genitalium: an updated systematic review and meta-analysis. The Lancet Microbe, 2025. PMID 40147462.
• Jensen JS, et al. 2021 European guideline on the management of Mycoplasma genitalium infections. Journal of the European Academy of Dermatology and Venereology, 2022. PMID 35182080.
• Farmacotherapeutisch Kompas, Zorginstituut Nederland. Accessed July 2026.
• NHG-Standaard Het soa-consult, Dutch College of General Practitioners. Accessed July 2026.
• Thuisarts.nl, Pain when urinating. Accessed July 2026.

Every test result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.