Keratosis pilaris is a very common harmless skin condition appearing as small, whitish bumps on the upper arms and thighs, especially of children and young adults. Individual lesions of keratosis pilaris begin when a hair follicle becomes plugged with keratin, a protein found in skin, hair, and nails.
Who’s At Risk
Keratosis pilaris can affect people of any age, any race, and either sex. It is more common in females.
Keratosis pilaris usually starts in early childhood (by age 10) and can worsen during puberty. However, it frequently improves or even goes away by early adulthood.
Keratosis pilaris can affect 50-80% of teenagers and up to 40% of adults. Many people have a family history of keratosis pilaris. A large number of individuals with ichthyosis vulgaris (an inherited skin condition characterized by very dry, very scaly skin) also report having keratosis pilaris.
Signs & Symptoms
The most common locations for keratosis pilaris include the following:
- Backs of the upper arms
- Fronts and sides of the thighs
Tiny (1-2 mm) white to gray bumps occur, centered in the hair follicle. Sometimes, a thin, red ring may surround the white bump, indicating inflammation. The bumps all look very similar to one another, and they are evenly spaced on the skin surface.
Rarely, people with keratosis pilaris may complain of mild itching.
Keratosis pilaris tends to improve in warmer, more humid weather, and it may worsen in colder, drier weather.
There is no cure for keratosis pilaris, though its appearance can be improved. It is often helpful to keep the skin moist (hydrated) and to use mild, fragrance-free cleansers, with daily applications of moisturizer.
Creams and ointments are better moisturizers than lotions, and they work best when applied just after bathing, while the skin is still moist. The following over-the-counter products may be helpful:
- Preparations containing alpha-hydroxy acids such as glycolic acid or lactic acid
- Creams containing urea
- Over-the-counter cortisone cream (if the areas are itchy) such as 1% hydrocortisone cream
Do not try to scrub the bumps away with a pumice stone or similar harsh material; these approaches may irritate the skin and worsen the condition.
Similarly, try to discourage your child from scratching or picking at the bumps, as these actions can lead to bacterial infections or scarring.
When to Seek Medical Care
Keratosis pilaris is not a serious medical condition and has no health implications. However, if self-care measures are not improving the appearance of the skin and it continues to bother your child there are some prescription options for treatment that could be considered.
Prescription Treatment Options
Treatments are aimed at controlling the rough bumps, not curing them. Keratosis pilaris bumps will come back if therapy is stopped.
Prescription treatments for keratosis pilaris sometimes include:
- Prescription-strength alpha- or beta-hydroxy acids (glycolic acid, lactic acid, salicylic acid)
- Prescription-strength urea
- A retinoid such as tretinoin or tazarotene
- High concentrations of propylene glycol
- If the skin is itchy or inflamed, the short-term prescription strength topical corticosteroid to reduce the inflammation may be considered
Usually, consistent home use of over-the counter creams is enough to manage the symptoms of keratosis pilaris.
- Feature image of KP on arm downloaded from https://dermnetnz.org/topics/keratosis-pilaris-images on 18 August 2022