Condition

Actinic Keratosis

An actinic keratosis is a rough, scaly patch caused by years of sun. It is a precancer, meaning it is the step before skin cancer rather than cancer itself. Most never progress, but most squamous cell carcinomas start as one, which is why they are treated.
Dr. Schwarz, MD · Board-certified dermatologistLast reviewed September 8, 2026
16:9 hero for Actinic Keratosis. Never cropped: the tone strip and the corner logo depend on the full frame.

Start here

These are not dry patches. They are the visible edge of thirty or forty years of sun damage, and we treat them for arithmetic rather than alarm - any single one is unlikely to become a cancer, but most people have twenty of them and keep making more. Freezing four patches on a forehead covered in them treats four, which is why creams and light treatments that cover a whole area often make more sense. Find them by touch - a small patch of sandpaper that keeps coming back in the same place is worth showing someone.

— Dr. Schwarz, Board Certified Dermatologist

Key Facts

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How commonVery common. One of the most frequent reasons adults see a dermatologist, and widespread in older adults with years of sun exposure
Who gets itMost often adults over 40 with fair skin that burns easily, and anyone who has spent years outdoors. More common in men, partly because of hair loss on the scalp
Curable or managedIndividual spots are treated and clear. The sun-damaged skin they come from is managed long term, and new ones are expected
Prescription neededNot always. Freezing in clinic needs no prescription. Creams for treating a whole area do
Time to improveA frozen spot heals over one to three weeks. Cream treatments run about two to four weeks, and the skin looks considerably worse before it looks better

What It Is

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An actinic keratosis is a small rough patch caused by long-term ultraviolet damage. It is easier to feel than to see - a dry, gritty, sandpapery area a few millimeters across that catches on a razor or a towel and keeps coming back in the same place.

They sit where sun has landed for decades - the forehead, temples, nose, ears, the bald or thinning scalp, the lower lip, the backs of the hands and the forearms. On lighter skin they are often pink or red with a yellowish or gray scale. On deeper skin tones they may be brown, gray or simply a slightly darker rough patch, and texture matters more than color.

They are called precancerous, and the word is worth being exact about. An actinic keratosis is not cancer. It is a patch where sun-damaged cells in the top layer have started multiplying abnormally without becoming a tumor. A minority become squamous cell carcinoma, and estimates of how often vary too widely to quote. The risk for any one spot in any one year is low.

They are treated anyway because of the other half of the picture. Most squamous cell carcinomas arise from an actinic keratosis or from the damaged skin around one, and people rarely have just one. Thirty rough patches, with new ones every summer, add up to real risk even though each spot is low risk.

Dermatologists call this field damage - the visible patches are the parts of a larger damaged area that have crossed a threshold. Freezing treats what you can see. Creams, photodynamic therapy and peels treat the whole field, including what has not surfaced yet.

There is also a version on the lower lip called actinic cheilitis - persistent dryness, scaling, cracking or a blurred lip border. It matters more than it looks: the lip is a higher-risk site.

Symptoms

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Rough Scaly Patch
Sandpaper spots you feel first

Rough Scaly Patch

A small dry patch that is easier to feel than to see, often described as sandpapery. It usually sits on the face, ears, scalp or backs of the hands, where sun exposure adds up over years. Patches may flake, come back, and never fully settle.
Red and Inflamed
Pink patches that sting

Red and Inflamed

A flatter pink or red patch with a fine scale on top, sometimes tender when scratched or shaved over. It can look like a stubborn patch of dry skin that never clears. Repeated soreness in the same spot is a reason to have it looked at.
Thick or Horn-Like
A hard raised growth

Thick or Horn-Like

A patch that has built up into a hard, raised lump, sometimes with a horn of packed keratin on top. Thicker lesions carry a higher chance of having changed into a skin cancer underneath. These are usually sampled rather than treated blind.

