It may be allergic dermatitis, peri-herpetic keratosis. Both manifest as bumps on the arms, but there are major differences in the course of the disease, in the presentation and symptoms, and in the treatment. Keratosis pilaris, also known as “chicken skin,” is a genetically related chronic skin manifestation that is not considered a disease. It may be related to follicle keratinization insufficiency, which is usually found at birth or shortly after birth, and is evident during adolescence, with similar rashes on the thighs and cheeks in addition to the arms. There is no need for special treatment, usually pay attention to more body lotions, especially those rich in fruit acids, or retinoic acid ointment, and eat more foods rich in vitamin A, or more carrots, etc. The actual fact is that you will not be able to get a lot of money from the company. Allergic dermatitis is mostly pruritic, appearing within a short period of time, unilateral or bilateral can occur, such as bilateral occurrence, consider and body diet, endogenous relationship, such as unilateral, consider the possibility of local contact caused by the possibility of anti-allergic treatment, recommended oral cetirizine tablets, Epastine tablets, loratadine tablets, choose 1-2 kinds, external use of Euzoil or Eloson ointment, life pay attention to not drinking alcohol, do not eat spicy The skin is a hereditary disease. Keratosis pilaris is a genetic disease, allergic dermatitis is an allergic disease, the symptoms are more different, identify clearly after the conventional treatment can be.