Warts are firm, rough growths caused by a common virus that infects the top layer of skin. They are harmless and most of them clear on their own, but they spread easily and they are slow to treat. A seborrheic keratosis is a common, harmless growth that looks stuck onto the skin, like a piece of wax or a small barnacle. They are not cancer and they do not become cancer. The reason to see a doctor is to be sure that is what you are looking at.
The same eight facts on every condition comparison.
They are caused by HPV.
Cutaneous warts are benign growths caused by certain types of human papillomavirus.
They spread by contact.
Warts can pass through direct contact or from one area of skin to another.
Many clear on their own.
Many resolve naturally, especially in children.
Diagnosis is usually visual.
Clinicians look for the rough surface and small capillary dots; uncertain growths may be biopsied.
It is a benign growth.
Surface skin cells form a waxy, warty or stuck-on growth.
Color varies.
It can be tan, brown, gray or almost black.
It is not a precancer.
These growths become more common with age.
Uncertain lesions are tested.
Tissue is examined before any destructive treatment if the appearance is unclear.
Common warts Rough bumps on hands and fingers.
Plantar warts Flat, painful warts on the soles.
Flat warts Small, smooth, flat-topped bumps.
Filiform warts Long, thread-like growths on the face.
Classic seborrheic keratosis Raised, waxy, stuck-on growth.
Stucco keratosis Small white-gray bumps on the legs.
Dermatosis papulosa nigra Small dark bumps on the face.
Human papillomavirus enters through small skin breaks and stimulates local surface-cell growth. The thickened tissue forms a rough bump that may contain visible dark capillary dots.
A benign overgrowth of surface skin cells creates a localized plaque. Keratin and sometimes pigment collect in the growth, giving it a waxy, rough or stuck-on appearance.
Warts. Common in children and teenagers; adults can also develop them.
Seborrheic Keratosis. Usually appears in adult life and becomes increasingly common with age.
Warts are caused by the human papillomavirus infecting the top layer of skin. The virus makes skin cells grow faster, forming a rough bump.
Seborrheic keratoses are harmless growths of skin cells that become more common with age.
They often run in families.
Evidence labels come from each condition’s own treatment list.
The pharmacy sprays get nowhere near as cold as clinic liquid nitrogen, so they work best on small, new, thin warts on the hands and poorly on thick foot warts. They sting and can blister. On deeper skin tones they carry the same risk of leaving a pale or dark mark as clinic freezing does.
Covering a wart with tape for a few days at a time, then filing it, is cheap and harmless, and the trials are genuinely mixed on whether the tape itself adds anything. Any benefit is probably from the covering and the filing. It is reasonable alongside salicylic acid and a poor substitute for it.
The first treatment for almost every ordinary hand or foot wart, and the one with the best evidence outside the clinic. It dissolves the infected thickened skin a layer at a time, so it only works if it goes on every single day. Soak the wart for five minutes, file the dead surface off, apply, and cover it. Twelve weeks is a fair trial; ten days is not.
Wart treatments are often tried on these because the surface looks similar. Salicylic acid can thin the rough top layer, but it does not clear the growth, and it irritates the normal skin around it. The bigger problem is that it is usually being used on something nobody has examined.
A strong urea cream can soften and flatten the rough white growths that scatter over the lower legs, called stucco keratoses, if the roughness is what bothers you. It smooths the surface rather than removing the growth, and it has to be used continuously. It does nothing for thick, dark, stuck-on growths elsewhere.
This is aftercare, not treatment. A thin layer of plain petroleum jelly over a treated spot keeps the scab soft and gives the neatest healing, under a small dressing rather than an adhesive strip. It does nothing to a growth that is still there.
Daily mineral sunscreen over a spot that has just been treated stops the temporary mark from darkening and helps it fade faster, which matters most on the face, chest and hands. It will not remove a growth or stop new ones forming. Sun is only one of several things that drive these, and age and family history matter more.
Imiquimod cream. A cream that works on the last step of the problem: it makes the local immune system pay attention to the virus. It is used mainly for flat warts on the face and for warts that keep coming back, applied a few nights a week for weeks. It reddens and irritates the skin while it works, and it does poorly on thick foot warts.
A retinoid cream used for the flat warts that appear in groups of dozens on the face and the backs of the hands, where acid and freezing would be too harsh over so wide an area. It speeds up the turnover of the infected surface cells. It takes months, and it makes the skin dry and sun-sensitive while it runs.
