The cause of red pimples with itching may be triggered by folliculitis, scabies, papular urticaria and other causes. 1. Folliculitis: Folliculitis is an inflammatory skin disease mainly involving hair follicles, caused by bacterial or fungal infections, the main manifestation is a red pimple or pustule centered on the hair follicle, and will be accompanied by itching and pain. 2. Scabies: considered to be a contagious disease caused by human scabies mite parasites in the skin, this phenomenon is more often occurs in the thin and tender skin, such as finger cracks, external genitals and underarms and other parts. Common symptoms will show erythema, papules and itching. 3. Pemphigus urticaria: Pemphigus urticaria is an allergic skin disease that occurs after insect bites, there will be a cluster or scattered pimples like wind, and there will be intense itching. The causes of the disease are different, the specific treatment will be different, it is not recommended to treat privately, it is recommended to go to the hospital in time.