What Is Peripheral Sensitisation?

A Local Chemical Response to Injury

Following tissue injury, a cocktail of inflammatory mediators — including prostaglandins, bradykinin, histamine and nerve growth factor — is released into the surrounding tissue, directly acting on the peripheral nerve endings (nociceptors) in that area.

Lowering the Threshold to Fire

This inflammatory "soup" lowers the threshold at which local nociceptors fire and increases their responsiveness to subsequent stimulation — a process termed peripheral sensitisation (Gold & Gebhart, 2010). The practical effect is that stimuli which would normally be non-painful (light touch, gentle movement) can become painful in the injured area, and genuinely painful stimuli feel more intense than they otherwise would.

A Protective, Adaptive Response — Usually

This heightened local sensitivity is generally a useful, adaptive short-term response that encourages protection and rest of the injured area while healing takes place, and typically resolves as the underlying inflammation settles. It becomes clinically problematic mainly when it persists well beyond the expected tissue healing timeframe, or when it contributes to the development of more widespread central sensitisation.