Itchy red spots on the back may be caused by certain diseases, such as eczema, folliculitis, dermatitis, etc., and you should consult a doctor in time to find out the cause of the disease. 1. Eczema: it occurs in allergic people, caused by a variety of internal and external factors in the superficial dermis and epidermal inflammation, can be manifested as dense red papules, papules, can be accompanied by intense itching, drinking alcohol, soap, hot water, scratching symptoms can be aggravated, and in severe cases, it can affect the sleep. 2. Folliculitis: poor personal hygiene, sweating, unhygienic swimming pools and other triggers, easy to lead to bacteria, fungi and other pathogens caused by follicle infections, often manifested in the formation of red papules around the hair follicles, accompanied by red, swollen, hot, painful inflammatory reaction, can be accompanied by itching, pain and other discomforts, the serious cases can also be pus, ulceration and so on. 3. Dermatitis: red spots on the back can also be caused by various types of dermatitis, such as insect bite dermatitis, summer dermatitis, neurodermatitis, etc., which can cause red pimples, small blisters, and itching and other symptoms. In addition, red spots on the back can also be caused by hives and other diseases, but this symptom alone is not enough to diagnose the disease, you should go to the dermatology department of the hospital in a timely manner, to clarify the cause of the disease, and to carry out the appropriate treatment. At the same time need to try to avoid irritation, scratching, so as not to aggravate the condition.