Red pimples and itchy, many are symptoms of papular urticaria, acute eczema or scabies, you need to go to the hospital dermatology department to make a clear diagnosis and then follow the doctor’s instructions to use medication. 1. Pemphigus urticaria, also known as insect bite dermatitis, is a localized inflammatory reaction caused by insect bites on the skin, mostly on the lower extremities, occurring at night in the spring and summer seasons. The manifestation of scattered red bumps on the body, bumps were round or fusiform, itching obvious. 2. Acute eczema is caused by the interaction of various reasons such as low immune function, endocrine disorders and external allergen stimulation. The main manifestation is the symmetrical appearance of scattered erythema, papules, vesicles and oozing, itching is intense. 3. Scabies is caused by scabies infection of the skin, through skin contact infection, has a strong contagious, often in kindergartens, dormitories and other places of aggregation of episodes. Scabies occurs in finger cracks, armpits, external genitals and other places with thin and tender skin, manifested as scattered red bumps and blisters on the skin, male external genital pimples are larger in size of pea grains, itching is obvious, and itching is aggravated at night. There may be other causes of red pimples itchy, it is recommended to go to the hospital in time to find out the cause, symptomatic treatment.