Where It Shows Up

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Front view of a head and neck with red marks across the top of the scalp, across the forehead, at both temples, on both cheeks, on both ears, on the nose, on the lower lip and on the front of the neck.
Head, face and neck
This is where most patches turn up, because it is where the sun has landed for decades: the bald or thinning scalp, the forehead and temples, the cheeks, the nose, the ears and the lower lip. The scalp, the ears and the lip are the three people forget to protect, and the lip and the ear matter more than the rest because a patch there carries higher risk if it does progress.
Front view of a whole body with red marks on both forearms, on the backs of both hands and on both shins. The rest of the body is clear.
Forearms, hands and lower legs
After the head, the backs of the hands and the forearms are the commonest place — the skin that has been outside a sleeve all your life. In women the lower legs are a frequent site too, often with many patches at once on the shins.
Back view of a whole body with red marks on the back of the neck, on both shoulders, on both forearms and on the backs of both hands. The rest of the body is clear.
Back of the neck and shoulders
The back of the neck and the tops of the shoulders take years of sun that nobody puts sunscreen on. In men whose hair has thinned the back of the neck is often as affected as the scalp, and the backs of the hands and forearms show from behind too.

What Happens in the Skin

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This is what is going wrong under the skin, in the order it happens. Click a step to see it.

How Actinic Keratosis happens
Skin basics
BARRIEREPIDERMISDERMIS0NORMAL SKIN1UV LIGHT DAMAGES SKIN CELL DNA2DAMAGED CELLS SURVIVE3A ROUGH SCALY PATCH BUILDS UP4A FEW PROGRESS TO SKIN CANCER

In skin that has had little sun, the cells of the outer layer carry undamaged DNA. They divide, rise to the surface and shed on a set schedule, so the skin feels smooth. Any cell too damaged to repair is cleared away before it can multiply.

Ultraviolet light is absorbed by the DNA inside the keratinocytes, the cells that make up the outer layer of skin, and every hour outdoors adds a little more damage to the total.

Most of that damage is repaired within hours, but over decades some of it lands on the genes that run the repair and shutdown system, and cells that should have been cleared away stay alive instead.

The surviving abnormal cells multiply inside the top layer of skin, thicken it and upset the way it sheds, and that disordered shedding is the gritty scale you can feel before you can see it.

In a small share of patches the abnormal cells fill the full thickness of the top layer and then break through into the deeper skin, which is squamous cell carcinoma. Almost everything on the lists below is pushing on this step, and treating a patch early is aimed at stopping it.

The outer film of dead cells and oil. It holds water in and keeps irritants out, and it is thinner than a sheet of paper. Almost every dry, itchy, stinging skin problem starts here.

The outer layer, and the only one anything in a jar reaches. It renews itself constantly: a cell made at the bottom takes about a month to reach the surface and flake off. Most of what a skincare product does, it does here.

The living layer underneath, holding the blood vessels, the nerves and the collagen. It is where lasting change happens and it is hard to reach: most of what is sold for the skin never gets this far.

The cause is ultraviolet light, accumulated over years. UVB is absorbed directly by DNA in keratinocytes, the cells of the outer layer of skin. Most of that damage is repaired within hours, and cells too damaged to repair are supposed to die off.

Over decades, some damage lands on the genes that control repair and shutdown, particularly p53. Once those controls are weakened, abnormal cells survive when they should not. They multiply within the top layer, thicken it, and disturb the way it sheds. The rough scale you feel is that disordered shedding.

At this stage the abnormal cells are confined to the outer layer. With further damage they can fill its full thickness, which is squamous cell carcinoma in situ, and eventually break through into the deeper layer, which is invasive squamous cell carcinoma.

Two things follow. The damage is cumulative - total lifetime exposure matters more than any single sunburn, though burns contribute. And the skin between the visible patches has had the same exposure, which is why new spots keep appearing after old ones are treated.

Tanning beds do the same damage, as does the ultraviolet in some medical light treatments over many years. A weakened immune system does not create the damage but removes the surveillance that clears abnormal cells, which is why transplant recipients get large numbers of them and progress more often.

Risk Factors

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A lifetime of exposure, and how much natural protection you have. Most were nobody's choice.

Sun exposure
Total lifetime sun exposure
The main factor. Everyday exposure counts as much as holidays.
Sun exposure
Outdoor work or outdoor hobbies
Farming, construction, fishing, roofing, gardening and golf damage the face, neck, forearms and hands.
Sun exposure
Living in a sunny climate or at altitude
More ultraviolet each year, and altitude raises it further.
Sun exposure
Tanning bed use
The same damage, delivered faster.
Sun exposure
A history of bad sunburns
Burns add to the total, though everyday exposure matters more.
Sun exposure
Hair loss on the scalp
Why men get more than women. Unprotected scalp takes full exposure.
Inherited
Fair skin that burns easily
Freckles and burns rather than tans, especially with red or blond hair and light eyes.
Inherited
Inherited conditions
Albinism and xeroderma pigmentosum bring these patches decades earlier.
Age
Age over 40
The damage takes decades to show, so the count climbs with age.
Other health conditions
A suppressed immune system
Transplant recipients and people on immune-suppressing medicines get far more of these, and more skin cancer. Ask about skin checks.
Other health conditions
Previous skin cancer
Or existing actinic keratoses. Skin that has crossed the threshold once.
Other health conditions
Long-term light-sensitizing medicines
Some antibiotics and diuretics make a given amount of sun do more damage. Ask your prescriber before stopping.

