Small rice-sized bumps on the arm is not red and itchy, may be folliculitis, solar dermatitis, psoriasis, etc., need to be on the cause of the drug or physical therapy. 1. For folliculitis caused by, can follow the doctor’s instructions external mupirocin ointment ointment, oral amoxicillin and other antibiotics; available far-infrared irradiation and other physical methods to promote the inflammation subside. 2. For solar dermatitis caused by, can follow the doctor’s instructions for external miconazole cream or pimecrolimus ointment. Systemic medication can be oral hydroxychloroquine, niacinamide, β-carotene is effective for some patients; severe cases can be oral glucocorticoids or cyclosporine. 3. For psoriasis caused by, can follow the doctor’s instructions for external use of carbotriol, tacrolimus ointment, oral methotrexate and other inhibitors of cell proliferation drugs, etc.; ultraviolet irradiation can inhibit the immune response, promote the recovery of skin lesions. It is recommended that people with small rice-sized bumps on their arms that are not red and itchy go to the hospital in a timely manner to clarify the cause of the disease and standardize the treatment under the guidance of the doctor to avoid delaying the condition.