Itch | |
---|---|
A man scratching his back | |
Specialty | Dermatology |
Symptoms | Compulsion to scratch an irritated area of skin |
Causes | Certain infections, allergies, blood derangements and environmental factors |
Risk factors | Dry skin |
Diagnostic method | Often based on the causes of itching |
Differential diagnosis | Pain |
Treatment | Antipruritics, phototherapy |
An itch (also known as pruritus) is a sensation that causes a strong desire or reflex to scratch.[1] Itches have resisted many attempts to be classified as any one type of sensory experience. Itches have many similarities to pain, and while both are unpleasant sensory experiences, their behavioral response patterns are different. Pain creates a withdrawal reflex, whereas itches leads to a scratch reflex.[2]
Unmyelinated nerve fibers for itches and pain both originate in the skin. Information for them is conveyed centrally in two distinct systems that both use the same nerve bundle and spinothalamic tract.[3]