A wart that looks black is usually showing off its own blood supply, which is nothing dangerous. Darkening also tends to happen when a wart is being destroyed, whether by a treatment or by the body’s own defenses. A few dark spots that look like warts are something else entirely, which is why a change you can’t explain deserves a look.1PubMed Central. Acral lentiginous melanoma: Basic facts, biological characteristics and research perspectives of an understudied disease
Why Warts Have Black Dots
Warts grow with their own small blood vessels running up into the thickened skin. Some of those tiny vessels swell and clot near the surface, and they show up as black dots. Doctors treat them as a telltale sign of warts.2Consultant for Pediatricians. Periungual Warts Under magnification, common warts show black and brown dots over a whitish background.3PubMed Central. Dermoscopy of Infectious Dermatoses (Infectiouscopy) in Skin of Color – A Systematic Review by the International Dermoscopy Society “Imaging in Skin of Color” Task Force
You can often see the dots yourself. Soak the skin first, then look closely in good light or with a magnifier. On the sole, the dots often sit in the middle of a hard, callus-like patch. Skin lines usually run around a wart rather than through it. If the top is pared, pinpoint bleeding reflects the same vessels.
Scattered dots are a stable, everyday feature of most warts, and they don’t mean the wart is dying or spreading. People sometimes call them seeds, though nothing is growing from them. Dots on a smooth, flat dark patch are not the wart pattern and deserve a closer look.
Because the dots are clotted vessels inside the skin, scratching them out doesn’t remove the wart or its virus. Picking can make the spot bleed and open the skin, which gives the virus a way into nearby skin and invites infection.
Some warts are brownish or dark throughout for another reason: they carry extra skin pigment.4PubMed. Pigmented viral warts: a clinical and histopathological study including human papillomavirus typing Pigment-making cells in these warts release more melanin into the surrounding skin cells.5PubMed. Pigmented viral warts: a clinical and histopathological study including human papillomavirus typing This pattern has been seen with certain wart virus types.6PubMed. A case of a human-papillomavirus-60-induced wart with clinical appearance of both pigmented and ridged warts An evenly dark, rough wart that has looked that way since it appeared is often just a pigmented wart, though any change in it still deserves a look.
When a Whole Wart Turns Black
When a wart turns black over a day or two, the color comes from bleeding and clotted blood trapped in the top skin layer. The vessels feeding the wart have clotted, so its tissue starves and its cells die. This often follows freezing, acid treatment, or pressure and rubbing.
The immune system can cause it too. Warts can blacken and then go away on their own when the body finally mounts an attack on the virus. A sore, red, swollen wart may come shortly before this, and nearby warts may darken and clear as well. Many warts disappear without ever turning black, though, so a lack of color change doesn’t mean a wart won’t clear.
In the first day or two the color can range from deep purple to black, because trapped blood changes color as it clots and dries. The surface often feels harder and drier than before, and the wart may look flatter as the dead tissue shrinks. Tenderness is common for a short while, especially on the sole, where body weight presses on it. The wart then dries into a dark, scab-like crust, and over one to a few weeks it loosens and falls away, and healthy pink skin underneath should heal smoothly.
After freezing, at home or in a clinic, a blister is an expected reaction, and it is sometimes blood-filled and dark. Black after freezing usually means the treatment reached the wart. Keep the area clean and covered while it heals.
A wart that darkens after you just treated it, or pressed on it for hours, is most likely responding to that injury. One that darkens with no trigger can still be the immune system at work; the clue is that it dries, crusts, and shrinks rather than spreading.
Black doesn’t always mean gone. Virus can remain in surrounding skin even after the dark part sheds, and if a rough bump returns at the same spot, the wart has regrown. Repeat treatment is common before a wart clears fully.
If the dark area isn’t shrinking or crusting after several weeks, or keeps spreading, it is no longer following the usual pattern and should be looked at. Darkness that remains after the wart has fully shed means something other than the wart may be there.
