Why do you suddenly have hives?

Urticaria is a common allergic skin disease. It can be divided into acute and chronic urticaria according to the course of disease. Most patients cannot find the exact cause, especially chronic urticaria. The most common cause is diet, mainly including animal protein.(such as fish, shrimp, crab, meat, milk and eggs), plant food (such as mushrooms, strawberries, cocoa, tomatoes and garlic) and certain food condiments and additives. In addition, drugs, infections, various physical factors (such as cold, heat, sunlight, friction and pressure, etc.), animal and plant factors, mental stress, internal organs and certain medical diseases can also cause urticaria. Regular oral anti-allergic drug treatment is required. Severe cases need to be treated by short-term glucocorticoids in hospital.