Many of my patients wonder whether preservatives are playing a role in their allergies, particularly hives. This was a hot topic in the allergy world in the 80’s and early 90’s. The most commonly implicated preservative was sodium metabisulfite, which is found in a wide variety of foods. Because it is so common, it became a target for unexplained, chronic hives. When it was studied using blinded, placebo-controlled oral challenges, very few true reactions were observed. Both Dr. Norvell and I trained at Vanderbilt where we had the occasion to supervise many such challenges. Since many people remain concerned about reactions to metabisulfite and other preservatives, at the AAAMT we canperform blinded, placebo-controlled oral challenges if the situation warrants. This remains the gold standard way to evaluate for the presence of preservative, and other, allergies.