If you are currently traveling outdoors and have been exposed to the sun for a long period of time and are not wearing long-sleeved clothing, you cannot rule out sun dermatitis caused by UV allergies. In the treatment of solar dermatitis, it is recommended to avoid direct sunlight, wear long-sleeved clothing and apply cold compresses locally. If the arms and other parts of the body may have red spots, papules or even small blisters, and will be accompanied by significant itching, it is considered eczema, which is an allergic skin problem, so in the treatment of allergies, it is recommended to avoid spicy, seafood and beef, mutton and other foods, and avoid hot water for scalding, which will lead to itching and rash aggravation, in the parts of the bumps can be applied topically Denide or Elocon Anti-allergy and anti-itch treatment.