Question: How does scratching relive an itch?

Maheen Siddiqui answered on 15 Jun 2016:

We know that there are receptors in the skin which can send signals to the brain.

Research in the recent years has actually shown that when you start scratching an itch, these receptors send messages to the brain and the brain then tries to block the itch by producing the hormone “serotonin”.

This is actually known as the happy hormone – its also actually said to be released when you eat chocolate (maybe thats why we all feel so happy having chocolate!). When this happy hormone is released, it blocks the itching sensation!

But this is only temporary relief, after a while the itching sensation may be replaced by pain because although the brain releases the happy hormone, it also tries to block the itch by producing pain. So in some cases, scratching may make the itch worse!