Condition

Seborrheic Keratosis

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.
Dr. Schwarz, MD · Board-certified dermatologistLast reviewed September 8, 2026

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Seborrheic keratoses are benign. They never turn into cancer, most adults have collected several by their sixties, and a confirmed one needs nothing done to it. But I cannot tell from a description that yours is one, and melanoma is sometimes mistaken for a seborrheic keratosis, so have a new dark growth examined once before you freeze it, pick it, or buy a removal kit. Anything that is growing, changing color, bleeding on its own, itching persistently, or that simply looks unlike your other spots should be seen rather than watched.

— Dr. Schwarz, Board Certified Dermatologist

Key Facts

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How commonExtremely common - most people develop them with age, and by the seventies they are close to universal
Who gets itAdults, usually from the forties onward. Strongly influenced by family history. Small ones can appear much earlier
Curable or managedIndividual growths can be removed permanently. New ones continue to appear over time
Prescription neededNo treatment is needed at all. Removal is a minor in-office procedure and is usually considered cosmetic
Time to improveRemoval is done in one visit. The treated spot heals over one to three weeks

What It Is

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A seborrheic keratosis is a benign pile-up of ordinary skin cells on the surface. Keratosis means that build-up of keratin, the protein skin is made of. Seborrheic refers to the slightly greasy look some of them have and is misleading - they have nothing to do with oil glands or oily skin.

They look stuck on, like wax or a small barnacle pressed onto the skin. That is the most useful clue. The edge is sharply defined, the surface rough, warty or crumbly, the color pale tan through brown to almost black. They can be flat or raised, from a couple of millimeters to a few centimeters, and they favor the chest, back, face, neck and scalp.

Several looks are all the same thing. Flat light brown ones pass for a large freckle. Some are thick, dark and clearly raised. Some hang off a small stalk in a fold and get called skin tags. Small dark ones on the cheeks and temples, common on deeper skin tones, are a variant called dermatosis papulosa nigra. Rough white or gray ones on the lower legs and ankles are stucco keratoses.

They are not contagious, not viral, and nothing to do with hygiene. They come from age and genetics. If your parents had a lot, you probably will too.

What matters most is what they are not. This is not a precancer, it does not turn into skin cancer, and having dozens does not raise your risk. The only real risk is mistaking something else for one.

Symptoms

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Waxy and raised

Stuck-On Growth

A brown, tan or black growth with a rough, waxy surface that looks stuck onto the skin rather than growing out of it. They are harmless and become more common with age. Most people develop several.
A dull tan patch

Flat and Early

A flat or slightly raised tan patch with a fine, dry surface, most often on the face, chest or back. Early ones are easily mistaken for sun spots. They tend to thicken slowly over years.
Itchy, sore or bleeding

Irritated

A growth that catches on clothing, becomes red, sore or bleeds, or that itches persistently. Irritation is common and does not mean cancer. Any growth that changes quickly or looks different from the rest should still be examined.

How It Looks by Skin Tone

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Two growths on the upper back on fair skin. One is a flat light tan patch and the other is a raised mid-brown growth with a rough waxy surface and a sharply defined edge.A raised brown growth on the chest on medium olive skin. Its color is only slightly deeper than the surrounding skin, but the rough waxy surface and the sharply drawn edge are clearly visible.Several small, dark brown to black raised growths scattered over the cheek and temple on brown skin, ranging from one to three millimetres across, on otherwise even-toned skin.A cluster of black raised growths along the side of the neck on deep brown skin, each with a sharply defined edge, with two flat darker marks nearby where earlier growths were treated.
LightMediumBrownDeep

The variant that matters on deeper skin tones is dermatosis papulosa nigra - small dark brown to black raised growths on the cheeks, temples, forehead and neck, often starting in the twenties or thirties rather than middle age. They multiply over the years and run strongly in families. They are benign and need no treatment.

