Review of sulfite sensitivity

The occurrence of sulfites in foods, drug products, and the environment; the characteristics of sulfite-sensitivity reactions; and the management of sulfite-sensitive individuals are reviewed. Sulfites are used in foods, beverages, and pharmaceuticals for their antioxidant properties; they are frequently used in restaurant foods to keep vegetables and fruits looking fresh. Beer, wine, and dried, canned, or frozen fruits often contain sulfites, and seafood and fried potatoes are often prepared with these agents. Sulfites are also present as pollutants in the atmosphere. The incidence of sulfite sensitivity is unknown, but the condition is being recognized with increasing frequency. Bronchospasm is sometimes induced by sulfites in sensitive individuals, and anaphylaxis and death have been reported. Immediate or delayed reactions may occur. The mechanism of toxicity is unknown but is thought to be sulfite-induced stimulation of the afferent limb of the cholinergic reflex. Clinical management is based on avoiding strenuous exercise on days when atmospheric pollution is high and on avoiding foods and drug products containing sulfites. Treatment of sulfite-sensitivity reactions is usually supportive; subcutaneous epinephrine has been effective in some patients. Several drugs have been used investigationally to prevent sulfite-sensitivity reactions. However, few data are available to evaluate their efficacy. Sulfites may induce bronchospasm and anaphylaxis in sensitive individuals. These people should avoid foods and drug products containing sulfites.