Syphilis on a man typically starts as a single, painless sore on or around the genitals, but its appearance changes dramatically as the infection progresses through distinct stages. Recognizing what each stage looks like can mean the difference between catching the infection early, when a single round of treatment clears it, and letting it advance to stages that cause serious damage.
The First Sign: A Painless Sore
The earliest visible sign of syphilis is a sore called a chancre (pronounced “SHANG-kur”). It appears at the spot where the bacteria entered the body, most commonly on the head of the penis, the shaft, or around the anus. It can also show up on the scrotum, lips, tongue, or inside the mouth or throat.
What makes a chancre distinctive is how unremarkable it can seem. It’s usually a single, round, firm sore with clean, raised edges. The surface is often smooth or slightly raw, resembling a small open ulcer. It is typically painless, which is the main reason many men never notice it or dismiss it as something minor. The sore is usually between one and two centimeters across, though it can be smaller.
A chancre appears anywhere from 9 to 90 days after exposure, with most showing up around two to three weeks after contact. Left alone, it heals on its own in about four to five weeks. This self-healing is deceptive: it doesn’t mean the infection is gone. The bacteria have simply moved deeper into the body.
How a Chancre Differs From Herpes or Ingrown Hairs
A syphilis chancre is easy to confuse with other genital bumps, but a few details help separate them. A chancre is firm to the touch, usually single, and painless. Herpes sores, by contrast, typically appear as clusters of small, fluid-filled blisters that are painful or itchy. They often burn or tingle before they appear and tend to recur in the same area.
Ingrown hairs produce a red, tender bump that looks like a pimple and usually has a visible hair at the center or just below the surface. They’re painful when pressed and tend to appear in areas that are shaved or experience friction. A chancre has none of those features: no pus, no visible hair, no tenderness.
That said, syphilis can present atypically. Some men develop more than one sore, or the sore may appear in a hidden location like inside the urethra or deep in the anal canal, making it invisible without a medical exam. If there’s any uncertainty, a blood test is the only reliable way to confirm or rule it out.
The Secondary Stage Rash
If the primary sore goes untreated, secondary syphilis develops roughly 6 to 12 weeks after the initial infection. This stage produces a rash that can cover the entire body in a symmetrical pattern. The rash is pink or dusky red and made up of circular, slightly raised spots. It is not itchy, which is unusual for a widespread rash and another reason people sometimes ignore it.
The hallmark of a secondary syphilis rash is its appearance on the palms of the hands and the soles of the feet. Most common rashes don’t show up in these locations, so spots on your palms or soles alongside a body-wide rash is a strong signal. The spots may have a thin, flaky scale on the surface, which sometimes leads to a misdiagnosis of psoriasis or other skin conditions.
Moist Sores and Mouth Patches
Secondary syphilis can also produce moist, raised growths in warm, damp areas of the body. These appear most often around the anus, inner thighs, or groin folds. They have a smooth or slightly bumpy surface and a grayish-white color. They look similar to genital warts but tend to be flatter, smoother, and wider at the base. These growths are highly contagious.
Inside the mouth, secondary syphilis can cause shallow ulcers and flat, white patches on the inner lips, tongue, or cheeks. These mucous patches are soft and painless, which again makes them easy to overlook. Some men also experience patchy hair loss on the scalp during this stage, sometimes described as a “moth-eaten” pattern where small irregular patches of hair fall out.
General symptoms during secondary syphilis can include fever, swollen lymph nodes, fatigue, sore throat, and muscle aches. These feel a lot like a flu or viral illness, which is one reason syphilis has historically been called “the great imitator.” The rash and other symptoms resolve on their own within weeks to months, but again, the infection is still active.
The Latent Stage: No Visible Signs
After the secondary stage clears, syphilis enters a latent phase where there are no visible symptoms at all. A man can carry the infection for years without any outward sign. The only way to detect latent syphilis is through a blood test. This stage can last indefinitely, and some people never progress further. Others, however, move into the most dangerous phase.
Late-Stage Syphilis and Gummas
Tertiary syphilis can develop years or even decades after the original infection if it was never treated. At this stage, the infection causes serious internal damage. On the skin, the most recognizable sign is a gumma: a soft, tumor-like growth made up of dead and swollen tissue. Gummas can appear on the skin, bones, liver, brain, heart, eyes, or testicles. On the skin, they look like firm nodules or lumps that may break down into ulcers.
Testicular gummas deserve specific mention for men. They can cause swelling or a noticeable mass in one or both testicles, which may be mistaken for testicular cancer. Late-stage syphilis can also affect the brain and nervous system (neurosyphilis), causing headaches, difficulty coordinating movement, numbness, vision changes, or personality shifts. It can damage the heart and major blood vessels as well. These complications are largely preventable with early treatment.
Getting Tested
Syphilis testing involves a blood draw. The standard approach uses two types of blood tests: one that detects general markers of infection and a second, more specific test that confirms whether the bacteria that causes syphilis is responsible. In early primary syphilis, blood tests can sometimes come back negative because the body hasn’t produced enough antibodies yet. If you have a suspicious sore but a negative result, retesting a few weeks later is standard practice.
Rapid tests that use a finger-prick blood sample are also available in some clinics and public health settings, offering results in minutes. Testing is recommended for anyone with signs or symptoms suggestive of syphilis, anyone who has had sexual contact with a person diagnosed with syphilis, and men who have sex with men, who face higher rates of infection.
Because syphilis sores are painless and the rash can be subtle, many cases are caught through routine screening rather than symptom-driven visits. If you’re sexually active with new or multiple partners, periodic screening is the most reliable way to catch an infection before it progresses.