Actinic Keratosis: Symptoms, Causes, Treatment

Actinic keratosis (AK), also known as solar keratosis, is a common precancerous skin condition caused by long-term exposure to ultraviolet (UV) radiation from the sun or tanning beds.

It consists of rough, scaly patches or spots on sun-damaged skin and represents the most common precancerous skin lesion. While not cancer itself, some AKs can progress to squamous cell carcinoma (SCC), a type of skin cancer, if left untreated.

Symptoms and Appearance
AKs typically appear on sun-exposed areas such as:

Face
Scalp (especially bald areas)
Ears
Neck
Backs of hands
Forearms
Lips (actinic cheilitis)

Common characteristics:

Rough, dry, scaly, or crusty patches, often feeling like sandpaper.
Flat or slightly raised, usually under 1 inch (2.5 cm) in diameter.
Colors: pink, red, brown, tan, white, or gray; sometimes skin-colored.
May itch, burn, sting, bleed, or become tender.
Can develop a hard, wart-like or horn-like surface.
Often more easily felt than seen; they may come and go.

Causes and Risk Factors
AK results from cumulative UV damage that alters skin cell DNA (particularly keratinocytes). Key risk factors include:

Fair skin, light hair/eyes, tendency to freckle or burn easily.
Older age (more common after 40).
History of frequent sun exposure, sunburns, or indoor tanning.
Living in sunny climates or outdoor occupations/recreation.
Weakened immune system (e.g., from medications or conditions).

Diagnosis
A dermatologist usually diagnoses AK through visual examination. A skin biopsy may confirm it or rule out skin cancer if the lesion looks suspicious.

Treatment Options
Many AKs are treated to prevent progression to cancer and for cosmetic/comfort reasons. Options include:

Cryotherapy (freezing with liquid nitrogen) — Quick for isolated lesions.
Topical medications (e.g., 5-fluorouracil, imiquimod, diclofenac, or tirbanibulin) — Applied at home for multiple lesions; they treat visible and subclinical damage.
Photodynamic therapy (PDT) — Uses a light-activated cream.
Curettage or surgical removal — For thicker lesions.
Laser therapy or chemical peels — In some cases.

Some small AKs may resolve on their own with sun protection, but monitoring is essential.

Prevention

Daily broad-spectrum sunscreen (SPF 30+) and reapply often.
Wear protective clothing, wide-brimmed hats, and UV-blocking sunglasses.
Seek shade, especially 10 a.m.–4 p.m.
Avoid tanning beds.
Regular skin self-exams and professional dermatology check-ups (especially if you have a history of AK or skin cancer).

Important note: This is general information based on medical sources. AKs require professional evaluation—see a professional for personalized diagnosis and treatment, especially if you notice new or changing skin lesions. Early intervention is highly effective at preventing complications.