Chlamydial urethritis is inflammation of the urethra caused by the bacterium Chlamydia trachomatis. In men it often causes penile discharge and burning on urination, but it's frequently silent. Left untreated, it can spread to the testicles and cause painful, fertility-threatening complications. A short course of antibiotics clears it.
| Item | Reported cases |
|---|---|
| Chlamydia | 1,648,568 |
| Gonorrhea | 601,319 |
| Syphilis (P&S) | 53,007 |
The essentials: what chlamydial urethritis is
Chlamydial urethritis is caused by Chlamydia trachomatis, and most genital infections in the US come from serovars D through K CDC, About Chlamydia. The bacterium infects the lining of the urethra, the tube that carries urine and semen out through the penis, where it triggers inflammation, discharge, and the stinging sensation people notice when they pee. It's the most commonly reported bacterial STI in the country, with about 1.65 million reported cases in 2023, a rate of roughly 492 per 100,000 that has stayed about flat across recent years CDC AtlasPlus, 2023.
It can be remarkably quiet. Roughly half of infected men and about three quarters of infected women have no symptoms at all, which is why so much of it spreads unknowingly. The burden is uneven geographically too, with Washington DC, Louisiana, and Mississippi reporting rates more than double the national average. If you're worried, treatment cures chlamydia.
Chlamydia and gonorrhea cause overlapping symptoms and often travel together, so clinicians frequently test and sometimes treat for both at once. If you're trying to sort out which one you might have, see our comparison of chlamydia vs gonorrhea.
Symptoms in men — and the complications that hurt
When chlamydial urethritis does cause symptoms in men, they usually show up at the front end of the urinary tract:
- Penile discharge, often clear or cloudy, sometimes only a single drop noticed in the morning before urinating.
- Burning on urination, the classic stinging sensation as urine passes through the inflamed urethra.
- Burning or itching right at the penile opening (the urethral meatus).
- Testicular pain or swelling, which signals the infection may have spread beyond the urethra.
That last symptom is the warning sign. The painful complication men should know about is epididymitis, inflammation of the epididymis, the coiled tube behind the testicle that stores and carries sperm. It typically presents as one-sided testicular pain, swelling, and tenderness, and in untreated cases it can scar the tube and affect fertility. The old idea that chlamydia is "just a women's problem" is wrong: the spread happens silently, then announces itself with real pain.
Men can also carry chlamydia at sites beyond the penis. Rectal infection may cause rectal pain, discharge, or bleeding, but it's often completely silent. Throat (pharyngeal) infections are typically asymptomatic. Because so much infection produces no symptoms, you cannot rule it out by how you feel. Only testing does that.
Lymphogranuloma venereum (LGV): a more invasive form
A small but important subset of chlamydia comes from the invasive serovars L1, L2, and L3, which cause lymphogranuloma venereum. The burden is highest among men who have sex with men, and the usual presentation is proctocolitis, inflammation of the rectum and colon with mucoid or bloody rectal discharge, anal pain, and tenesmus (the painful, persistent urge to pass stool even when the rectum is empty) CDC, LGV. LGV needs a longer antibiotic course than ordinary chlamydia, so clinicians need to recognize it.
Testing: how it's diagnosed and when
The recommended and most accurate test is a NAAT (nucleic acid amplification test), which detects the bacterium's genetic material and works for both genital and extragenital sites CDC STI Guidelines, 2021. Specimens can be a first-catch urine sample, a male urethral swab, or, for other exposure sites, rectal and pharyngeal swabs.
For men, it's simpler than most expect. You usually pee into a cup (first-catch urine, after holding it for about an hour), or self-collect a swab. No blood draw and, in most cases, no uncomfortable urethral swab. Results are often texted back within a few days.
Timing trips most people up. A NAAT is most reliable about two weeks after exposure, so getting tested the morning after a hookup can produce a falsely reassuring negative. Read up on the right interval at when to test after exposure before you book. For the full step-by-step on samples and accuracy, see chlamydia testing & diagnosis, and when you're ready you can get tested.
