Urticaria, commonly refers as hives is commonly caused by allergy. Affected skin area will rise slightly and the edge can be observed easily. Usually, it can be caused by insects’ bites and food allergy (i.e. eggs, shell food and nuts). Sometimes bacterial infection can cause hives, too.
Hives are itchy but immunosuppressants can help reducing the symptoms. When symptoms disappear, the skin will return to normal.
Most of the patients can heal without medication. But some will turn into chronic hives, and thus required to take immunosuppressants long term.