Keratosis pilaris is a common genetic skin condition which appears as rough, bumpy, sometimes red skin most often found on upper arms, thighs, and cheeks. These bumps are due to a buildup of keratin, a hard protective protein found in skin, hair, and nails. This built up keratin forms a plug which blocks the opening of hair follicles. When these plugs, or bumps, become irritated it causes redness.
Keratosis pilaris usually presents in childhood, often at its worst during puberty, but can continue into adulthood. The condition usually improves in warmer weather, while dry weather seems to exacerbate symptoms.
There is no known cure for Keratosis pilaris, though steps can be taken to keep minimize bumps and redness.