In 1660, Samuel Haffenreffer defined pruritus or itching as an unpleasant cutaneous sensation that elicits the desire to scratch.
This itching is called "primary" because it is not linked to any disorder that triggers itching of the scalp. It also requires adapted, specific treatment.
Itching (or pruritus) is one of the most common symptoms of sensitive scalp. It is reported by more than 38% of people in France who claim to have a sensitive scalp.
The scalp is highly innervated: there are approximately 600 nerve endings per cm² of skin. These nerve endings are found in the skin (the dermis and the epidermis) and are activated by stimuli such as heat, cold, mechanical pressure, etc. These stimuli are perceived as external aggression by a person suffering from sensitive scalp. The message produced and sent to the central nervous system is transcribed in the brain in the form of sensory perception. Itching, tightness, tingling and burning are all sensations that trigger the urge to scratch the scalp.