Mosquito and other insect bites can be itchy and very annoying but there are simple methods that can be used to relieve the itching. Good ways to relieve an itchy mosquito bite include rubbing a wet bar of soap over the area or placing an ice cube or very cold water over the area. Taking a cold shower can help by reducing the swelling of the welts that can be caused by mosquito bites and it helps to reduce swelling by the constricting the capillaries near the surface of the skin and causing fewer antigens and antibodies to cause a reaction. You can also use common household items to relieve the itch, such as nail polish, toothpaste, mouthwash, vinegar, honey, underarm deodorant, rubbing alcohol, ammonia, bleach, or a hot tea bag placed on the area.