Itchy back can be caused by physiological factors (e.g. long time without bathing resulting in clogged pores), or by diseases such as prickly heat or eczema. 1. Physiological factors: If you don’t take a bath for a long time, or if your back is dusty, your pores may be clogged, which may lead to itchy back, so you don’t need to worry too much about it, and you can just clean it in time. 2. Prickly heat: It occurs in hot summer, due to sweat discharge obstacles, often appear small pimples, blisters, itching and other symptoms. Therefore, itchy back may be caused by prickly heat. 3. Eczema: Eczema is an inflammation of the superficial dermis and epidermis caused by a variety of factors, and its common symptoms are erythema, pimples and itching. The common symptoms are erythema, pimples and itching. Therefore, if your back is itchy, you can consider eczema. There are many factors that can cause itchy back, after excluding physiological factors, you should consult a doctor to clarify the cause, and treat the cause under the doctor’s reasonable guidance, in order to prevent the impact on the body.