How they are removed matters, because this skin is not forgiving. Freezing is generally avoided on the face here - pigment-producing cells are sensitive to cold, and the pale spot left behind can be more noticeable and longer-lasting than the growth. Careful electrodesiccation with a fine tip, gentle curettage or scissor removal by someone experienced with deeper skin tones is more predictable. Ask for one or two test spots and come back in a few weeks to see how they healed before treating a whole area. Two aftereffects to plan for - a flat dark mark where the growth was, which usually fades over months, and a pale mark, which may not fully recover. Sunscreen on the treated area helps dark marks fade. Thickened or keloid scarring is a risk on the chest, shoulders and neck. One point on diagnosis. Here a seborrheic keratosis often looks dark or black without the reddish-brown tone textbooks describe, and melanoma - far less common - can also present differently, sometimes on the palms, soles and nail beds. Any new, changing or different-looking dark spot deserves the same examination regardless of skin tone. Being told skin cancer is unlikely is not the same as being examined.

Where It Shows Up

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Back view of a whole body with red marks across the upper, middle and lower back, both shoulders, the back of the neck and the head.
Back, chest, neck and scalp
They turn up mostly on the trunk, and the back usually carries the most. The neck and the scalp follow. They look stuck on, like a blob of wax sitting on the surface rather than growing out of the skin.
Front view of a head with red marks on both cheeks, both temples and both sides of the forehead.
Cheeks and temples
Small dark ones on the cheeks and temples are common on deeper skin tones, often from early adulthood and often running in families. They are harmless, and the reason to know the name is so they are not mistaken for moles.
Front view of a whole body with red marks under both breasts, around the waistline and down both shins and ankles.
Folds where clothing rubs, and the lower legs
They collect in folds where clothing rubs, such as under the breasts and at the waistband. Rough white or gray ones often scatter over the lower legs and ankles. They are not found on the palms, the soles or inside the mouth.

Causes

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Not fully worked out, but the main pieces are known.

Four things contribute, roughly in order. An inherited tendency - these run in families, often strikingly, and family history predicts how many you get far better than anything you do. Age - skin cells accumulate genetic changes over decades, and most of these growths appear from the forties onward. Changes in growth-signaling genes inside the skin cells themselves, such as FGFR3 and PIK3CA, which make a patch of cells thicken and pile up locally without becoming cancerous. And local factors including friction and, for some, sun exposure - they are more common on sun-exposed skin but also appear on skin that is rarely uncovered, so sun is not the whole story.

The build-up itself produces the appearance. Thickened keratin gives the rough, waxy surface and the sharp edge, small horn-filled openings give the pitted texture, and pigment trapped inside makes them brown or black.

Hormones may play a part, since crops can appear during pregnancy. Irritation changes how they behave rather than whether they form. None of this is something you caused or could have prevented.

Risk Factors

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Seborrheic keratoses come down to age and inheritance. Not diet, hygiene, skincare or any product.

Age
Age
The dominant factor. Uncommon before 30, frequent from the forties, close to universal by the seventies.
Inherited
Family history
Very strong. Someone whose parents had dozens will usually develop dozens.
Inherited
Skin type and ethnicity
The facial variant, dermatosis papulosa nigra, is far more common on deeper skin tones and often begins in early adulthood.
Sun & friction
Sun exposure
More common on sun-exposed skin, but they appear on covered skin too, so sun contributes rather than causes.
Sun & friction
Friction
Growths in folds - under the breasts, the groin, the waistband - are common and more likely to become irritated.
Hormones & health
Pregnancy
Crops are sometimes noticed during pregnancy, most likely from hormonal change.
Hormones & health
A sudden eruption of many at once
Reported alongside internal cancers. Debated, but worth being examined for.

Course

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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.

StartingYear 0
It begins as a flat tan patch

A flat, light tan patch appears, easily mistaken for a large freckle or an age spot.

ChestBackFace
ThickeningYears 1 to 5
It takes on the stuck-on look

The patch darkens and thickens, the edge sharpens, and the surface turns rough or waxy.

SettledYears onward
It reaches its size and stays there

It may darken slowly over years. It does not become cancerous and needs no monitoring beyond noticing change. More appear in the same areas, which is expected.

IrritationAny time
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.

After removalOne to three weeks
The spot scabs and heals

A treated spot scabs over one to three weeks, often leaving a flat mark darker or paler than nearby skin. Dark marks fade over months. Pale marks may be permanent.

