Itchy arms scratching out small bumps is considered to be insect bite dermatitis, artificial urticaria, allergies, etc., according to the specific causes of the choice of the appropriate medication to apply. 1. Insect bite dermatitis: this is an allergic reaction to insect bites, if the symptoms are not particularly serious, usually disappear in a few days, if the itching is heavy, you can apply peppermint glycerite lotion to stop the itching, if necessary, you can apply glucocorticosteroids, such as hydrocortisone cream, mometasone furoate cream. 2. Artificial urticaria: Artificial urticaria is mainly the skin after scratching or scratching, there are strips of bulging or redness, you can use emollients, such as Vaseline, Vitamin E cream, the symptoms are more serious, it is recommended that oral antihistamines such as cetirizine, ibogaine and so on. 3. Allergy: If you eat allergic food or contact with allergic substances, this symptom can also occur, you can apply glycerine lotion, the more serious symptoms can be applied halometasone cream, mometasone furoate cream, but also oral benadryl, ipecac, and so on. There may be other reasons for itching and scratching out small bumps on the arms, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment. All of the above drugs should be used in accordance with the doctor’s instructions, can not be used blindly.