Hives are generally a response to an allergen. You will need to give a few more doses of the Benedryl to elicit an effect. Keep an eye on things. When your child has an allergic reaction to something in the environment, it can take a turn for the worse. If he develops any wheezing or difficulty breathing, take him to the ER at your local hospital immediately. If he continues to break out in hives, you should get him his pediatrician for some other medications and evaluation of his allergy status.
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