Keratosis pilaris is a common skin condition in which a protein in the skin called keratin forms hard plugs within hair follicles.
Causes, incidence, and risk factors
Keratosis pilaris is harmless (benign), does not get worse over time, and often disappears with age. It is more common in patients who have very dry skin, or who have atopic dermatitis (eczema). It seems to run in families.
In mild cases, small bumps, similar in appearance to "goose bumps," are found on the backs of the upper arms. The texture is that of very coarse sandpaper.
Bumps may also appear on the buttocks and thighs. Less commonly, bumps appear on the face and may be mistaken for acne.
Individual bumps are small, skin-colored papules that form within hair openings (follicles). The condition is generally worse in winter and often clears in the summer.
- Fine, bumpy texture to skin over the outer upper arm and thigh or elsewhere
- Skin-colored bumps the size of a grain of sand
- Slight pinkness may be seen around some bumps
Signs and tests
Physical examination is usually all that is needed for your health care provider to make this diagnosis. Testing is usually not necessary.
Moisturizing lotions are often soothing and may help the appearance of the skin. Skin creams with medications containing urea, lactic acid, glycolic acid, salicylic acid, tretinoin, or vitamin D may be recommended by your physician. However, improvement often takes months and the bumps are likely to come back.
Keratosis pilaris may fade slowly with age.
Calling your health care provider
Call for an appointment with your health care provider (or discuss the condition during a routine visit) if you suspect that you have keratosis pilaris and the condition does not respond to use of over-the-counter moisturizing lotions.
Reviewed By: Michael Lehrer, MD, Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network; Linda Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.