Infections can also cause hives. Respiratory infections caused by viruses are a common cause of hives in children. Other viral, bacterial, or fungal infections can also cause hives. In cases of chronic urticaria, the cause is much more difficult to determine. Very often, it is never identified.
Chronic urticaria caused by foods is more common in children than in adults.
If a food is identified as causing your hives, it should be removed from the diet. It is usually not difficult to tell when a person has hives. Hives can have irregular shapes and can be as small as a pencil eraser or as big as a dinner plate. The hives that appear cause considerable itching and can make a person extremely uncomfortable. The discomfort caused by hives can increase distress by making it difficult to sleep.