Keratosis pilaris (KP, also follicular keratosis), more commonly known as chicken skin, is a common, autosomal dominant, genetic follicular condition that is manifested by the appearance of rough bumps on the skin. It most often appears on the back and outer sides of the upper arms (though the lower arms can also be affected), and can also occur on the thighs, hands, and tops of legs, flanks, buttocks, or any body part except glabrous skin (like the palms or soles of feet).
Less commonly, lesions appear on the face, which may be mistaken for acne. Keratosis pilaris is completely harmless; however the condition can contribute to or exacerbate depression and anxiety.