Crushed ice

Ice and cold temperatures can help to relieve inflammation. The cold also numbs the skin, which can provide rapid but temporary relief. To treat irritation produced by a mosquito bite, the American Academy of Dermatology (AAD) suggests using a cool, moist cloth or an ice pack. In a pinch, a bag of crushed ice will suffice.

Ice should not be applied directly to the skin since it might cause injury. Instead, place a barrier between your skin and the ice, such as a washcloth. Apply a cold compress for up to 5 or 10 minutes many times a day to reduce itching.