With spring in full bloom and the pollen dropping we are bringing back a timely discussion on seasonal allergies with allergist and immunologist Dr. Anh Nguyen. We discuss why environmental allergies develop, and why they are worse in some geographic areas. We review common symptoms and how to differentiate them from illness.  We review how the diagnosis of seasonal allergies is made and how they can be treated, from over-the-counter antihistamines to targeted allergy shots and oral immunotherapy.