Whenever you sweat, your back itches like pins and needles. Consider prickly heat, summer dermatitis, cholinergic urticaria, and so on, and choose the appropriate medication according to the specific cause of the disease. 1. prickly heat: prickly heat and small adenohypophyseal duct blockage related, common in summer and hot and humid environment, can be used locally glycerine lotion, ichthyol glycerine lotion, itching severe can be oral phenylephrine, iproniazid. 2. Summer dermatitis: summer dermatitis and hot weather related, is the skin after sweating, sweat metabolites and dust in the skin surface retention stimulation caused by the local use of glycerine lotion, if there is a lesion you can choose a boric acid solution, wet compresses, the symptoms of the more serious people are recommended to choose hydrocortisone butyrate cream, mometasone furoate cream. 3. cholinergic urticaria: this is the skin local center body temperature rise caused by the appearance of small, very itchy dots, you can choose to ventilate the place, the symptoms are more serious can be taken orally ibastine, levocetirizine. A sweaty back like pins and needles like itch should be timely consultation, such as the need for medication should be used under the guidance of a doctor, can not blindly use their own.