Itch

Itch
A man scratching his back
SpecialtyDermatology
SymptomsCompulsion to scratch an irritated area of skin
CausesCertain infections, allergies, blood derangements and environmental factors
Risk factorsDry skin
Diagnostic methodOften based on the causes of itching
Differential diagnosisPain
TreatmentAntipruritics, 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]

  1. ^ Andersen HH, Elberling J, Arendt-Nielsen L (September 2015). "Human surrogate models of histaminergic and non-histaminergic itch". Acta Dermato-Venereologica. 95 (7): 771–777. doi:10.2340/00015555-2146. PMID 26015312.
  2. ^ Ikoma A, Steinhoff M, Ständer S, et al. (July 2006). "The neurobiology of itch". Nature Reviews. Neuroscience. 7 (7): 535–547. doi:10.1038/nrn1950. PMID 16791143. S2CID 9373105.
  3. ^ Greaves MW, Khalifa N (October 2004). "Itch: more than skin deep". International Archives of Allergy and Immunology. 135 (2): 166–172. doi:10.1159/000080898. PMID 15375326. S2CID 13376216.