During the wound-healing process, these nerves signal the spinal cord that skin is being stimulated. The brain perceives those signals as itchy. These nerves are also sensitive to chemicals, such as histamine, which the body releases in response to an injury.

Is it normal for a wound to itch?

Itchiness is a normal part of wound healing. To understand the cause of itching, you have to understand how a wound — even one closed with stitches — is rebuilt.

Why do itch get worse when you scratch?

First, scratching causes a sensation of pain. Then the body makes more serotonin to control the pain. As well as inhibiting pain, the serotonin activates the GRPR neurons via the 5HT1A receptors. The activated GRPR neurons then make the itching sensation worse.