A person with a sulfite sensitivity is allergic to sulfites. Sulfites are natural substances that contain sulfur. Sulfites are used as preservatives or flavor enhancers in foods and medications.

Sulfites can be found in beer and wine, where they can occur naturally during fermentation. Sulfites have been banned from most fresh foods, but are still added to some processed foods.

Allergic reactions to sulfites seem to be more common in those who have asthma or allergic rhinitis.