There are a lot of small bumps on the arm should be dealt with according to the cause of the disease, if it is keratosis pilaris can be treated with medication, if it is eczema can be treated with general treatment and medication, if it is mite infection can be treated with general treatment and medication. 1. Keratosis pilaris: if it is caused by keratosis pilaris can be treated with medication, can follow the doctor’s instructions for topical use of retinoic acid cream, salicylic acid ointment and other drugs for local treatment, but also with oral medication such as vitamin A, vitamin E and so on. 2. Eczema: the general treatment of eczema requires the reduction of external stimuli, avoid contact with irritating substances, eat a light diet, medication can be used under the guidance of a doctor, such as glycerite lotion, but also oral medications such as cetirizine, loratadine and so on. 3. Mite infection: arm skin infection mites will also appear small bumps, general treatment includes attention to personal hygiene, away from mites environment, keep the skin clean, medication can be used topical sulfur ointment and other drugs for treatment. A lot of small bumps on the arm may also be caused by other reasons, it is recommended that patients go to the hospital in a timely manner, to clarify the cause of the disease under the guidance of the doctor’s treatment. The application of drugs need to strictly follow the doctor’s instructions, if there is discomfort can stop the drug to consult the doctor.