Keratosis pilaris (ker-uh-TOE-sis pih-LAIR-is) is a common, harmless skin condition that causes dry, rough patches and tiny bumps, usually on the upper arms, thighs, cheeks or buttocks. The bumps generally don't hurt or itch.
Keratosis pilaris is often considered a variant of normal skin. It can't be cured or prevented. But you can treat it with moisturizers and prescription creams to help improve the appearance of the skin. The condition usually disappears by age 30.