Overview

Keratosis pilaris (ker-uh-TOE-sis pih-LAIR-is) is a common, harmless skin condition that causes dry, rough patches and tiny bumps, often on the upper arms, thighs, cheeks or buttocks. The bumps usually 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.

Symptoms

Keratosis pilaris can occur at any age, but it's more common in young children. Signs and symptoms include:

  • Painless tiny bumps, typically on the upper arms, thighs, cheeks or buttocks
  • Dry, rough skin in the areas with bumps
  • Worsening when seasonal changes cause low humidity and dry skin
  • Sandpaper-like bumps resembling goose flesh

When to see a doctor

Treatment for keratosis pilaris usually isn't necessary. But if you're concerned about your or your child's skin, consult your family doctor or a specialist in skin conditions (dermatologist).

Causes

Keratosis pilaris is caused by the buildup of keratin — a hard protein that protects skin from harmful substances and infection. The keratin blocks the opening of hair follicles, causing patches of rough, bumpy skin.

It's not clear why keratin builds up in people with keratosis pilaris. It may occur in association with a genetic disease or with skin conditions such as atopic dermatitis. Dry skin tends to make keratosis pilaris worse.

Jan. 16, 2021
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  2. Keratosis pilaris. American Osteopathic College of Dermatology. http://www.aocd.org/skin/dermatologic_diseases/keratosis_pilaris.html. Accessed Oct. 2, 2020.
  3. Keratosis pilaris. Merck Manual Professional Version. https://www.merckmanuals.com/professional/dermatologic-disorders/cornification-disorders/keratosis-pilaris. Accessed Oct. 2, 2020.
  4. Keratosis pilaris. American Academy of Dermatology. https://www.aad.org/public/diseases/a-z/keratosis-pilaris-overview. Accessed Oct. 2, 2020.
  5. Dermatologists' top 10 tips for relieving dry skin. American Academy of Dermatology. https://www.aad.org/dermatology-a-to-z/health-and-beauty/general-skin-care/dry-skin-tips. Accessed Oct. 2, 2020.