How is Sulfite Allergy Diagnosed?
While there have been some case reports of people being diagnosed with sulfite allergy using skin testing, there is no reliable, commercially available skin test for sulfite allergy. Typically, the diagnosis is suggested by a history of adverse reactions after consuming sulfite-containing foods or medications. However, in order for the diagnosis to be confirmed, an allergist may perform an oral metabisulfite challenge for a patient suspected of having sulfite allergy. This procedure involves giving a person increasing amounts of sulfites to swallow, with close monitoring of lung function and vital signs. A significant drop in lung function confirms sensitivity to sulfites. This test should only be performed under direct supervision of a physician who has been trained and is experienced with such a procedure.