Itchy bumps on the arm after being sunburned is considered to be an allergy to ultraviolet rays caused by sun rash, can be relieved through general treatment and medication to alleviate the discomfort and improve the symptoms. 1. General treatment: It is recommended to avoid sun exposure, pay attention to daily sunscreen, wear long sleeves, eat a light diet, avoid spicy and stimulating food, quit smoking and drinking, avoid scratching, regular work and rest, and relax your mind. 2. Drug treatment: you can take oral loratadine, cetirizine and other antihistamines to relieve allergy symptoms, reduce itching; you can also use local glycerine lotion or mometasone furoate cream and other medication. Drugs are recommended to follow the doctor’s instructions, the emergence of adverse reactions to medical treatment, drug allergy is prohibited.