Skinformation A - Z Skinformation Keratosis pilaris What is keratosis pilaris? Keratosis pilaris (KP) is a very common and may be present in half the population. It is a completely harmless skin condition. It affects 50-70% of adolescents and approximately 40% of adults. 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 thighs. This can look like goose bumps but feels slightly rough. Keratosis pilaris appears when extra keratin accumulates in the hair follicles. This usually starts in childhood and becomes more obvious during adolescence and in 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. Keratosis pilaris may be associated with ichthyosis vulgaris and atopic eczema, however this may be coincidental. What causes keratosis pilaris? Causes of keratosis pilaris are not fully understood but it is genetic in more than half those affected with it. Keratosis pilaris is harmless and is not infectious but can cause emotional discomfort. Is keratosis pilaris hereditary? It is usually found in more than one member of a family. The way it is inherited varies from family to family, but it often fits into an ‘autosomal dominant’ pattern; this means that there will be a 1 in 2 chance that each child of an affected parent will inherit the condition. What are the symptoms of keratosis pilaris? Some people find their keratosis pilaris looks unattractive. The skin feels rough, dry and appears as though it has permanent goose bumps. Occasionally keratosis pilaris is itchy. What does keratosis pilaris look like? The groups of small bumps are most common on the backs of the upper arms and on the fronts of the thighs. Sometimes keratosis pilaris also affects the buttocks and lower back and chest and, in less common forms, the face and eyebrows as well. Some redness may appear around the small bumps. How will keratosis pilaris be diagnosed?There are no specific tests for keratosis pilaris; however, your doctor will recognise it easily. A biopsy is seldom needed and would be requested by your dermatologist, especially if it is associated with acne or eczema that do not get better with treatment. There are other conditions that look similar to KP and the biopsy will confirm diagnosis. Can keratosis pilaris be cured? No; however, it often (but not always) does clear up during adult life. How can keratosis pilaris be treated? No treatment clears keratosis pilaris completely, but it can improve the condition temporarily. Emollients (moisturisers) can be of benefit. Creams containing salicylic acid, lactic acid and/or urea are more effective than emollients and can be purchased over the counter or obtained on prescription from the doctor. Other treatments can be used but they are not offered on the NHS and can be expensive, and none of them cures it. These include corticosteroids topically, photodynamic therapy, various lasers, chemical peels and dermabrasion. In many cases it may be best to wait for the problem to improve on its own. CAUTION: This leaflet mentions ‘emollients’ (moisturisers). When paraffin-containing emollient products get in contact with dressings, clothing, bed linen or hair, there is a danger that a naked flame or cigarette smoking could cause these to catch fire. To reduce the fire risk, patients using paraffin-containing skincare or haircare products are advised to avoid naked flames completely, including smoking cigarettes and being near people who are smoking or using naked flames. It is also advisable to wash clothing and bed linen regularly, preferably daily. Self Care (What can I do?) General measures to reduce skin dryness may help: Use mild soaps Soap substitutes Apply emollients (moisturisers) frequently Have tepid showers or baths rather than hot showers or baths The gentle use of an exfoliator may sometimes be of help This information is provided by the British Association of Dermatologists.Need to talk? Find out more about our forum and 'Ask the Expert' sessions. Donate to skin disease research.