What Makes It Better & Worse

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Four steps - an inherited tendency plus age, skin cells piling up into a stuck-on growth, pigment collecting in it, and irritation of a growth already there. Nothing you do controls the first three - step four is yours, along with making sure the growth has been correctly identified.

1An inherited tendency and age

What helps

  • A full skin check with many growths One odd growth hides among fifty.

What makes it worse

  • Age The biggest driver of how many you get.
  • Family history Why one person has one growth and another fifty.
  • A sudden crop of many new ones Many at once should be assessed.
  • Sun exposure Adds to the count, and darkens marks after removal.

2Skin cells piling up into a growth

What helps

  • Cryotherapy in clinic Quick for flatter growths, cautious on deeper skin tones.
  • Curettage or shave removal Precise, and it yields tissue to examine.
  • Electrodesiccation with a fine tip Shallow and controlled, good on the face.

3Pigment building up within that growth

What helps

  • Have a new growth examined once A dermatoscope settles most in seconds.
  • Watch for change, not for existence Growing, darkening, bleeding or newly itchy.
  • Ask for a test spot first See how one heals before doing twenty.
  • Daily sunscreen on treated areas Keeps the mark from deepening.

What makes it worse

  • Assuming a dark growth is benign Melanoma is mistaken for one.
  • Removal without a diagnosis Destroyed tissue cannot be analyzed.

4Irritation of a growth already there

What helps

  • Have irritated ones removed Easy when one keeps catching and bleeding.
  • Then leave it alone A confirmed growth needs no monitoring.
  • Plain petrolatum on the healing spot Keeps the scab soft, the scar neat.

What makes it worse

  • Picking or peeling one off They bleed, inflame, and mark.
  • Friction from clothing Straps, waistbands and belts irritate growths.
  • Shaving over them The usual cause of sudden bleeding.
  • Home freezing kits and acid pens They scar something nobody examined.

Over-the-Counter Products

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Everything here you can buy without seeing anyone.

Four ointments on white: CeraVe Healing Ointment, a Vaseline jar, a petroleum jelly tube and Aquaphor16:9 hero for Petrolatum. Never cropped: the tone strip and the corner logo depend on the full frame.
Limited evidence
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.
Four mineral sunscreens on white: Native SPF 30, Thinksport SPF 50, Colorescience Flex and EltaMD UV Clear16:9 hero for Zinc Oxide. Never cropped: the tone strip and the corner logo depend on the full frame.
Limited evidence
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.
Five white jars of 40% urea cream lined up, several also listing 2% salicylic acid16:9 hero for Urea. Never cropped: the tone strip and the corner logo depend on the full frame.
Limited evidence
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.
Paula's Choice 2% BHA exfoliant, La Roche-Posay Effaclar cleanser and a CeraVe psoriasis cream pumpLabeled cutaway diagram of a single skin pore, headed Salicylic Acid. The epidermis is a brick-textured band across the top and the dermis is pink below it, with a yellow oil gland at the base of the pore and a small cluster of bacteria inside it. A single dark navy callout line points into the top of the pore: decreases dead cells in pore. There are no other callouts, so the drawing shows one effect where the other ingredient diagrams show two or three.
Weak evidence
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.
Home freezing and acid kits
Home freezing and acid kits
Never use
Freezing sprays and acid pens sold for warts are imprecise on a growth like this. They commonly leave a pale or dark mark more noticeable than the growth was, and on the face they can scar. They also destroy the tissue, so if the growth turns out not to be what you assumed, there is nothing left to examine.

Prescriptions

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These need a prescription.

A white small dropper bottle on a white background, with a plain white label reading Eskata and a blue swoosh beneath it.
Hydrogen peroxide 40% (Eskata)
Limited evidence
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.

Procedures

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These are done in the office, usually over several visits.