What to Do While It Heals
Never pick, cut, or clip off a wart yourself, even once it has turned black. This rarely fixes the wart and can cause pain and raise the risk of serious infection.7Joel D Foster DPM PC. Answering Your Plantar Warts FAQs
Daily care is simple. Wash gently with soap and water and pat dry. If the spot rubs in your shoes, cover it with a bandage or padding. Pause home acid or freezing products while the area is raw, and wear footwear in shared showers to avoid spreading the virus.
If the crust begins to lift at the edges, let it come off during normal washing or after a soak, rather than pulling it. If a flap catches on socks or shoes, cover it with a bandage.
The wart virus spreads by contact with infected skin, so wash your hands after touching or bandaging the area. Keep towels, nail clippers, and pumice stones used on the wart separate from other people’s, since these can carry the virus.
Watch for signs of infection: spreading redness or warmth around the wart, pus, worsening swelling, or pain that grows instead of easing. Red streaks or fever need prompt medical care.
People with diabetes or poor foot circulation should not self-treat foot warts. These groups do better with a doctor guiding treatment.8PubMed Central. Treatment of Multiple Recalcitrant Warts in an Immunocompromised Patient Using Purified Protein Derivative (PPD) Injection: A Case Report
Dark Spots That Aren’t Warts
Repeated pressure on the heel or sole can cause tiny bleeds under thick skin, which can be mistaken for a wart.9Dermatology Advisor. Talon noire Those specks tend to line up in streaks, while wart dots are scattered.10Dermatology Advisor. Talon noire They often sit on a callus and fade as the skin grows out.
A friction bruise usually follows a clear cause, such as a long run, new shoes, or a hike, while a wart usually has no such story. Wart dots stay put, whereas bruise specks move and fade over several weeks.
Melanoma on the palms, soles, or nails, known as acral lentiginous melanoma, is often mistaken for a wart.11PubMed Central. Acral lentiginous melanoma: Basic facts, biological characteristics and research perspectives of an understudied disease At one cancer center, about a third of these melanomas, 18 of 53, were first misdiagnosed, including as warts.12PubMed. Acral lentiginous melanoma mimicking benign disease: the Emory experience
On palms, soles, and nails it often starts as a flat, painless dark patch, so people ignore it or assume it is a bruise or wart. It occurs in people of all skin tones, and in people with darker skin these are among the more common sites for melanoma, so don’t assume you aren’t at risk. Treating a suspected wart for months at home can delay a correct diagnosis.
Several clues point away from a wart: a flat brown-black patch rather than a rough raised bump, irregular edges or several shades of color, a dark streak running along a nail, and no skin roughness or dots combined with steady growth. A dark spot that is flat, spreading, or doesn’t look like a typical wart should be checked. A dated phone photo makes change easy to judge.
A dark line running along the length of a nail can come from a bruise after injury, and a bruise grows out toward the tip with the nail. A streak that stays, widens, darkens, or has pigment spreading onto the skin beside the nail should be examined promptly.
When to See a Doctor
Have a wart checked if it changes color, shape, or size quickly.13Marvel Foot and Ankle Centers. 6 Signs You Need to See a Podiatrist for Wart Treatment Though rare, a growth resembling a wart can be skin cancer.14Marvel Foot and Ankle Centers. 6 Signs You Need to See a Podiatrist for Wart Treatment
Some situations call for quicker care: a black area with spreading redness, pus, or fever; darkness that stays after the wart is gone; a wart under or around a nail that blackens without treatment; and any foot wound in someone with diabetes.
At the visit, the doctor is checking for a wart’s typical features: a rough surface, interrupted skin lines, and black dots. A handheld magnifier with light can show the pattern of dots and vessels without any cutting. Bring photos showing how the spot changed.
If the features don’t fit a wart, the safe path is to sample the spot and look at it under a microscope. A small biopsy is usually done with local numbing, so you feel a pinch from the injection and little afterward. A small piece or the whole spot is removed and sent to a lab, and results usually take days to a couple of weeks. A biopsy is how a doctor tells a harmless wart from something more serious.
If the wart keeps coming back, a doctor can offer stronger freezing or other treatments, and combining treatments often works better for stubborn warts. If home products have failed for months, ask about those options.