Actinic keratoses

About actinic keratoses

Actinic keratoses are common lesions that develop on your skin as a result of cumulative life-long exposure to the sun. The lesions develop when your skin can’t repair the damage that has been caused by ultraviolet (UV) light. In the UK, about one in four people over 60 have actinic keratoses.

Symptoms of actinic keratoses

At first, you may notice small, rough spots on areas of your skin that are frequently exposed to sunlight, such as the skin on your face, ears, forearms and hands. These lesions can, however, develop anywhere on your body that is repeatedly exposed to the sun. The spots usually have no other symptoms but feel rough and are sometimes like sandpaper. They may also come and go without treatment.

Most actinic keratoses are about 5 to 10mm wide. Over time, the spots may get bigger (up to about 20mm) and usually become red and scaly. However, their appearance can differ hugely. For example, they may be skin coloured, pink or brown. Also, they can become raised, hardened and wart-like and may even develop a small horn-like growth. Equally, they can remain soft or flat. The skin surrounding the actinic keratoses often looks sun-damaged, for example, blotchy and wrinkled.

If you have any of these symptoms, see your GP.

Complications of actinic keratoses

Actinic keratoses are usually harmless but show that the skin cells have been significantly damaged (dysplasia). If the damage progresses, the cells can develop into a type of skin cancer called squamous cell carcinoma, but this is rare, happening to less than six in 100 people with actinic keratoses. If your actinic keratoses lesions become tender or form a nodule with crusting on your skin, see your GP as this can be an early sign of skin cancer.

Treatment can be effective if the cancerous changes in your skin are diagnosed early. See our skin cancer factsheet for more information.

Causes of actinic keratoses

Actinic keratoses are caused by repeated exposure to UV radiation from the sun. The more time you have spent in the sun throughout your life, the more likely you are to develop the condition. Because of this, people living in sunny countries, such as Australia, have a higher risk of developing actinic keratoses.

You may also be more at risk of developing actinic keratoses if you:

  • are fair skinned, with blue eyes and blonde or red hair
  • tend to burn rather than tan
  • use sunbeds
  • have a weakened immune system – for example, if you have HIV/AIDS, or take medicines that suppress your immune system

There are also certain genetic conditions, such as xeroderma pigmentosum (where your skin is unusually sensitive to the sun) or albinism (where you have no pigment in your skin, hair and eyes), which will also increase your risk of developing actinic keratoses. However, these types of conditions are very rare.

Diagnosis of actinic keratoses

Your GP will ask about your symptoms and examine your skin. The appearance and distribution of the actinic keratoses on your body is usually enough to confirm a diagnosis.

If your lesions become tender, grow or bleed, you may be referred to a dermatologist (a doctor who specialises in identifying and treating skin conditions). He or she may take a sample of your skin (known as a biopsy) under a local anaesthetic, to check for skin cancer. This will be sent to a laboratory for testing.

Treatment of actinic keratoses

Depending on the severity of your condition, your GP will be able to advise you about which treatment is most suitable. Sometimes, actinic keratoses can disappear on their own without treatment. If you have been diagnosed with actinic keratoses, you should always take extra care in the sun (see Prevention).

Topical medicines

Your GP may prescribe one of the following topical medicines to treat actinic keratoses. A topical treatment is a medicine you apply directly to your skin.

  • Diclofenac gel. This can be effective in clearing mild actinic keratoses. You apply a thin layer of the gel twice a day for three months.
  • 5-fluorouracil cream. This can be used for most types of actinic keratoses (mild to severe). You apply a thin layer of the cream to the affected area, once or twice a day, for about four weeks. You should expect to develop a red reaction which is slightly uncomfortable after two to four weeks. Don’t apply this cream if you're pregnant or breastfeeding as it can cause harm to your baby.
  • Imiquimod cream. You rub the cream directly onto the affected area. The treatment is repeated three times a week for four weeks. You're likely to develop a red reaction which is slightly uncomfortable after two to four weeks. If the actinic keratoses hasn’t improved after treatment, you may need a further course.

