Painful urination (dysuria) — a burning or stinging when you pee — is a classic sign of several sexually transmitted infections. The usual STI culprits are chlamydia, gonorrhea, and trichomoniasis, with genital herpes causing it when sores sit near the urethra. A urinary tract infection often causes the same burning, so a test decides which one it is.
often silent; discharge or burning if anything
discharge and burning; can also hit throat/rectum
frothy, itchy discharge with an odor
painful blisters that crust over; tends to recur
| Item | Value |
|---|---|
| Chlamydia | curable — often silent; discharge or burning if anything |
| Gonorrhea | curable — discharge and burning; can also hit throat/rectum |
| Trichomoniasis | curable — frothy, itchy discharge with an odor |
| Genital herpes | managed — painful blisters that crust over; tends to recur |
Which STIs cause painful urination (dysuria)?
Four infections account for most STI-related dysuria. Each has a tell-tale pattern, but those patterns overlap enough that none is reliable on its own, and several of these infections are frequently silent. Testing settles the question.
Chlamydia
Chlamydia is caused by the bacterium Chlamydia trachomatis; most US genital infections come from serovars D–K CDC Chlamydia. Roughly three quarters of infected women and half of infected men have no symptoms at all. When symptoms do show up, they usually appear within one to three weeks after exposure. In women, the burning on urination often comes alongside abnormal vaginal discharge; if the infection spreads upward, it can cause lower abdominal or low-back pain, fever, pain during intercourse, and bleeding between periods. Because so many cases are asymptomatic and reinfection is common, retesting after treatment matters — see chlamydia reinfection for why a follow-up test is part of the plan.
Gonorrhea
Gonorrhea is caused by Neisseria gonorrhoeae, which can infect the genitals, rectum, and throat CDC Gonorrhea. In men, the burning when urinating is often paired with a white, yellow, or green penile discharge, and less commonly with swollen, painful testicles (a sign the infection has reached the epididymis, the tube behind the testicle that stores sperm and can affect fertility if inflamed). In women, most have no symptoms; when they do, the picture is painful or burning urination, increased vaginal discharge, and bleeding between periods. A discharge that's thicker or more colored than usual leans toward gonorrhea, but that's not proof. The gonorrhea test confirms it.
Trichomoniasis
Trichomoniasis is caused by the protozoan parasite Trichomonas vaginalis and is the most common curable STI CDC Trichomoniasis. About 70% of infected people have no signs or symptoms at all. When symptoms appear — typically 5 to 28 days after infection, though sometimes much later — women may notice itching, burning, redness or soreness of the genitals, discomfort urinating, and a clear, white, yellowish or greenish discharge with a fishy smell. Men are commonly asymptomatic, but can get itching or irritation inside the penis, burning after urinating or ejaculating, and discharge. The fishy-smelling discharge is the most distinctive clue, though the parasite is easy to miss without a proper test — see trichomoniasis testing & diagnosis.
Genital herpes
Genital herpes is caused by two viruses, herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) CDC Herpes. Most people have no or very mild symptoms and don't know they're infected, and the majority of HSV-2 infections are undiagnosed. When herpes causes painful urination, it's usually because a sore sits on or near the urethra and urine stings the open lesion, rather than infection inside the urethra itself. A first outbreak brings blisters that break into painful sores taking a week or more to heal, often with flu-like symptoms — fever, body aches, swollen glands. Sores appear on or around the genitals, rectum, or mouth. Repeat outbreaks are shorter and milder, sometimes announced by a prodrome (a tingling or itching warning before lesions appear). If you're managing recurrences, alternative herpes treatments covers the options beyond standard antivirals.
When it's NOT an STI
Not every case of dysuria is sexually transmitted. The most common non-STI cause is a urinary tract infection (a bacterial infection of the bladder or urethra), which produces nearly identical burning along with frequency and urgency. Plain bladder irritation — from dehydration, certain soaps or products, or other sources — can do the same. To separate them, run a urine STI test alongside a urine culture. The STI panel finds chlamydia, gonorrhea, or trich; the culture finds the bacteria behind a UTI. One sample gives you two answers.
How to tell them apart
Usually you can't, at least not by symptoms alone. These infections overlap too much to tell apart by sight, and several are frequently silent, so what you feel doesn't map cleanly to a single cause. A few features lean one way or another: thick colored discharge points toward gonorrhea or chlamydia; a fishy-smelling discharge with itching suggests trich; visible painful blisters or sores point to herpes; and burning with urgency and frequency but no discharge or sores often means a UTI. These are leans. Because the symptoms overlap so much, only a test turns a guess into an answer.
Side-by-side comparison
| Cause | Type | Discharge | Other tell-tale signs | Often silent? |
|---|---|---|---|---|
| Chlamydia | Bacteria | Possible, abnormal | Burning on urination; pelvic pain if it spreads | Yes — most cases |
| Gonorrhea | Bacteria | White/yellow/green | Burning urination; swollen, painful testicles in men | Often, in women |
| Trichomoniasis | Parasite | Frothy, fishy-smelling | Genital itching, soreness, redness | Yes — about 70% |
| Genital herpes | Virus | Usually none | Painful blisters/sores; flu-like symptoms in first outbreak | Yes — most undiagnosed |
| UTI (not an STI) | Bacteria | Usually none | Urgency, frequency, no sores | Rarely silent |
How it's tested
A nucleic acid amplification test (NAAT) is the preferred method for chlamydia, gonorrhea, and trichomoniasis, and it works on a urine sample or a self-collected swab CDC STI Tx Guidelines, 2021. For gonorrhea, NAAT sensitivity is usually above 90% with specificity around 99% CDC Gonorrhea. For trich, the preferred NAAT (such as the Aptima assay) reaches roughly 95–100% sensitivity on vaginal swabs and female urine CDC Trich Tx. Herpes works differently — when you have a visible lesion, the test swabs the sore directly for type-specific virologic confirmation by NAAT or culture CDC Herpes Testing. In practice, testing means a urine sample, a self-collected swab, or a quick exam depending on what's suspected, and it's free or low-cost at health departments, Planned Parenthood, and Title X clinics, with results usually back in a few days. Here's how to get tested, and if your exposure was recent, check when to test after exposure so you don't test too early.
What to do next
If you have painful urination, get a urine STI test plus a urine culture so you cover both the STI and UTI possibilities at once. Avoid sex until you have results and, if needed, finish treatment. Chlamydia, gonorrhea, and trichomoniasis are all curable with the right medication, and herpes is managed with antiviral therapy. Don't share or skip doses, and make sure any recent partners get tested too.
Red flags — when to get seen urgently
Some symptoms shouldn't wait for a routine appointment. Get seen promptly if you have any of the following alongside painful urination:
- Fever, chills, or lower abdominal or low-back pain — these can signal the infection has spread to the upper reproductive tract.
- Swollen, painful testicles, which can point to epididymitis (inflammation of the tube behind the testicle that can affect fertility).
- Inability to urinate, or blood in the urine.
- A first herpes outbreak with widespread painful sores and flu-like illness, which is when symptoms tend to be most severe.
- Pregnancy with any of these symptoms, since several of these infections can affect the pregnancy.