As the mosquito is feeding, it injects saliva into your skin. Your body reacts to the saliva resulting in a bump and itching. Some people have only a mild reaction to a bite or bites. Other people react more strongly, and a large area of swelling, soreness, and redness can occur.

How long do mosquito bites itch?

Most mosquito bites itch for 3 or 4 days. Any pinkness or redness lasts 3 or 4 days. The swelling may last 7 days. Bites of the upper face can cause severe swelling around the eye.

Do mosquito bites itch if you don't scratch them?

Scratching mosquito bites may make the itching worse. Mosquito bites itch due to inflammation. Rather than relieving the itching, scratching an already inflamed area increases inflammation.