Urticaria in children with fever manifests as a generalized red rash with significant itching. The main consideration is fever combined with systemic infection, bacteria produce some metamorphosis, will lead to the appearance of hives. If you have a high white blood cell count, you should check the calcitoninogen to make sure that the hives are really caused by an infection. After this is confirmed, antibiotics will be given to eliminate the infection so that the hives will be completely healed. It is also important to consider whether the allergic urticaria was caused by the use of antipyretic drugs or anti-inflammatory drugs when you had a fever. The main manifestation is that, after using a certain drug, within a day’s time, there is a whole body wind mass of red spots, and it will last for more than 24 hours, and the itching will be more severe.