triple response
Last reviewed 01/2018
The triple response is a simple way of demonstrating the early phases of acute inflammation. A patch of skin is mechanically 'injured' by lightly scratching with a nail; it produces the sequential triad:
- immediate local reddening due to vasodilatation secondary to the release of chemical inflammatory mediators, particularly histamine
- surrounding red flare response due to chemical mediators stimulating local free nerve endings
- weal response - local swelling - due to cytokines increasing local vascular permeability to give an exudate