A genital lesion is any abnormal change on or around the genitals, including sores, bumps, blisters, rashes, or discolored patches of skin. These changes can appear on the penis, scrotum, vulva, vaginal area, or around the anus. Some are caused by sexually transmitted infections, but many have nothing to do with sexual activity at all. The term “lesion” is broad on purpose: it covers everything from a tiny painless bump to an open ulcer.
Types of Genital Lesions by Appearance
Not all genital lesions look the same, and their shape and texture often point toward different causes. Understanding the basic categories can help you describe what you’re seeing to a healthcare provider.
A macule is a flat, discolored spot that you can see but not feel with your fingertip. It’s typically smaller than 10 mm across. A papule is a small raised bump, also under 10 mm, that you can feel when you touch it. A vesicle is a small fluid-filled blister, characteristic of herpes infections and allergic skin reactions. A pustule looks like a vesicle but contains pus instead of clear fluid, and it’s common in bacterial infections or inflamed hair follicles. An ulcer is an open sore where skin has broken down, which is what you’d see with syphilis, chancroid, or a ruptured herpes blister.
Genital lesions can also take the form of wart-like growths, cysts beneath the skin surface, or white, thickened patches. They may appear alone or in clusters, and they range from completely painless to intensely tender.
Sexually Transmitted Causes
Several STIs cause visible changes on the genitals, and they look and feel quite different from one another.
Herpes (HSV-1 and HSV-2)
Genital herpes typically produces clusters of small, fluid-filled blisters that break open into shallow, painful ulcers. The first outbreak tends to be the most severe and can come with flu-like symptoms. Recurrent outbreaks are usually milder. Antiviral medications can shorten episodes and reduce how often they come back, but the virus stays in the body permanently.
Syphilis
Primary syphilis starts as a firm, painless ulcer called a chancre, usually 0.5 to 2 cm across, appearing at the spot where the bacteria entered the body. It often shows up on the glans of the penis or the vulva. The key feature is that it doesn’t hurt, which means people frequently miss it. A syphilis chancre heals on its own in 4 to 6 weeks, but that doesn’t mean the infection is gone. Without treatment, syphilis progresses to more serious stages. In 2024, there were over 190,000 total syphilis cases reported in the United States, a number that’s 42% higher than five years earlier.
Chancroid
Chancroid causes painful ulcers with soft, ragged edges, typically ranging from about 3 to 5 millimeters in diameter. It starts as a small raised bump that breaks down into an open sore within a day or two. Unlike syphilis, chancroid sores hurt significantly and may produce a yellowish discharge. Without antibiotics, these ulcers can persist for weeks to months.
HPV (Genital Warts)
Certain strains of HPV cause flesh-colored, raised growths that may appear singly or in clusters with a cauliflower-like texture. They’re usually painless. Other HPV strains don’t cause visible warts but can lead to cellular changes that increase cancer risk over time.
Molluscum Contagiosum
This viral infection produces small, firm, dome-shaped bumps that are white, pink, or skin-colored, often with a characteristic dimple in the center. They range from pinhead to pencil-eraser size. When they appear around the genitals, penis, vulva, or anus, they’re generally considered sexually transmitted. The bumps can become itchy, sore, or swollen.
Non-Sexual Causes
Many genital lesions have nothing to do with STIs. This is an important point, because the assumption that a genital bump must mean an infection causes a lot of unnecessary anxiety.
Contact dermatitis is one of the most common culprits. Soaps, detergents, latex, lubricants, or fragranced products can irritate the sensitive genital skin, causing redness, itching, and sometimes blistering that looks alarming but resolves once the irritant is removed.
Lichen sclerosus is a chronic skin condition that creates white, thin, wrinkled patches on the genitals. It’s linked to autoimmune processes. More than a quarter of people with lichen sclerosus also have another autoimmune condition, most commonly thyroid disease. Over time, if untreated, it can cause significant scarring that leads to urinary problems, painful sex, or restricted movement of genital tissue.
Cysts are another frequent finding. Bartholin’s cysts, sebaceous cysts, and vestibular cysts can all form in the genital area. They’re typically round, smooth lumps under the skin that may or may not be tender. Most are harmless, though they occasionally become infected and need drainage.
Other non-infectious possibilities include psoriasis, lichen simplex chronicus (thickened skin from chronic scratching), ingrown hairs, and folliculitis from shaving or friction.
How Genital Lesions Are Diagnosed
Because so many conditions look similar, a visual exam alone often isn’t enough. Diagnosis typically involves a combination of approaches depending on what the lesion looks like.
For suspected herpes, a nucleic acid amplification test (NAAT) or viral culture from the sore itself is the standard. Blood tests can also check for herpes antibodies and distinguish between type 1 and type 2. For syphilis, blood testing is the primary method, sometimes combined with direct examination of fluid from the sore. If a lesion looks unusual or doesn’t respond to initial treatment, a small tissue biopsy with specialized staining can help pin down the cause.
Getting tested matters even when a sore doesn’t hurt. Painless lesions aren’t necessarily harmless. A syphilis chancre is painless, and so are many HPV-related growths.
How Long Genital Lesions Take to Heal
Healing timelines vary enormously depending on the cause. A syphilis chancre resolves in 4 to 6 weeks even without treatment, though the underlying infection remains. Chancroid sores, by contrast, can linger for months without antibiotics. Herpes blisters from a first outbreak may take two to four weeks to heal, while recurrent episodes are shorter, especially with antiviral treatment. Some bacterial infections require at least three weeks of antibiotics, continuing until all lesions have completely closed.
Non-infectious causes follow their own patterns. Contact dermatitis usually clears within days to a couple of weeks once the trigger is avoided. Lichen sclerosus is a long-term condition that can be managed but not cured, requiring ongoing treatment to prevent scarring and flare-ups.
Signs That Need Prompt Attention
Any new genital sore you can’t explain deserves evaluation, but certain features suggest you should be seen sooner rather than later. Fever or pelvic pain alongside genital sores can indicate a systemic infection. A lesion that changes in size, color, or shape over time warrants a closer look to rule out precancerous or cancerous changes. Vaginal or penile bleeding that accompanies sores, swollen lymph nodes in the groin, or sores that don’t heal within a few weeks are all reasons to move up your timeline for getting checked.