16:9 hero for Shave Removal. Never cropped: the tone strip and the corner logo depend on the full frame.Diagram: how Shave Removal works in the skin
Strong evidence
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.
A gloved clinician treating a small dark spot on a patient's shoulder with a fine handheld instrument16:9 hero for Electrodesiccation and Curettage. Never cropped: the tone strip and the corner logo depend on the full frame.
Strong evidence
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.
16:9 hero for Cryotherapy (Liquid Nitrogen). Never cropped: the tone strip and the corner logo depend on the full frame.Diagram: how Cryotherapy (Liquid Nitrogen) works in the skin
Strong evidence
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.
16:9 hero for Skin Biopsy. Never cropped: the tone strip and the corner logo depend on the full frame.Diagram: how Skin Biopsy works in the skin
Strong evidence
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.
16:9 hero for Fractional CO2 Laser. Never cropped: the tone strip and the corner logo depend on the full frame.Diagram: how Fractional CO2 Laser works in the skin
Moderate evidence
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 to See a Dermatologist

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The point of being seen is identification, not treatment, and usually once per growth - being told by someone who looked through a dermatoscope that a growth is benign is what lets you stop worrying about it. Book for any new dark or raised growth you have not had examined, and sooner if one is changing: growing over weeks to months, darkening, developing a ragged edge, bleeding or crusting without being caught, turning itchy or sore, or looking unlike every other growth on your body. Book too if a growth keeps catching and inflaming, if you have so many you cannot tell what is normal for you, if you want some removed for appearance, or promptly if many new growths appeared over a short period. Method matters in one way - freezing or lasering a pigmented growth destroys the tissue so it can never be examined, so anything with a question attached should be scraped, shaved or cut off and sent to the lab.

— Dr. Schwarz, Board Certified Dermatologist

Complications

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Lookalikes

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Melanoma

This is the reason a dark growth gets examined. Both can be brown to black and raised, and a melanoma can be smooth and stuck-on enough to pass for a harmless growth. Melanoma tends to have an uneven edge, more than one color within it, and to change over weeks to months, while a seborrheic keratosis usually looks like several others you already have. A dermatoscope settles most of these in seconds, and that is why nothing dark should be frozen or burned off before someone has looked at it.

Sun Spots (Solar Lentigines)

Early seborrheic keratoses are flat and tan, which is exactly what a sun spot looks like, and the two often sit side by side on the same chest or hand. A sun spot stays completely flat and smooth and is confined to sun-exposed skin. An early growth slowly thickens, takes on a dry or waxy surface you can feel with a fingertip, and can appear on skin that is rarely uncovered.

Warts

Both can be raised and rough, and a warty-surfaced growth is easy to call a wart. A wart is caused by a virus, so it can spread to other spots and to other people, and it is usually skin-colored or gray with tiny dark dots in the surface. A seborrheic keratosis is a build-up of your own skin cells, is often brown or black, and cannot be caught or passed on. Treating one as the other with a wart kit is a common way a growth gets scarred.

Myths

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  • "A seborrheic keratosis can turn into melanoma." It cannot. It is benign and stays benign. The concern runs the other way - melanoma can be mistaken for a seborrheic keratosis, so a new or changing dark growth should be examined.
  • "Having a lot of them means I am at higher risk of skin cancer." The number you have does not raise your risk. It does make the one different growth harder to spot, which argues for a skin check rather than alarm.
  • "They are caused by a virus and are contagious, like warts." They are not. Warts come from human papillomavirus and spread. Seborrheic keratoses are your own skin cells piling up, driven by age and genetics, and cannot be passed on.
  • "They are caused by oily skin, or by not cleaning properly." The name is misleading. Seborrheic describes the greasy look of some of them, not their cause. They have nothing to do with oil glands, diet or hygiene.
  • "They are only caused by sun damage." Sun contributes, and they are more common on exposed skin, but they appear where skin is almost never uncovered too. Age and family history matter more.
  • "I can freeze or burn it off at home like a wart." Home kits are imprecise and they scar, and the mark is often more noticeable than the growth. Worse, they are used on something nobody has examined, which destroys the evidence.
  • "If it bleeds, it must be cancer." Not necessarily. One caught on a strap or a razor bleeds readily and looks alarming. Bleeding with no obvious knock is a reason to be seen.
  • "Once one is removed it will grow back." A properly removed growth generally does not come back in that spot, though a shallow removal can leave some behind. New growths nearby are new ones, not the old one.

Questions Patients Ask

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Could this be melanoma?

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.

Why am I suddenly getting so many?

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.

Does removing one stop more from appearing?

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.

Will removal leave a mark?

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.

Mine got red and itchy and started bleeding. What happened?

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.

Can I have them all removed?

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.

References

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