What causes actinic keratosis?

Repeated sunlight can alter the way skin cells grow and mature. Over time, a small area may feel rough like fine sandpaper before it is easy to see. It may look pink, red, tan, or brown, and can occur on the face, ears, scalp, forearms, or backs of the hands. Outdoor exposure, reflected light, and past sunburns all add to cumulative ultraviolet injury.

An actinic keratosis is not the same as a harmless age spot. Some lesions remain localised, while others become thicker or more inflamed, so a clinician should identify an uncertain or changing patch.

Use broad-spectrum sunscreen on exposed skin, wear protective clothing and a brimmed hat, and seek shade during strong sunlight. Do not scrape, freeze, or apply strong acids to a rough patch without medical advice. A dermatologist may recommend monitoring, a prescribed cream, freezing, scraping, or a light-based procedure depending on the lesion and surrounding sun damage.

Arrange a skin examination for a rough patch that persists, returns, becomes tender, thickens, or appears on a highly sun-exposed site. Seek prompt review for bleeding, a sore that does not heal, rapid growth, or marked pain. These features do not establish a diagnosis, but they make timely assessment especially important.

Ask whether the patch is an actinic keratosis or another skin change, whether treatment or observation is appropriate, and how to protect nearby skin. Ask what changes should prompt an earlier appointment.