5-fluorouracil cream. A chemotherapy cream at a low strength, applied to the wart itself, often under tape. It is used for flat warts and for warts that have not shifted with acid, and it is a common choice in children because it does not hurt going on. It reddens and can crust the treated skin, and it is not used in pregnancy.
A high-strength peroxide solution applied in clinic was approved for raised growths on the face and body. It cleared some growths, often needed repeat visits, and commonly caused stinging, crusting and pigment change. It was withdrawn from sale in the United States, so in practice removal is done by hand rather than with a liquid.
An old stomach-acid tablet that people ask about for multiple stubborn warts, on the idea that it nudges the immune system. The better-controlled trials found it no more effective than a dummy tablet in adults. It is safe and cheap, so it is occasionally still tried in children, but it should not replace treatment that is known to work.
Candida antigen injection. A tiny amount of yeast protein injected into one wart, to wake the immune system up in that spot. What makes it useful here is that untreated warts elsewhere on the body often clear at the same time, so it suits someone with many warts rather than one. It is repeated every few weeks, and it can cause a day or two of aching or flu-like feeling.
Bleomycin injection. Injected directly into warts that have resisted everything else, particularly thick ones on the soles and around the nails. Clearance rates are good. It is painful enough that the area is numbed first, it can leave a permanent nail change if used at the nail fold, and it is not used in pregnancy, so it sits late in the order for a reason.
Liquid nitrogen freezes the infected skin and the injury also draws immune attention to the spot. It needs repeating every two to four weeks, usually three or four times, and a wart regrowing from the edge between sessions is normal rather than failure. Over several months its results are broadly similar to salicylic acid used properly. It stings, it blisters, and on deeper skin tones it can leave a lasting pale or dark mark.
A blistering liquid painted on in clinic and washed off a few hours later. It is painless going on, which is why it is a common first choice for children and for warts on the face. The blister that follows lifts the infected skin away over the next few days and can be sore. It usually takes more than one visit.
Paring in clinic. The top dead layer is shaved off with a blade. It does not hurt, because that layer has no nerve supply, and it does two jobs at once: it confirms the diagnosis by exposing the tiny clotted vessels a callus does not have, and it lets acid or liquid nitrogen reach live infected skin. It is done alongside another treatment, never as the whole treatment.
The wart is numbed, burned with an electric current and scraped away in one visit. It is kept for a single stubborn wart that has failed everything gentler, because it leaves a scar, and a scar on the sole of a foot can hurt more than the wart did. Warts can still regrow at the edge of the scar.
The laser targets the small blood vessels feeding the wart rather than the virus itself. It is an option for stubborn warts on the hands and around the nails when freezing has not worked, and it spares the skin around it, which matters on the face. Several sessions are needed, results are inconsistent, and it is not usually covered by insurance.
A few seconds of liquid nitrogen makes flatter growths blister and lift off over a week or two, and it is the quickest way to treat several at once. It destroys the growth, so nothing can be examined afterward, which is why it is not used on anything with a question attached. It is used cautiously on the face and on deeper skin tones, because the pigment cells are sensitive to cold and it can leave a pale spot.
The growth is scraped off with a small curette and the base sealed with a fine electric tip. It is controlled and shallow, which is why it is often preferred for small facial growths and for the dark facial growths common on deeper skin tones. Scraping first still gives tissue that can be examined if there is doubt.
The growth is numbed and shaved off level with the skin in a few seconds. It is the method of choice when there is any question about what a growth is, because it produces tissue that can be sent to the laboratory. It leaves a flat mark that fades over months, and it does not stop new growths appearing elsewhere.
An ablative laser can vaporise a growth precisely and is sometimes used when several need treating on the face. Like freezing, it destroys the tissue, so it is only for growths already confirmed as harmless. It is the most expensive of the options and it is not better than a curette for a single growth.
When a growth is changing, bleeding on its own, or simply looks unlike your others, part or all of it is taken after numbing and examined under a microscope. It is the only way to be certain, and the threshold for doing it is deliberately low, because the cost of a small biopsy is trivial next to missing a melanoma. An irritated growth is one of the commonest reasons a benign growth ends up being sampled.