Course

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Actinic keratoses are not steady. Individual spots come and go, which is one reason they get dismissed. The trend over years is upward.

Weeks to monthsAppearing
A rough, gritty patch

A small area turns rough and gritty, usually noticed by touch while washing or shaving before it is visible.

OngoingComing and going
Patches flake off, then come back

Many flake off, look resolved for a few weeks, then return in the same place. Some do clear on their own, particularly with less sun.

Over yearsAccumulating
The number rises, and so does the damage around them

Someone who once had two may have twenty-five a decade later. The skin between them develops the same mottled color, fine broken vessels and thin crepe-like texture.

Warning changeSomething is different
A patch that changes needs a biopsy

A patch thickens, turns tender, itches persistently, bleeds, forms a hard horn, grows quickly or reaches more than about a centimeter. Those changes suggest it has progressed. In squamous cell carcinoma the cells fill the top layer and then break through into deeper skin, which takes years, and much less in anyone immune-suppressed.

After treatmentWhat follows
Treated spots heal, new ones are expected

Treated spots heal within a few weeks. New ones are expected, because the damage remains. Most people settle into periodic checks and occasional retreatment rather than a one-time fix.

What Makes It Better & Worse

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An actinic keratosis comes in four steps — ultraviolet light damaging DNA, damaged cells surviving instead of clearing, those cells building into a rough scaly patch, and a small share progressing to squamous cell carcinoma. Treatment interrupts it before step four.

What is driving yours?

FATBARRIEREPIDERMISDERMIS

Ultraviolet light is absorbed by the DNA inside the keratinocytes, the cells that make up the outer layer of skin, and every hour outdoors adds a little more damage to the total.

Most of that damage is repaired within hours, but over decades some of it lands on the genes that run the repair and shutdown system, and cells that should have been cleared away stay alive instead.

The surviving abnormal cells multiply inside the top layer of skin, thicken it and upset the way it sheds, and that disordered shedding is the gritty scale you can feel before you can see it.

In a small share of patches the abnormal cells fill the full thickness of the top layer and then break through into the deeper skin, which is squamous cell carcinoma. Almost everything on the lists below is pushing on this step, and treating a patch early is aimed at stopping it.

What helps

  • Daily broad-spectrum sunscreen SPF 30 or higher on face, ears, neck, scalp and hands.
  • A wide-brimmed hat and sleeves More reliable than sunscreen, no reapplying.
  • Lip balm with SPF Higher-risk site, and almost nobody protects it.
  • Nicotinamide 500 mg twice a day modestly reduces new patches in high-risk people.

What makes it worse

  • Continuing unprotected sun exposure Cumulative, and the biggest item here.
  • Skipping sunscreen on scalp and lips Exactly the sites people forget.
  • Tanning beds The same damage, concentrated.
  • Light-sensitizing medicines Make a given amount of sun do more damage.
  • Smoking Linked to lip damage and poorer healing.

What helps

  • Fluorouracil cream Treats what you cannot see as well as what you can. If you are pregnant or breastfeeding, ask the doctor managing your pregnancy first.
  • Imiquimod cream Prompts the immune system to clear abnormal cells, over a longer course. Same pregnancy advice.
  • Tirbanibulin ointment A short course, milder reaction, useful on face and scalp.
  • Photodynamic therapy A whole area in one or two visits, sore and red for days.
  • Chemical peels and curettage A peel covers a broad area, scraping handles thick patches.

What makes it worse

  • Treating only the spots you see New patches keep arriving from the skin around them.
  • A suppressed immune system Far more patches, and much more progression.
  • Stopping a cream treatment early The redness and crusting means it is working.

What helps

  • Freezing with liquid nitrogen Quick and effective for a few discrete patches.

