Goose bumps during bowel movements are considered to be caused by skin irritation. The pelvic nerves are in a state of alternating contraction and diastole during defecation, and the body’s heat will be reduced after something is discharged from the body during defecation, causing a feeling of coldness. Patients with sensitive nerves may experience localized skin nerve reactions, and some people may also experience this phenomenon when they urinate. You can use warm water for a sitz bath or hot compresses on the sphincter and perianal muscles after a bowel movement, which will help relieve the goose bumps. Therefore, goose bumps when defecating are a normal physiological reaction, do not worry too much, if necessary, you can apply hot compresses or sitz bath to relieve.