Keratosis pilaris is a common disorder in which dead cells shed from the upper layer of skin plug the openings of hair follicles.
The exact cause is not known, although heredity probably plays a role. Also, people with atopic dermatitis are more likely to have keratosis pilaris. However, keratosis pilaris does not seem to be a hypersensitivity or immune system disorder.
The bumps that occur in keratosis pilaris are small, skin-colored, or red and dry. They appear at hair follicles and make the skin feel rough. Sometimes they have plugs in the center that resemble small pimples. Generally, these bumps do not itch or hurt and cause only cosmetic problems. The upper arms, thighs, and buttocks are most commonly affected. The face may break out as well, particularly in children. The bumps are more likely to develop in cold weather and to clear up in the summer. The skin may appear red and may itch.
Treatment of keratosis pilaris is not needed unless the person is bothered by the appearance of the disorder. Skin moisturizers are the main treatment. Petrolatum ointment, creams with salicylic acid, lactic acid, urea, or tretinoin can also be used.
Doctors may use a pulsed dye laser (see Using Lasers to Treat Skin Problems) to treat facial redness if it is present and troublesome to the person.
Keratosis pilaris is likely to come back when treatment is stopped.