Most men with trichomoniasis have no symptoms at all, which makes this infection notoriously difficult to spot without a lab test. Studies show that 60% to 77% of men infected with the parasite carry it without any noticeable signs. When symptoms do appear, they tend to be mild and easy to dismiss or mistake for something else.
Symptoms That Can Appear
The men who do develop symptoms typically notice one or more of the following:
- Irritation or itching inside the penis, often described as a persistent tickling or burning sensation at the tip of the urethra
- Burning after urination or ejaculation, which can range from faint discomfort to a sharp sting
- A thin discharge from the penis, usually clear or slightly whitish, and often so slight it only appears as a small spot on underwear
These symptoms can show up anywhere from 5 to 28 days after exposure, though many men never develop them at all. When discharge is present, it’s typically much lighter than what you’d see with gonorrhea, which tends to produce a thicker, more obvious discharge. This subtlety is part of why trichomoniasis in men goes unnoticed so often.
The overlap with other infections is another challenge. Burning during urination and mild discharge are also hallmarks of chlamydia and other urethral infections. There’s no way to tell these apart based on symptoms alone, which is why testing matters so much.
Why Most Men Don’t Know They Have It
One U.S. study tracked 177 men whose female sexual partners had confirmed trichomoniasis. Of those men, 137 were also infected, but 77% had zero symptoms. A separate study found that even among men who tested positive through urine cultures, 61% had no clinical abnormalities at all. These aren’t edge cases. Asymptomatic infection is the norm for men with trichomoniasis.
This creates a real public health problem. A man can carry and transmit the parasite for weeks or months without any reason to suspect he’s infected. The infection can clear on its own in some cases, but it can also persist silently, particularly if the parasite reaches the prostate.
What Happens If It Goes Untreated
Left alone, trichomoniasis in men can lead to more than just urethral irritation. The parasite can travel up the urethra and affect the prostate, causing inflammation (prostatitis) that brings its own set of problems: pelvic pain, frequent urination, and difficulty urinating. It can also inflame the epididymis, the coiled tube behind each testicle where sperm matures.
Persistent infection has been linked to impaired sperm function and reduced fertility. There’s also a well-established connection between trichomoniasis and HIV transmission. Active infection increases the amount of HIV shed in seminal fluid, which raises the risk of passing HIV to a partner. For older men, particularly those already dealing with an enlarged prostate, trichomoniasis can worsen urinary symptoms significantly by adding infection-driven inflammation on top of existing issues.
How Testing Works for Men
Because symptoms are unreliable, a lab test is the only way to confirm trichomoniasis in men. The two main approaches are older culture-based tests and newer molecular tests, and the difference in accuracy is dramatic.
Traditional culture methods catch only 44% to 75% of infections in men. That means a negative culture result doesn’t rule the infection out. Newer molecular tests (called nucleic acid amplification tests) are far more reliable, detecting 96% to 100% of infections with near-perfect accuracy. These tests work on a simple urine sample, making them easy and noninvasive. A urethral swab is another option, though urine-based testing is increasingly standard.
If you’re providing a urine sample, your provider will likely ask you to use the first part of your urine stream rather than a midstream catch, since the goal is to collect cells and organisms from the urethra itself. At-home STI kits that test for trichomoniasis are also available and use the same urine sample approach, with the sample mailed to a lab for processing.
When to Get Tested
Trichomoniasis isn’t part of standard STI screening panels for men in most clinics. Testing is typically done when a female partner has been diagnosed, when a man has symptoms of urethral irritation, or when other STI tests come back negative but symptoms persist. If your partner has been diagnosed with trichomoniasis, you should be tested and treated regardless of whether you have symptoms, since the odds of being infected are high.
One important note: the CDC recommends retesting about three months after treatment to catch repeat infections. Reinfection is common if both partners aren’t treated simultaneously, and a man can easily pick up the parasite again from an untreated partner. Treatment itself is straightforward, involving a single course of oral antibiotic, and both partners need to be treated at the same time and avoid sexual contact until the medication has fully worked.
The Practical Takeaway
You generally cannot tell if a man has trichomoniasis just by looking for symptoms. The majority of infected men feel perfectly fine. The most reliable indicator isn’t a symptom at all. It’s a partner’s diagnosis. If a female partner tests positive, the man should assume he’s likely infected and get tested with a molecular urine test, which catches infections that older methods miss. Mild burning or discharge after sex with a new partner is worth testing for as well, since trichomoniasis is one of several infections that can cause those symptoms and is easily treated once identified.