JUL 20, 2017

Why Do Mosquito Bites Itch?

WRITTEN BY: Xuan Pham

It's the height of summer, and that means mosquitoes are out in full force. If of these tiny terrors feasts on your blood even just a fraction of a second, you'll develop the unmistakable wheal complete with the unending itchiness. But what causes this reaction?

When a mosquito bites, it pierces the victim's skin with a proboscis - a tiny needle at its mouth that's used to draw out blood. In the process, the mosquito also releases some of its own proteins into the victim's skin. The proteins act to stop your blood from clotting around the bite, but it also triggers an immediate response from the immune system. The body responds by launching a flood of histamine, which causes the bite wound to swell up, and the local itching.

And try as you might, you'll most likely end up scratching the bite. Scratching triggers a temporary pain sensation, which can mask the feeling of itchiness. But beware, scratching worsens the itchiness because while serotonin, the neurotransmitter that gets released when you scratch, can promote pain relief, it can also induce itching. The best remedy? Apply some topical corticosteroids to help the histamine reaction calm down.