Keratosis pilaris is a common condition characterized by the formation of bumps and rough, dry patches of skin. It usually appears on the thighs, cheeks, buttocks or upper arms.

It occurs as a result of a buildup of keratin, the hard protein that protects the skin from infection and harmful substances. Keratosis pilaris is more common when other skin conditions are present, such as atopic dermatitis (eczema). 

The conditions may develop at any age, but it more common in young people and usually disappears by the age of 30. Symptoms of keratosis pilaris are small, painless bumps, dry and rough skin, and a worsening of the condition at certain times of the year, usually when there are lower humidity levels. 

Treatment of keratosis pilaris is usually not necessary and there is no cure, but the symptoms may be relieved by moisturizing, avoiding scratching, using a humidifier, and washing with warm water rather than hot. In some cases, a dermatologist may prescribe medication, for example, keratolytic agents and topical retinoids for use for acne.