What makes it worse

  • Treating them as dry skin Moisturizer softens the scale and leaves the cells alone.
  • Picking or filing off the scale It returns, because the problem is beneath it.

What helps

  • Biopsy anything that has changed Sampled, not frozen.
  • Periodic full skin checks How progression gets caught early.

What makes it worse

  • Ignoring a patch that has changed Thickening, tenderness or bleeding means biopsy.
  • Skipping follow-up skin checks Progression is found by looking.

How These Treatments Work

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Treatments for Actinic Keratosis do not all work in the same place. Tap one to see where it acts.

Pick a treatment
Skin basics
BARRIEREPIDERMISDERMISFREEZES THE CELLSCLEARS THE FIELDCLEARS THE FIELDSTOPS NEW DAMAGE

Treats the spots you can see, one at a time.

Treats the damaged cells you cannot see yet, across a whole area. It gets red before it gets better.

The same idea, done in the office in one visit with light.

The only thing that lowers how many form next year.

The outer film of dead cells and oil. It holds water in and keeps irritants out, and it is thinner than a sheet of paper. Almost every dry, itchy, stinging skin problem starts here.

The outer layer, and the only one anything in a jar reaches. It renews itself constantly: a cell made at the bottom takes about a month to reach the surface and flake off. Most of what a skincare product does, it does here.

The living layer underneath, holding the blood vessels, the nerves and the collagen. It is where lasting change happens and it is hard to reach: most of what is sold for the skin never gets this far.

Over-the-Counter Products

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Everything here you can buy without seeing anyone.

Broad-spectrum sunscreen SPF 30+
Broad-spectrum sunscreen SPF 30+
Always
The one thing that reduces how many new patches you make. Daily use on the face, ears, neck, scalp and backs of the hands has been shown to lower the number of new actinic keratoses and of squamous cell carcinomas, even in people who already have plenty. It does not clear the patches you already have, so it sits alongside treatment rather than replacing it.
Lip balm with SPF
Lip balm with SPF
Moderate evidence
The lower lip is the site almost nobody protects and one of the higher-risk places for a patch to progress. A balm with SPF 30 or higher, reapplied through the day, is the practical way to cover it. It will not treat a lip that is already persistently dry, scaly or cracked — that needs looking at.
Nicotinamide 500 mg twice a day
Nicotinamide 500 mg twice a day
Moderate evidence
An over-the-counter form of vitamin B3, taken as a tablet, which modestly reduced new actinic keratoses and new skin cancers in people at high risk. The effect is real but small, and it stops when the tablets stop. It is an add-on to sun protection and treatment, not a replacement for either. Check with your doctor before starting it.
Moisturizer alone
Moisturizer alone
Weak evidence
Moisturizer softens the scale and makes the patch feel smoother for a while, which is exactly why these get treated as dry skin for years. It does nothing to the abnormal cells underneath, so the patch returns in the same place. Filing or picking the scale off has the same problem, and can leave a sore.

Prescriptions

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These need a prescription.

A white cream tube lying on its side on a white background, with a plain white label reading Fluorouracil and a blue swoosh beneath it.
Fluorouracil cream (5-FU)
Strong evidence
The best-studied cream for treating a whole sun-damaged area rather than single spots, usually applied for two to four weeks. It attacks abnormal cells wherever they are, so it also clears patches that had not surfaced yet. The area becomes red, crusted and sore where those cells were, often revealing more than you knew you had — that reaction is the treatment working, and stopping early leaves the area half treated. If you are pregnant or breastfeeding, ask the doctor managing your pregnancy first.
A white cream tube lying on its side on a white background, with a plain white label reading Imiquimod and a blue swoosh beneath it.
Imiquimod cream
Strong evidence
Prompts your own immune system to clear the abnormal cells, applied a few times a week over a longer course than fluorouracil. It also treats the whole field, and it can suit the face and scalp well. Expect redness and crusting, and sometimes a few days of feeling fluey. The same pregnancy advice applies: ask the doctor managing your pregnancy first.
A white cream tube lying on its side on a white background, with a plain white label reading Tirbanibulin and a blue swoosh beneath it.
Tirbanibulin ointment
Moderate evidence
A newer ointment used once a day for five days on the face or scalp. The short course and the milder reaction are the point of it — most people are through the redness and flaking within a couple of weeks. It is used on a limited area at a time, and long-term results are less well known than for fluorouracil.
A white cream tube lying on its side on a white background, with a plain white label reading Diclofenac and a blue swoosh beneath it.
Diclofenac gel 3%
Limited evidence
An anti-inflammatory gel applied twice a day for two to three months. It is much gentler than fluorouracil, which makes it an option for people who cannot manage a strong reaction on visible skin. It clears fewer patches, and the course is long.
A plain white medicine tube lying at an angle on a white background, capped, labeled Tretinoin in black with a navy blue swoosh curving along its length.Diagram: how Tretinoin works in the skin
Weak evidence
A prescription retinoid people often ask about here, because it is known for sun-damaged skin. It smooths texture and helps the mottled color, but trials have not shown that it clears actinic keratoses or prevents skin cancer. It is reasonable for the look of sun damage, and it is not a treatment for the patches themselves.
An amber prescription bottle lying on its side on a white background with a plain white label reading Acitretin, and six small round white tablets spilled out in front of it.
Acitretin
Moderate evidence
An oral retinoid used mainly for organ transplant recipients and others whose immune systems are suppressed, who make large numbers of these patches and progress from them more often. It reduces how many new patches and skin cancers appear while it is taken, and the benefit fades once it is stopped. It has real side effects and needs blood tests. It must never be taken in pregnancy, and pregnancy has to be avoided for three years afterwards.

