Allergy Update
by P.K. Raghuprasad, M.D.

Sulfite Reactions

Sulfites are chemicals used to keep certain farm produce fresh longer.  Examples are lettuce and other vegetables that go into salads, and in some products such as potato chips.  They are found naturally in all wines and are also added to some wines as a preservative.  Shrimp, dried apricots and dried raisins also contain sulfites.  In some patients with asthma, ingesting sulfites may lead to an acute and sometimes life-threatening attack of asthma.  The presumed reason for this reaction is the inhalation of sulfur dioxide generated in the stomach by the interaction between the sulfites and the stomach acid.  All patients with asthma should be aware of this dangerous preservative intolerance and read labels of all food products.   This is so even thought the FDA has moved to ban the use of sulfites in food products (because compliance is by no means certain).