what is an itch?
Itch (Latin: pruritus) is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to classify it as any one type of sensory experience. Pruritus ani (also known as anusitis), irritation of skin at the exit of the rectum (anus), causing the desire to scratch. 2  Referred itch, phenomenon in which a stimulus applied in one region of the body is felt as an itch or irritation in a different part of the body.