Gonococcal urethritis is an infection of the urethra caused by the bacterium Neisseria gonorrhoeae, the same organism responsible for gonorrhea. It’s one of the most common sexually transmitted infections worldwide, and its hallmark is a noticeable, often thick discharge from the penis along with pain during urination. The infection is highly treatable with a single antibiotic injection, but left alone it can lead to serious complications.
How the Infection Takes Hold
During unprotected sexual contact, the gonorrhea bacterium lands on the lining of the urethra and begins a step-by-step invasion. First, tiny hair-like structures on the bacterium’s surface latch onto urethral cells. Once loosely attached, the bacterium locks in more tightly by binding to a specific receptor on those cells. This triggers the urethral cells to form small pedestals beneath the bacterium, essentially pulling it inward. The cell’s internal scaffolding reorganizes to engulf the bacterium in a process sometimes described as a “zipper mechanism,” where the cell membrane wraps snugly around the invader rather than swallowing it in a large gulp.
This process is efficient. A single unprotected encounter with an infected partner carries a transmission risk estimated between roughly 20% and 50%, and the risk climbs with repeated exposures. Even men who aren’t infected after a first encounter are likely susceptible if exposure continues.
Symptoms and How Quickly They Appear
Gonococcal urethritis typically produces symptoms within two to five days of exposure, though some people notice them as late as two weeks. The classic presentation includes a thick, yellowish or white discharge from the urethra, pain or burning during urination, and itching inside the urethra. The discharge tends to be heavier and more obviously pus-like than what’s seen with other forms of urethritis, which is a useful clinical clue.
Not everyone develops symptoms, though. A meaningful percentage of infected men, and an even larger proportion of infected women, can carry the bacterium without any noticeable signs. Asymptomatic carriers still transmit the infection to sexual partners, which is one reason gonorrhea spreads so effectively.
How It Differs From Non-Gonococcal Urethritis
Urethritis has two broad categories: gonococcal (caused by gonorrhea) and non-gonococcal (caused by other organisms, most commonly chlamydia). The distinction matters because treatment differs. Gonococcal urethritis tends to produce a more profuse, purulent discharge and symptoms that appear faster. Non-gonococcal urethritis, by contrast, often causes a thinner, clearer discharge and milder discomfort that develops more gradually over one to three weeks.
Co-infection is common. Many people with gonococcal urethritis also carry chlamydia at the same time, which is why testing for both infections is standard practice whenever either one is suspected.
Testing and Diagnosis
The most reliable way to confirm gonococcal urethritis is a nucleic acid amplification test, or NAAT. This test detects the bacterium’s genetic material from either a urine sample or a urethral swab. NAATs are highly accurate, with sensitivity above 95% and specificity above 99% for urine samples and swabs in men. That means false negatives and false positives are both uncommon.
In clinical settings where results are needed quickly, a Gram stain of the urethral discharge can provide a presumptive diagnosis within minutes. If the stain shows white blood cells containing characteristic paired, kidney-bean-shaped bacteria, gonococcal infection is highly likely. However, NAAT confirmation is still recommended because Gram stain alone can miss some cases.
Treatment
The current standard treatment is a single intramuscular injection of ceftriaxone at 500 mg (or 1 gram for people weighing over 300 pounds). This one-time shot cures the vast majority of uncomplicated gonococcal infections in the urethra. There’s no course of pills to remember, no week-long regimen. You get the injection at a clinic and the infection clears.
Because co-infection with chlamydia is so frequent, your provider will likely test for it simultaneously. If chlamydia is also present, or if it can’t be ruled out, an oral antibiotic is added to cover that second infection.
Sexual partners from the past 60 days should be notified and treated as well, even if they have no symptoms. You’ll also want to avoid sexual contact for at least seven days after treatment and until any partners have been treated, to prevent passing the infection back and forth.
Why Antibiotic Resistance Matters
Gonorrhea has steadily developed resistance to nearly every antibiotic class used against it over the decades. Older treatments like ciprofloxacin are now useless in many regions, with resistance rates reaching 100% in some countries. WHO surveillance data from 2017 to 2018 found that up to 21% of gonorrhea samples in certain countries showed decreased susceptibility to ceftriaxone, the current frontline treatment, and up to 60% showed resistance to azithromycin, which was previously used alongside it.
This is the reason the treatment guidelines have narrowed to a single recommended drug rather than offering alternatives. It also means follow-up testing after treatment (typically one to two weeks later) is important. If symptoms don’t resolve, resistance may be the cause, and your provider will need to try a different approach.
Complications of Untreated Infection
When gonococcal urethritis goes untreated or is inadequately treated, the infection can spread beyond the urethra. In men, the most common local complication is epididymo-orchitis, a painful infection of the structures near the testicles that can affect fertility if it becomes severe or recurrent. Prostatitis, an infection of the prostate gland, is another possibility.
In rare cases, the bacteria enter the bloodstream and cause disseminated gonococcal infection. This can produce joint pain and swelling, skin lesions, and in the most serious scenarios, infection of the heart valves (endocarditis) or the membranes surrounding the brain (meningitis). These severe complications are uncommon but underscore why prompt treatment matters.
For women, untreated gonorrhea can ascend from the cervix into the uterus and fallopian tubes, causing pelvic inflammatory disease. This can lead to chronic pelvic pain, scarring, and infertility. Pregnant individuals with untreated gonorrhea can also pass the infection to their newborn during delivery, potentially causing serious eye infections in the baby.