These treatments can cause side-effects such as itching, redness and rashes. Always ask your GP for advice and read the patient information leaflet that comes with your medicine.


This involves freezing your actinic keratoses lesions with liquid nitrogen. Cryotherapy is less likely to leave a scar than surgery, but it can sometimes leave a pale mark. Cryotherapy can be quite uncomfortable, so it's usually used when there are only a few small actinic keratoses, or if you have the more scaly type of lesions that are known to respond less well to topical treatments.

Photodynamic therapy

This uses a cream to sensitise the actinic keratoses to light. Shining a light on the affected area will cause the sensitised skin cells to become inflamed and be replaced by healthy cells. Your doctor will prepare your skin by scraping off the crusted surface of your actinic keratoses lesions and applying a special cream, which contains a chemical that is only absorbed by sun-damaged cells. A special light is then shone on the area to activate the chemical and destroy the sun-damaged cells. If necessary, the treatment can be repeated. However, this treatment can be quite painful.


If you have thickened and horn-like actinic keratoses lesions, your GP or dermatologist may advise that they are surgically removed. This is done under a local anaesthetic and you will stay awake during the procedure. You may find the anaesthetic injections uncomfortable but pain from the areas will be completely blocked.

The actinic keratoses lesions can be scraped off with an instrument called a curette or may be cut out if your doctor suspects that skin cancer may have developed. All these procedures will leave a scar. Samples can be taken from the actinic keratoses to send to a laboratory for testing. This can confirm your diagnosis and determine whether there are any signs of skin cancer.

Prevention of actinic keratoses

Developing actinic keratoses is a sign that your skin is ageing and has been damaged by the sun. You can reduce your risk of developing actinic keratoses, or prevent your condition from becoming any worse, by following the advice below.

  • Stay out of the sun when the sun is at its strongest – this is between 11am and 3pm in the UK during the summer. Times can vary in different countries.
  • Use a sunscreen with an SPF (sun protection factor) of at least 25. Make sure that it protects you from UVA and UVB radiation. UVA protection may be shown with a star rating between zero and five, with five stars being the highest level of protection. Reapply it as per the manufacturers’ instructions.
  • Wear a broad-brimmed hat and long sleeves to protect the most sun-exposed areas of your skin.
  • Use sun glasses that have UV protection.
  • Never use a sunbed.

If you already have actinic keratoses, keep an eye on your skin every few months for any changes, such as a lesion getting larger or sore. If this happens, see your GP.

Can I catch actinic keratoses from other people?


No. Actinic keratoses are not infectious, so you can’t catch them from someone else or spread them to other people.


Actinic keratoses develop when your skin cells are damaged by long-term sun exposure. The patches of rough, scaly skin that are characteristic of the condition aren’t infectious, so you can’t catch them from another person. Equally, if you have actinic keratoses, you can’t spread them to anyone else.

Do actinic keratoses run in the family?


No. However, certain factors that make actinic keratoses more likely to develop can be inherited, such as having fair skin and fair hair, and burning easily.


You may be more likely to develop actinic keratoses if you have fair skin, or if you burn easily without getting a tan. This depends upon your skin type, which you inherit through genes from your parents. As the main factor for developing the condition is sun exposure, you should always use adequate sun protection measures. See Prevention for more information.

How likely is it that my actinic keratoses will become cancerous?


Most actinic keratoses will not become cancerous. The signs that actinic keratoses are turning into skin cancer are that the lesions will become tender, raised, more scaly, bleed and grow over time.


Sometimes actinic keratoses will disappear on their own and do not need treatment. However, they may stay the same or turn into a type of skin cancer known as squamous call carcinoma, although this is rare. This happens to less than six in 100 people who have actinic keratoses.

If you notice that the actinic keratoses become tender, lumpy, more scaly, or if they ulcerate or bleed, this may indicate a change into a cancer. See your GP or dermatologist (a doctor who specialises in identifying and treating skin conditions) if you see these types of changes.

Using sunscreen will help to reduce your chances of developing more actinic keratoses and may lower your risk of skin cancer.