Warts are self-limiting — they end on their own eventually. In children, roughly two thirds clear within two years without treatment. Adults are slower, and warts present for several years are least likely to go quietly.
Seborrheic keratoses appear slowly, change slowly, then stay. Two departures deserve attention: one growth that starts changing - growing, darkening, bleeding on its own, or itching persistently - and a sudden crop of many new ones over weeks to months.
Spreading to new spots
An untreated wart seeds others nearby, so one bump becomes a ring of small ones around it, or a line of them along a scratch or a shaving path. Picking, biting and filing several warts with the same file are the usual ways it happens. Covering the wart, keeping your own file and treating early keep the number down.
Color change after treatment
Freezing, and any treatment that blisters or burns, works by injuring the skin, and injured skin can heal a different color. A pale ring around the treated spot can last a year or more and is sometimes permanent, and a dark mark can outlast the wart by months. Both are far more likely on deeper skin tones, which is why gentler treatment and a small test spot are often the better trade.
Warts around and under the nails
Warts that set up in the nail folds are the most stubborn of the group, because the nail shields the virus from creams and from freezing. Left long enough, a wart growing under the nail can lift it or leave a permanent ridge or split in the nail plate. Nail biting and picking at hangnails are how most of them start, and they are the ones most worth taking to a dermatologist early.
Catching on clothing makes it flare
A growth caught by clothing, a strap or a waistband can turn red, swollen, itchy, crusted or sore, and can bleed. That is an irritated seborrheic keratosis. It settles, but it looks alarming and often prompts removal or a sample.
Seek assessment for an uncertain, painful, bleeding or changing growth, or persistent warts with weakened immunity. Genital lesions need separate assessment.
Have a new, changing, bleeding or uncertain growth assessed; skin cancer can sometimes resemble a harmless stuck-on growth.
Almost nobody can say. The virus lives on warm wet surfaces and passes by skin contact and shared objects, and there is usually a gap of one to six months between catching it and seeing the wart. It is not a sign of poor hygiene.
Probably, eventually. About two thirds of warts in children clear within two years without treatment, and adults are slower. Treating is worth it because warts spread to other spots and other people meanwhile, and older ones are harder to clear.
Freezing removes infected skin but does not reach every infected cell, and it does not teach the immune system to recognize the virus. That is why it takes several sessions two to four weeks apart, and why a wart can regrow from the edge. Regrowth is normal, not treatment failure.
Yes, though not dramatically. The virus passes on shared towels, bath mats, razors, nail clippers and files, and through contact with broken skin. Keeping the wart covered, keeping your own towel and clippers, and wearing something on your feet in shared bathrooms covers most of the risk.
Related viruses, but not the same strains, and they do not usually move between those sites. Genital warts are assessed and treated differently, so do not manage them with hand-wart products.
No. A wart has no root to remove, so cutting reaches live skin without reaching all the virus, and you are left with a scar plus a wart growing back around it. It also risks infection and, on the foot, a wound that heals slowly. Paring is done in clinic with a sterile blade.
It could be, which is why it should be looked at rather than diagnosed at home. Melanoma is sometimes mistaken for a seborrheic keratosis, and a dermatoscope resolves most of these in seconds. The concerning features are change in size, shape or color, bleeding without being knocked, an irregular edge, and a growth unlike your others. Book rather than watch.
Age and family history account for nearly all of it. They accumulate steadily from the forties onward, and someone whose parents had many will develop many. A genuinely sudden crop over weeks to months, especially with itching, is different and worth examining.
No. Removal deals with that growth, not the age and inherited tendency behind it, so new ones can keep appearing elsewhere. That is expected, not a failed removal.
Often, at least for a while. A flat spot darker or paler than nearby skin is common, and dark marks usually fade over months. Pale marks can be permanent and are more noticeable on deeper skin tones, so ask about the method and do a test spot before treating a large area. Daily sunscreen on the treated spot makes a real difference.
Most likely it caught on clothing, a strap or a razor and became an irritated seborrheic keratosis. They look far worse than they are and they settle. Still have it looked at - an irritated growth is one of the harder ones to be sure about by appearance, and a growth that bled with nothing catching it is a different question.
As many as you and your doctor think sensible, usually in sessions rather than all at once. It is normally considered cosmetic, so ask about cost first. On the face, and particularly on deeper skin tones, start with a small test area and see how it heals.
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