Actinic keratosis, also called solar keratosis, is a skin growth that develops in sun-exposed skin, especially on the face, hands, forearms, and neck. It occurs most often in pale-skinned, fair-haired, light-eyed people beginning at age 30 or 40.

Actinic keratoses are persistent, noticeable, small red, brown, or skin-coloured patches that may become scaly, scabbed, or crusted. The patches may itch, burn, or sting.

Actinic keratosis may become skin cancer, but this isn't common. Actinic keratoses may be treated with cryotherapy (freezing), electrosurgery (burning), curettage (scraping), photodynamic therapy (a treatment combining light and medicine), or medicines that are put on the skin.