This page was reviewed under our medical and editorial policy by
Frederick L. Durden, Jr, MD, Plastic and Reconstructive Surgeon & Microsurgical Reconstructive Surgeon
This page was updated on October 20, 2022.
Actinic keratosis is a common precancerous condition that may put patients at risk for developing skin cancer.
Actinic keratosis (AK) is a skin lesion that often appears as a scaly patch of rough skin, a loss or change in skin color or another abnormal area. This condition is also referred to as a solar keratosis.
More than 40 million Americans a year develop this precancerous condition, according to the American Academy of Dermatology Association.
Actinic keratosis is typically caused by exposure to ultraviolet (UV rays) through sunlight or the use of tanning beds. These rays may damage skin cells called keratinocytes, resulting in AKs. For these reasons, AKs tend to occur on parts of the body that get the most sun, namely the:
Patients may notice one or more AKs, as they often appear in packs.
Knowing more may help people catch AKs early and have them treated.
About 0.025 percent to 16 percent of actinic keratosis diagnoses progress to cancer eventually. And approximately 10 percent of actinic keratoses turn into squamous cell carcinoma (a type of skin cancer) specifically.
Unprotected exposure to the sun’s damaging rays confers the greatest risk for developing AKs, but some factors add to that risk, including:
Not all AKs look the same. They may:
AKs don’t necessarily cause symptoms, but the patient may feel itching, stinging or pain in the area. In addition, AKs may bleed, and they may stick to clothing, which may hurt.
The patient's dermatologist may be able to tell if the growth is an AK by examining it. If skin cancer is suspected, a biopsy may be necessary.
Many treatments are used for AKs. Treatment decisions should be based on how many AKs the patient has, where they’re located, what they look like, and the patient's personal history of skin cancer.
Some are in-office treatments and others may be performed at home. Each AK treatment has its own set of pros and cons.
Cryosurgery: This procedure involves freezing the AK using a cold substance such as liquid nitrogen. The AK falls off after several days. The patient's skin may crust or blister at the treatment site. Sometimes more than one treatment is needed.
Chemical peels: Yes, the same chemical peels used to remove dead skin and reveal a brighter facial complexion may also get rid of AKs. These are strong peels that may only be done under a doctor’s supervision. They remove the layers of skin where the AKs reside. Keep in mind, the patient's skin may be red and swollen until it heals.
Curettage: If the patient's AKs are thick, the dermatologist may opt to scrape them off. This is called curettage. It may be paired with another procedure called electrodesiccation, which targets any remaining AK cells with heat.
Photodynamic therapy: If the patient continues to develop new AKs or they keep coming back, photodynamic therapy may be an option. First, the doctor applies a solution to the skin that makes it more sensitive to light. After about 60 to 90 minutes, the patient is exposed to a blue or red laser light, which activates the solution and destroys the AK. Some after-care instructions are recommended for the patient to follow, which include avoiding the outdoors during daylight hours. Exposure to any UV light may harm the treated area. More than one photodynamic therapy treatment is typically required for optimal results.
Laser resurfacing: In addition to removing damaged layers of skin to reveal a more youthful complexion, laser resurfacing may also help with lip AKs or actinic cheilitis. The laser energy removes the layers of skin where AKs reside. It may take up to two weeks to heal.
Many topical therapies may be used at home to destroy the outermost layer of the skin and any AKs. This list includes:
Fluorouracil (5-FU): This drug destroys AK cells on or near the skin’s surface and may be recommended to treat AKs on the chest, arms or back. It’s not typically recommended for AKs on the face because it may make the skin red and sensitive. The patient uses the medication once or twice a day for up to four weeks. Sun sensitivity may occur. 5-FU cream can’t be used if the patient is pregnant.
Imiquimod: One in a class of drugs known as immune response modifiers, imiquimod is applied once a day for up to two days a week. Treatment typically lasts 16 weeks even if the AKs are all gone before that time. Unlike Fluorouracil (5-FU), it may be used on the face, as it doesn’t cause as much redness. Potential side effects include redness, itching, burning, bleeding, flaking or dryness.
Diclofenac sodium: A topical nonsteroidal anti-inflammatory gel, diclofenac sodium is sometimes used to treat AKs. Exactly how it works isn’t fully understood. The gel is applied twice a day for two to three months. The patient may experience redness, itching, peeling or dry skin and/or muscle, joint or back pain.
All three of these drugs are U.S. Food and Drug Administration (FDA)-approved to treat AKs. Sometimes medications are paired with in-office procedures.
The best way to reduce the risk for developing AKs is to use a broad-spectrum sunscreen with a sun protection factor (SPF) of 30 or higher every day—and to reapply it frequently. It’s also important to practice other sun-safe behaviors, such as:
It's important to perform skin self-checks regularly, and if anything suspicious or different is discovered, check in with the dermatologist. It’s also important to schedule a yearly skin cancer exam. Catching and treating AKs early is an important step in helping to prevent skin cancer.