Keratosis Pilaris

We are frequently asked to assess rashes for an allergic cause.

Keratosis pilaris (KP) is a particularly common rash. KP is a skin condition that causes small, rough bumps on the skin. It is most common in children and young adults.

It is not an allergic condition but has a strong genetic component. Keratosis pilaris (KP) is common and may be present in up to half the population. It is a completely harmless skin condition.

Its name gives some idea of what it is; ‘keratosis’ means that there is too much keratin, which makes up the tough horny outer layer of the skin, while ‘pilaris’ comes from the Latin for hair (pilus). In keratosis pilaris, many small (1 to 2 mm across) horny plugs can be seen blocking the hair follicles on the upper and outer parts of the arms and back of the thighs and also on the cheeks, especially in front of the ears.

The rash can look like goose bumps (sometimes called ‘chicken skin’) and feels slightly rough, like mild sandpaper. The bumps are usually flesh-colored or pink, they are seldom itchy. Keratosis pilaris usually starts in childhood and becomes more evident during adolescence and adulthood. For reasons not fully understood the condition seems to be better in the summer than in the winter perhaps because in winter the skin often gets dry while in summer the sweat makes it less dry. The rash may ‘wax and wane’ in intensity, and the reasons for this relate to hormonal factors that influence keratin production in the skin.

Unlike eczema, KP will not increase the likelihood of developing food or aero allergies.

There is no cure for KP, but there are treatments that can help improve the appearance of the bumps. These treatments include:

• Moisturizing. Keeping the skin well-moisturized can help to soften the bumps and make them less noticeable.

• Exfoliating. A mild exfoliator can help remove dead skin cells and clear the pores.

• Topical medications. There are several topical medications with ‘keratolytic properties’ that can help to treat KP, such as salicylic acid, urea, and retinoids - in the first instance, you may wish to trial Ucerin (Ucerax) which is available over the counter.

Here are some additional tips for managing KP in children:

• Avoid harsh soaps and detergents. These can dry out the skin and make the bumps worse.

• Wear loose-fitting clothing. Tight-fitting clothing can rub against the skin and irritate the bumps.

• Keep the skin cool and dry. Hot, humid weather can make KP worse.

• KP is a chronic condition, and there is no quick fix.