Procedures

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

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
Freezing with liquid nitrogen is the quickest option for a handful of separate patches, done in a few seconds each with no prescription. It stings sharply, then blisters or crusts and heals over one to three weeks. Its limit is that it only treats what can be seen, so new patches keep arriving from the damaged skin around them. It often leaves a permanently pale mark, which is more noticeable on deeper skin tones — worth asking about before you start.
A rectangular LED panel in a white frame, angled on a white background, its face filled with a dense grid of several hundred small blue lights all lit, casting a blue glow onto the surface beneath it.Diagram: how Photodynamic Therapy works in the skin
Strong evidence
A light-activated liquid is put on the whole area, left to soak in, then activated with a lamp. It treats a broad field in one or two clinic visits instead of weeks of cream, which suits people who cannot manage a long course at home. The area stings during treatment and is red, swollen and sore for several days, and the treated skin has to be kept out of light straight afterwards.
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.
Moderate evidence
The thicker, harder patches that freezing struggles with are scraped away under local anesthetic and the base sealed. It is useful when a patch has built up into a lump or a horn, and the scraped material can be sent for testing. It leaves a small scar, and like freezing it treats only the spot in front of you.
A small clear glass bowl holding a shallow pool of pale amber liquid on a white background, with a white fan-shaped brush lying beside it, bristles resting against the bowl.Diagram: how Chemical Peel works in the skin
Moderate evidence
A medium-depth peel takes off the damaged top layer across a whole face or scalp at once, so it treats the field rather than single spots. It is an option when creams have not been tolerated. The skin is red and peeling for about a week, and results depend a lot on who is doing it and at what strength.
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
Not a treatment, but the right answer for a patch that is thick, firm, tender, bleeding, growing quickly, bigger than about a centimeter, forming a horn, sitting on the lip or ear, or unchanged after proper treatment. A few minutes under local anesthetic tells you whether the abnormal cells are still confined to the top layer or have gone deeper. Freezing a patch like that instead removes the evidence without answering the question.

When to See a Dermatologist

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Rough, scaly patches are worth getting on the schedule for now rather than later, an early patch is quicker to treat, and appointments can be months out. Book if a rough patch keeps coming back in the same place, if you can feel a sandpapery area more easily than you can see it, or if several dry scaly spots on the face, scalp, ears, lips, hands or forearms have been there for months. Ask to be seen sooner if a patch is thickening, lumpy, tender, bleeding or crusting repeatedly, growing quickly, forming a hard horn, larger than about a centimeter, or unchanged after treatment - and have lip scaling that lip balm does not fix looked at, because the lip is higher-risk. Most are diagnosed by looking and touching, with a dermatoscope; a biopsy is used when a patch is thick, painful, bleeding, growing or has not cleared.

— Dr. Schwarz, Board Certified Dermatologist

Complications

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Squamous Cell Carcinoma

The skin cancer that these patches can turn into. Any one patch is unlikely to progress in any one year, but most squamous cell carcinomas begin in an actinic keratosis or in the damaged skin around one, and people usually have many patches over many years. Treating patches lowers how many of these appear later. A patch that thickens, hurts, itches, bleeds or grows quickly is sampled rather than frozen.

