Hives typically occur as an allergic response to something in your environment or something you ate. But they may sometimes happen because of an underlying health issue. Hives, also known as urticaria ...

Autoimmune hives (urticaria) are a type of rash caused by an overactive immune system that attacks healthy skin. It may be associated with an autoimmune condition, such as autoimmune thyroid disease.

Some people experience a flare-up of hives that goes away on its own. Other people may have hives that come and go daily. Hives are itchy, raised bumps on the skin. Doctors diagnose chronic hives in ...