Many STIs in men produce no symptoms at all, which means you can’t rely on how you feel to know your status. Half of men with chlamydia and up to 40% of men with gonorrhea never develop noticeable signs. The only reliable way to know is testing. That said, there are specific symptoms worth watching for, and understanding what different infections look and feel like can help you act faster.
Symptoms You Might Notice
The most common early signs of an STI in men involve the urinary tract and genitals. Burning or pain during urination, unusual discharge from the penis (clear, white, yellow, or green), and itching or irritation at the tip of the penis are the hallmarks of infections like chlamydia, gonorrhea, and trichomoniasis. Trichomoniasis can also cause burning after ejaculation. These symptoms can appear within a few days to a few weeks after exposure, but again, many men with these infections feel completely fine.
Pain or swelling in one testicle is a more concerning sign. Untreated chlamydia or gonorrhea can spread to the epididymis, the coiled tube behind each testicle. This causes tenderness, swelling, and sometimes a visible fluid buildup around the testicle. Left untreated, it can lead to chronic pain or fertility problems.
What Different Infections Look Like
Some STIs cause visible changes on the skin, and knowing what to look for helps you tell them apart.
Genital warts (HPV) appear as small, skin-colored bumps that can be raised or flat. They sometimes have a rough, cauliflower-like texture. They’re usually painless.
Herpes looks different. It starts with a tingling or burning sensation in one area, followed by a cluster of small blisters or open sores that are often painful. The sores eventually crust over and heal, but the virus stays in the body and can cause future outbreaks.
Syphilis is easy to miss in its earliest stage. The first sign is a small, hard, painless sore called a chancre that appears two to 12 weeks after exposure. It can show up on the penis, scrotum, under the foreskin, around the anus, or on the lips or mouth. It may look like a pimple and can be so small you don’t notice it. It goes away on its own in about six weeks, which tricks many people into thinking nothing is wrong. But one to six months later, a rough, red or brown rash can spread across the body, including the palms and soles of the feet. The rash typically doesn’t itch. Syphilis is very treatable but causes serious damage if ignored.
HIV: The Flu That Isn’t the Flu
About two-thirds of people who contract HIV develop flu-like symptoms within two to four weeks. These include fever, chills, night sweats, muscle aches, sore throat, fatigue, swollen lymph nodes, mouth ulcers, and sometimes a rash. The symptoms last a few days to several weeks and then disappear. After that, HIV can remain silent for years while progressively damaging the immune system. Because the early symptoms look exactly like a regular flu, the only way to identify HIV at this stage is a test.
Why Symptoms Alone Aren’t Enough
The core problem is math. When half of chlamydia cases and 40% of gonorrhea cases in men cause zero symptoms, and roughly 70% of trichomoniasis infections are silent, waiting for something to feel wrong means you could be carrying and transmitting an infection for months or years. Syphilis hides behind a painless sore that disappears. HIV mimics the flu. You simply cannot rule out an STI based on feeling healthy.
How STI Testing Works for Men
Testing is straightforward and less invasive than most men expect. For chlamydia, gonorrhea, and trichomoniasis, you’ll typically provide a urine sample in a cup. That’s it for the most common bacterial infections. If you’ve had oral or anal sex, your provider may use a swab at the throat or rectum to check those sites directly. Herpes is diagnosed by swabbing an active sore, while HPV is identified by a visual exam or swab of a wart. HIV, syphilis, and hepatitis B and C are all detected through blood tests, and some clinics offer a rapid oral swab for HIV that gives results in minutes.
When to Get Tested After Exposure
Testing too soon after a possible exposure can produce a false negative because the infection hasn’t built up enough to detect. Each STI has its own window:
- Chlamydia and gonorrhea: A urine test or swab is reliable after one week and catches nearly all infections by two weeks.
- Syphilis: A blood test catches most infections at one month and nearly all by three months.
- HIV (blood test): An antigen/antibody blood test detects most infections at two weeks and nearly all by six weeks. An oral swab takes longer, catching most at one month and nearly all by three months.
If you’re concerned about a specific exposure, testing at the two-week mark covers chlamydia and gonorrhea well, but you may need a follow-up at six weeks or three months to get reliable HIV and syphilis results.
How Often You Should Be Tested
The CDC recommends every adult between 13 and 64 get tested for HIV at least once. Beyond that baseline, your testing schedule depends on your sexual activity.
Men who have sex with men should test for syphilis, chlamydia, and gonorrhea at least once a year, and for HIV at least annually. If you have multiple partners or anonymous partners, every three to six months is more appropriate. Men on PrEP or living with HIV typically follow that more frequent schedule as well. Testing should cover every site of contact: urethra, rectum, and throat.
For men who have sex only with women, routine chlamydia and gonorrhea screening isn’t broadly recommended at low risk, but it is encouraged if you’re under 29, have a new partner, or visit a sexual health clinic. Syphilis screening is recommended for men with risk factors like multiple partners, a history of incarceration, or living in a high-prevalence area. Hepatitis C screening is recommended for all adults over 18.
Getting Tested Is Simple
You can get STI testing at your primary care doctor, a sexual health clinic, a community health center, or through at-home test kits that let you collect samples and mail them to a lab. When you go in, be honest about your sexual history, including oral and anal sex, because that determines which tests and which body sites need to be checked. Most results come back within a few days. The common bacterial infections (chlamydia, gonorrhea, syphilis, trichomoniasis) are all curable with treatment, and viral infections like herpes and HIV are manageable with medication when caught early.