Your child has hives when:
Your child may get hives if he has an infection. Your child may be allergic to a food, medicine or to bee stings. This can cause the hives. Hives do not spread to other people. They come and go for a few days and then go away.
Be sure to keep giving the medicine until you are sure the hives are completely gone for 12 hours. Otherwise your child may get itchy again.