Keratosis Pilaris

What causes keratosis pilaris

Keratin is a tough protein that protects the skin. In keratosis pilaris, extra keratin builds up and forms a hard plug that blocks the opening of a hair follicle. Many plugs together create a bumpy texture. A coiled hair may be trapped beneath some plugs, and the surrounding skin can become red or darker from mild inflammation.

The exact reason is not known, but it is linked to:

• genetics: it often runs in families and may be inherited in a dominant pattern
• dry skin, especially in winter and low humidity
• atopic dermatitis, asthma and hay fever
• ichthyosis vulgaris
• hormonal changes: often worse during puberty and pregnancy
• obesity
• some medicines, such as certain targeted cancer drugs

Symptoms

• tiny, rough bumps that feel like sandpaper or goosebumps
• skin-colored, white, red or brownish bumps; on darker skin they may look darker than surrounding skin
• most commonly on the outer upper arms, thighs, buttocks and cheeks
• usually painless; may itch slightly
• worse in cold, dry months and better in summer

Variants

• Keratosis pilaris rubra: more pronounced redness
• Keratosis pilaris atrophicans: rare forms that cause scarring and hair loss, for example of the eyebrows (ulerythema ophryogenes)

Keratosis pilaris vs similar conditions

Diagnosis

A doctor or dermatologist recognizes keratosis pilaris by its appearance and location. Tests are rarely needed.

Treatment

There is no cure, and treatment is optional since KP is harmless. Treatments control it while used; stopping usually lets bumps return.

Gentle skin care

• Use lukewarm, short showers and a soap-free, fragrance-free cleanser.
• Pat skin dry rather than rubbing.
• Moisturize within a few minutes of bathing.
• Use a humidifier in dry weather.
• Avoid harsh scrubbing or picking, which can cause redness, scarring and dark marks.

Exfoliating moisturizers

The most effective first-line treatments soften and remove keratin plugs:

• urea creams (10% to 40%)
• lactic acid or ammonium lactate lotions
• salicylic acid lotions or washes
• glycolic acid products

Apply once or twice daily. They may sting on irritated skin; start a few times a week. Improvement usually takes 4 to 12 weeks.

Prescription options

• topical retinoids (tretinoin, adapalene, tazarotene) to normalize skin cell turnover; avoid in pregnancy
• short courses of mild steroid creams for red, itchy flares
• laser and light treatments (such as pulsed dye laser) to reduce redness; some lasers can reduce bumps and darker marks

Outlook

Keratosis pilaris is not contagious and does not cause health problems. It is most noticeable in childhood and adolescence and often improves or disappears by the late twenties or thirties, though some adults keep it for life.

Frequently asked questions

What causes keratosis pilaris?

It is caused by a build-up of keratin that plugs hair follicles. It tends to run in families and is more common in people with dry skin, eczema, asthma or hay fever. Cold, dry weather makes it worse.

How do you get rid of keratosis pilaris?

You cannot cure it, but daily use of moisturizers containing urea, lactic acid or salicylic acid smooths the bumps within a few weeks. Gentle cleansing and avoiding scrubbing help. A dermatologist can prescribe retinoids or laser treatment for persistent bumps or redness.

Is keratosis pilaris contagious?

No. Keratosis pilaris is a common, harmless skin pattern. It cannot be passed from person to person.

Does keratosis pilaris go away with age?

Often, yes. It is most noticeable during childhood and the teenage years and frequently improves or fades by the late twenties or thirties. Some people have it throughout life.

Should I scrub or pick keratosis pilaris bumps?

No. Harsh scrubbing and picking can irritate the skin, cause redness and dark marks, and even scarring. Chemical exfoliants such as urea, lactic acid or salicylic acid work better and more gently.