Actinic keratosis develops slowly. It most likely appears on areas of skin often exposed to the sun. These can include the face, ears, bald scalp, neck, backs of hands and forearms, and lips. It tends to lie flat against the skin of the head and neck, but appears as a bump on arms and hands. The base of an actinic keratosis may be light or dark, tan, pink, red, or a combination of these. Or it may be the same color as the skin. The scale or crust may be horny, dry, and rough. In some cases, it may itch or have a prickly or sore feeling.
Often, a person will have more than one actinic keratosis lesion. Actinic keratoses that develop on the lip are called actinic cheilitis.