A physician should be able to diagnose a person that has hives based upon their signs and the symptoms that the person has been experiencing, along with knowing the history of the patient’s allergies, if any.  Hives are usually not determined by laboratory tests.

Your healthcare provider can perform an exam of your body and question you about the hives.  Be sure that you speak with your health provider about any type of allergies you have, including foods, medicines, and insects.  If you physician thinks that a certain medication is causing the problem, then he or she may request you to discontinue using them. 

If your case of hives became a long-term issue, your healthcare provider might refer you to a dermatologist.  The dermatologist might be able to determine what the leading cause might be.  However, some people know what the cause of their outbreak was related to.