Insect bite reactions are due to hypersensitivity response of the body to the insect bites. The area of the bites gets progressively redder,inflamed and itchy and the inflammation response can be very intense and severe at times, even leading to the development of blisters.
Bed bug, sandflies and fleas are some common causes of insect bite reactions but it is often difficult to tell the exact insect that caused the bite from looking at the skin lesions.
Insect bite reactions often require the use of topical steroid creams to settle the inflammation. In severe cases, short courses of steroids may needed. Untreated, the bumps can persist for weeks to months.