What is chicken skin? ”Chicken skin” is the scientific name for peri-herpetic keratosis, commonly found on the skin of the back and extremities, especially on the outer skin of the upper arms and thighs, with many small bumps and papules, in each small papule there is a curly sweat hair, the tip of the papule has a light brown keratin plugs, after peeling off the keratin plugs, leaving a funnel-like depression, the skin is like chicken skin, hence the name “chicken skin”. How does chicken skin arise? Keratosis pilaris is a chronic keratotic skin disease of the hair follicle, the cause of which is still unclear. Due to keratinization of the hair follicle opening, the follicle opening is blocked by overly thick keratin, which affects the growth of fine hairs and forms a small papule. The light brown keratin at the top of the papule is formed by the aggregation of epithelial cells from the concentrated keratinized hair follicles.