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Allergy and Antihistamine Information Frequently Asked Allergy Questions How is an allergy diagnosed?
How is an allergy diagnosed?
Your doctor can diagnose if you have an allergy. After discussing your medical history and giving you a physical examination, the doctor can use skin tests to determine what you are allergic to. During the skin test, extracts of different types of allergens are used to scratch or prick the skin. If there is a reaction to that substance then this suggests an allergy exists.