There are many possible causes of arm acne, such as keratosis pilaris, urticaria, folliculitis, etc. It is necessary to take treatment according to the specific cause after a clear diagnosis, such as general treatment, medication and so on. 1. Keratosis Pilaris: Keratosis Pilaris itself belongs to the follicular keratinization type of disease, mainly and heredity, lack of vitamin A, endocrine and other factors have a certain relationship, which may make the skin become rough, mistaken for arm pimples, usually there is no obvious discomfort symptoms, no special treatment, if the impact on the appearance of the use of retinoic acid cream under the guidance of the doctor for keratin exfoliation. 2. Urticaria: arm acne may be due to arm contact with allergic substances caused by papular urticaria, accompanied by itching, exclude the contraindications can be taken after the ice, taking loratadine, cetirizine and other antihistamines, topical hormone ointment and other treatments, if the rash indicates that there is a rupture, you need to fully disinfected topical rubbing of mupirocin, polymyxin B and other ointments to fight infections. 3. Folliculitis: arm acne may be due to local infection caused by folliculitis, you can use antibiotic ointment coating, such as mupirocin ointment, erythromycin ointment, etc., at the same time, pay attention to local hygiene, avoid scratching, so as to avoid large-scale infection. The causes of arm acne are different, the treatment is also different, the above drugs need to follow the doctor’s instructions to use, can not be used indiscriminately, so as not to cause adverse consequences, it is recommended that patients go to the hospital in a timely manner to improve the examination, a clear diagnosis, to give targeted treatment.