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Allergy to Sulfa Drugs

At the age of 42 I had my first allergic reaction to anything ever. I had been on Bactrim for a urinary tract infection and on Christmas Day, 1996, had to be admitted to hospital. I had hives, my face and lips were swollen, my hands ached and were so swollen that I couldn't turn a door knob, and it was difficult to swallow. They gave me adrenaline twice, and pumped unknown substances into me by IV. Nothing seemed to be working in the ER. They kept me overnight on an IV. It was an experience. I was okay by the next morning and was released. (They didn't tell me they were administering adrenaline, and they should have. I thought I was having a heart attack! I had absolutely zero knowledge about allergies)

I know that some people are allergic to sulfites, which are a food additive. Are sulfites something I should avoid?

I don't seem to have had any problem with any foods, but I wonder if I should stay away from them, considering my reaction to a sulfa drug.

Are these two different things?

Thank you,

Valerie G.

Dear Valerie:

Thank you for asking about the possible relationship between allergy to sulfa antibiotics and sensitivity to the food preservative metabisulfite.

These are two separate and distinct types of reactions which do not appear to cross-react. An allergic reaction to sulfa medications does not mean that shellfish need to be avoided as well since there is no "sulfa" in shellfish.

A sulfite induced reaction is not believed to be due to an allergic immune [antibody type] mechanism. Sulfites in the sulfite-sensitive patient can cause an immediate reaction including swelling of the throat and spasm of the airways (asthma).

To review, sulfite reactions are not based upon an immune reaction and sulfa reactions are.

I hope this info is useful to you.
Good luck.

Steve Kagen, M.D.
Allernet.com