On access and cost: testing is free or low-cost at Planned Parenthood, local health departments, and Title X clinics; at-home kits typically run about $50–150; and it's often $0 with insurance. The USPSTF gives a Grade B recommendation to screen sexually active women 24 and under, but issues an I-statement (insufficient evidence) for screening men, because the heaviest complication burden, including pelvic inflammatory disease and infertility, falls on women USPSTF. That doesn't mean men shouldn't test. It means men should test based on symptoms and exposure rather than wait for a blanket screening rule.
Treatment: what cures it
The preferred regimen is doxycycline 100 mg by mouth twice daily for 7 days CDC Treatment Guidelines. Alternatives include azithromycin 1 g as a single oral dose, or levofloxacin 500 mg once daily for 7 days. In practice, doxycycline means taking a pill twice a day for a week. Take it with food and avoid strong sun exposure, since the drug can make skin sun-sensitive.
Azithromycin used to be co-equal with doxycycline but was downgraded, because microbiologic treatment failure in men ran higher than with doxycycline, and doxycycline clears rectal infection far better. In one randomized trial, doxycycline cured rectal chlamydia in 100% of cases versus 74% with single-dose azithromycin, the main reason the 2021 guidelines made doxycycline first-line Rectal CT RCT.
| Regimen | Dose | Best for |
|---|---|---|
| Doxycycline (preferred) | 100 mg twice daily for 7 days | Most infections; clearly better for rectal infection |
| Azithromycin (alternative) | 1 g single dose | Adherence concerns; preferred in pregnancy |
| Levofloxacin (alternative) | 500 mg once daily for 7 days | When doxycycline/azithromycin aren't options |
| Pregnancy | Azithromycin 1 g single dose (alt: amoxicillin 500 mg three times daily for 7 days) | Pregnant patients |
| LGV | Doxycycline 100 mg twice daily for 21 days | Invasive L-serovar infection |
Treating partners is part of the cure. Partners from the prior 60 days should be referred, tested, or presumptively treated, and you should abstain from sex for 7 days after single-dose therapy or until the full 7-day course is done, otherwise you risk "ping-pong" reinfection. Expedited partner therapy (EPT), where you carry medication to a partner, works measurably: in a landmark trial it cut persistent or repeat infection, with the biggest benefit for gonorrhea (3% vs 11%) Golden et al., NEJM. EPT is permissible in most but not all US states, so check local status. In many states you can also notify partners anonymously through a clinic.
Retesting and test-of-cure
Plan to retest about 3 months after treatment. This is not a test-of-cure. It catches reinfection, which is common because a treated person often returns to the same untreated partner network. A test-of-cure is not advised for non-pregnant people unless adherence is in doubt, symptoms persist, or reinfection is suspected. Pregnant patients are the exception: they get a test-of-cure about 4 weeks after finishing treatment and a retest at 3 months. Put that 3-month check in your calendar now, and see more on chlamydia reinfection.
Prevention that actually works
Condoms used correctly every time lower your risk, and a long-term mutually monogamous relationship with a tested partner is protective. But because most infections are silent, the interventions that move the needle most are routine screening and getting partners treated. You can't avoid what nobody knows is there.
There's also DoxyPEP: a single 200 mg dose of doxycycline taken within 72 hours after sex, which reduces chlamydia by more than 70% CDC DoxyPEP, 2024. Under current CDC guidance it's offered to men who have sex with men and transgender women who've had a bacterial STI in the past year. It's a targeted tool, not a substitute for condoms or screening.
When to see a clinician
Get checked if you have penile discharge, burning on urination, or itching at the tip of the penis. Seek care promptly for testicular pain or swelling, which can mean the infection has reached the epididymis. Test too if a partner tells you they've been diagnosed, even if you feel fine. Testing positive is routine and curable. Clinics handle it every day, and it's a medical event, not a character verdict.