Itchy red bags on the body may be caused by insect bite dermatitis, urticaria, eczema and so on. 1. Insect bite dermatitis: insect bite dermatitis may be caused by mosquitoes, bedbugs, fleas and other insect bites, the patient will appear windswept papules, papules, ecchymosis, blisters, the serious ones are accompanied by headache, joint pain, fever, itching and other manifestations. If the patient appears insect bite dermatitis, there will be long red bags on the body is very itchy symptoms. 2. Urticaria: the cause of urticaria is not clear, and is considered to be related to infection, drug factors, physical stimulation, mental factors. Patients will have symptoms such as windburn, angioedema, itching, panic, abdominal pain, diarrhea, vomiting and so on. Therefore, patients with urticaria, also manifested as itchy red bags on the body. 3. Eczema: the etiology of eczema is still unclear, may be related to internal infection, immune abnormalities, neuropsychiatric factors, blood circulation disorders, contact with animal fur. Patients will have symmetrical papules, papules, blisters, itching and other manifestations. If the patient suffers from eczema, there will be symptoms of itchy red bumps on the body. It is recommended that patients with itchy red bumps need to consult a doctor in time, the doctor will choose the appropriate method of treatment for the patient’s condition.