HIVES - Also known as urticaria, this allergic skin eruption is characterized by multiple, circumscribed, smooth, raised, pinkish, itchy welts that can develop very suddenly almost anywhere on the body. Have also been known to develop in response to cold, heat, animal dander, insect bites, pollen, or stress. Treatment often includes antihistamines and Adrenalin. Some individuals may also be given corticosteroids.