Actinic cheilitis on the lip

The same sun damage on the lower lip, where it shows up as persistent dryness, scaling, cracking or a lip border that has blurred into the skin. It is easy to read as chapped lips, and lip balm does not fix it. The lip matters more than its appearance suggests, because it is a higher-risk site if a patch progresses, so a dry scaly lower lip that has not settled in a month should be looked at.

Lookalikes

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Seborrheic Keratosis

Both are rough patches on sun-exposed skin in older adults, and people often have both at once. A seborrheic keratosis is thicker and looks stuck on, like a blob of wax sitting on the surface, usually tan to dark brown with a slightly greasy, warty texture. An actinic keratosis is flatter, pinker, gritty like sandpaper rather than waxy, and it comes and goes in the same spot. Seborrheic keratoses are harmless and are not precancers.

Basal Cell Carcinoma

A superficial basal cell carcinoma is a thin pink scaly patch, and on the face or trunk it can look very like an actinic keratosis. The differences are that it slowly gets bigger instead of coming and going, it often has a fine pearly or slightly raised edge, and it may crust, bleed and heal over and over in the same place. This is one of the main reasons a patch that does not clear after proper treatment gets a biopsy.

Warts

A wart on the back of a hand is rough and scaly too, which is why the two get mixed up. A wart is a firm dome that stands up from the skin with a cauliflower-like surface and often tiny black dots in it, it can appear at any age, and there may be several that spread to nearby fingers. An actinic keratosis is flat or only slightly raised, sits on skin that shows other sun damage, and appears in older adults.

Myths

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  • "It is just dry skin." Dry skin improves with moisturizer and moves around. An actinic keratosis returns in exactly the same place and feels gritty rather than flaky.
  • "It went away, so it is gone." Patches routinely flake off and return weeks later. Disappearing is how they behave, not evidence the damaged cells have cleared.
  • "It is a precancer, so there is no hurry." Any single patch is low risk in a given year. But people have many of them, over many years. Delay is not dangerous over weeks. It matters over years.
  • "Freezing them is cosmetic." Freezing destroys the abnormal cells in the patch, and treating them reduces how many squamous cell carcinomas develop later. That is medical, not cosmetic.
  • "The reaction to the cream means I am allergic." Redness, soreness, crusting and weeping is the expected response to fluorouracil and imiquimod. Genuine allergy is uncommon. Ask before stopping - stopping early undertreats the area.
  • "Only my face matters." The scalp, ears, lower lip, backs of the hands and forearms are all common sites, and the lip and ear carry higher risk.
  • "I have plenty of them, so treating a few is pointless." The opposite follows. Widespread patches are the case for treating the whole area, not for giving up on it.
  • "I got these from sunbathing in my twenties, so the damage is done." Past exposure cannot be undone, but ongoing exposure keeps adding to it. Sun protection now measurably reduces how many new patches appear.

Questions Patients Ask

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Is an actinic keratosis cancer?

No. It is a precancer - abnormal cells in the top layer of skin that have not formed a tumor. A minority become squamous cell carcinoma, and they are treated because most squamous cell carcinomas begin this way.

What are the chances mine turns into cancer?

Low, for any single patch in any single year. Published estimates vary too widely to quote. What matters is cumulative: more patches, for longer, with more sun. A suppressed immune system raises it considerably.

Does freezing hurt, and what will it look like afterward?

It stings for a few seconds and aches afterward. It blisters or crusts within a day or two and heals over one to three weeks. A pale mark often remains where the skin regrows with less pigment - sometimes permanent, and more noticeable on deeper skin tones.

Why does the cream make my skin look so much worse?

That is how it works. Fluorouracil and imiquimod provoke a reaction exactly where abnormal cells are, so the area turns red, crusted and sore, often revealing more patches than you knew you had. It settles a couple of weeks after finishing. Stopping early leaves the area partly treated.

Will they come back?

New ones almost certainly will, because the sun damage remains. That is not treatment failure. Most people settle into periodic checks, occasional retreatment and daily sun protection - the protection is what reduces how many new ones appear.

Should I treat the spots or the whole area?

A few discrete patches, and freezing is efficient. Many patches, or a whole area of damaged skin, and a cream or photodynamic therapy lasts longer, because it reaches cells that have not surfaced yet. Downtime is part of the choice.

References

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