People can experience allergic reactions to things such as animal dander, bee stings, chemicals, and foods, which can result in hives, itching, rash, and other symptoms. The National Library of Medicine recommends these first aid steps for mild-to-moderate reactions: calm and reassure the person having the reaction; try to identify the allergen and have the person avoid additional contact with it; if the person develops a rash, apply a cool compress and hydrocortisone; and watch the person for signs of increasing distress. If the allergic reaction is severe, you should summon emergency services immediately. National Library of Medicine, January 2020