Allergies Food Allergies Causes & Risk Factors Sulfite Allergy Overview and What to Avoid A food additive that can trigger asthma symptoms By Daniel More, MD Updated on May 04, 2023 Medically reviewed by Daniel More, MD Print Table of Contents View All Table of Contents Causes Foods to Avoid Drugs to Avoid Diagnosis Treatment Sulfites are chemicals found in certain foods that can cause allergy symptoms in some people, including wheezing, coughing, and flushing. These sulfur-based compounds occur naturally in foods like wine and molasses but are also added to food to enhance flavor or act as a preservative. Sulfite allergies can range from mild to severe. On rare occasions, sulfites can even trigger a potentially life-threatening, whole-body allergic reaction known as anaphylaxis. This article explains the cause of a sulfite allergy and offers a list of foods and medications that contain sulfites. It also explains how sulfite allergies are diagnosed and treated, including the signs and symptoms of a medical emergency. What Is a Sulfite Allergy? A sulfite allergy, like all allergies, is the result of an abnormal immune response to an otherwise harmless substance (known as an allergen). Sulfites are chemical compounds that are found naturally in some foods but are also manufactured for commercial use as a food preservative or flavor enhancer. An allergy to sulfites can happen to anyone but is most common in people living with asthma. Illustration by Joshua Seong. © Verywell, 2018. For reasons that are not entirely clear, some people have a hypersensitivity to sulfite. In these people, the immune system will respond to sulfites as if they were a threat, releasing a defensive protein called immunoglobulin E (IgE) into the bloodstream. IgE, in turn, causes specialized immune cells, known as basophils and mast cells, to break open and flood the body with an inflammatory compound called histamine. Histamine is the main compound that causes allergy symptoms. It does so by spurring inflammation in the skin and mucosal tissues of the respiratory and digestive tract. When this happens, blood vessels will dilate (widen) and release fluids into surrounding tissue, causing them to swell. This cascade of events can cause asthma-like symptoms, ranging from mild to severe, including: WheezingChest tightnessCoughingShortness of breath In severe cases, sulfite hypersensitivity can trigger symptoms of anaphylaxis, including: FlushingSudden rash or hivesRapid, weak pulseDifficulty swallowingDifficulty breathingSevere abdominal painNausea and vomitingSevere diarrheaLightheadedness or faintingSwelling of the mouth, throat, or neckA feeling of impending doom When to Call 911 Anaphylaxis requires immediate emergency care without exception. Symptoms tend to develop within 30 minutes of consuming sulfites. If not treated appropriately, anaphylaxis can lead to shock, coma, heart or respiratory failure, and death. Foods to Avoid Sulfites are found in many foods. Some are naturally occurring, while others are added. Sulfites used to be added to fresh foods in restaurants and grocery stores to prevent browning. An increase in allergic reactions led the U.S. Food and Drug Administration (FDA) to ban their use in fresh vegetables and fruits back in 1986. The FDA now requires manufacturers to declare on product labels if their food contains more than 10 parts per million (ppm) of sulfites. (Foods containing less than 10 ppm haven't been shown to cause symptoms, even in people with known sulfite allergies.) Greater Than 100 PPM Foods with sulfite levels greater than 100 parts ppm are considered very high in sulfates. If you have a sulfite allergy, you should strictly avoid these: Bottled lemon juice (non-frozen)Bottled lime juice (non-frozen)Dried fruits (except for dark raisins and prunes)Grape juices (white, white sparkling, pink sparkling, red sparkling)MolassesPickled cocktail onionsSauerkraut and its juiceWine Between 50 and 99.9 PPM These are considered moderate to high sulfite levels. If you have a sulfite allergy, you're advised to avoid these: Dried potatoesFruit toppingsGravies/saucesMaraschino cherriesWine vinegar Between 10 and 49.9 PPM These foods contain low to moderate levels of sulfite but can still cause symptoms in people with severe sulfite allergy: Avocado dip/guacamole Cheese (various) Ciders and cider vinegar Clams (canned or jarred) Clam chowder Cordials (alcoholic) Corn syrup Cornbread/muffin mix Cornstarch Dehydrated vegetables Fresh mushrooms Hominy Imported fruit juices and soft drinks Imported jams and jellies Imported sausages and meats Maple syrup Pectin Pickled peppers Pickles/relish Potatoes (frozen) Shrimp (fresh) Less Than 10 PPM These foods have very low sulfite levels and pose little to no risk in people with sulfite allergy: Beet sugarBeerCanned potatoesCoconutCookiesCrackersFruit salad, freshFrozen pizza and pie doughGelatinGrapesHigh fructose corn syrupJams and jellies, homemadeMalt vinegarSoft drinksSoup mix, dry Other Names for Sulfites There are several different sulfites used as food additives in the United States, including:Sodium sulfiteSodium bisulfiteSodium metabisulfitePotassium bisulfitePotassium metabisulfiteSulfur dioxideIf you have a sulfite allergy, check product labels to see if any of these are included. The Most Common Food Allergens Medications to Avoid Sulfites are sometimes added to medications as a preservative, but this doesn't necessarily mean that you should avoid the drugs. In cases like these, the benefits of the drug may outweigh the risks. One such example is the EpiPen (epinephrine auto-injector) used to treat an anaphylactic reaction. Because an EpiPen can save a person's life, the risks of a sulfite allergy tend to pale by comparison. If you have a known allergy to sulfites, speak to your healthcare provider about the possible risks of using any of the following inhaled, topical, or injected medications: Bronchodilator Solutions for Asthma Adrenalin chloride 1:1000 concentration (epinephrine)Bronkosol (isoetharine)Isuprel (isuprel hydrochloride) Topical Eye Drops AK-Dex, Ocu-Dex (dexamethasone)Bleph-10 (sulfacetamide sodium)Pred-Forte (prednisolone acetate)Pred-Mild (prednisolone) Injectable Medications Adrenaline, Ana-Kit, EpiPen (epinephrine)A-Hydrocort, Solu-Cortef (hydrocortisone-injectable)Amikin (amikacin)Aramine (metaraminol)Celestone (betamethasone phosphate)Compazine (prochlorperazine) Decadron (dexamethasone phosphate)Demerol (meperidine)DopamineGaramycin (gentamycin)Isoetharine HClIsuprel (isoproterenol-injectable)Levophed (norepinephrine)Nebcin (tobramycin)Novocaine (procaine)Phenergan (promethazine) Solutions for total parenteral nutrition and dialysisThorazine (chlorpromazine) Xylocaine with epinephrine (lidocaine with epinephrine) How Is Sulfite Allergy Diagnosed? Sulfite allergy rarely shows up in allergy skin tests. It is diagnosed based on a history of bad reactions to sulfites. To confirm the diagnosis, your allergist may have you perform an oral challenge. You'll ingest increasing amounts of sulfites while your lung function and vital signs are monitored. A significant drop in lung function confirms the sensitivity. This test should only be done under the direct supervision of a healthcare provider who is trained and experienced with the procedure. How Is Sulfite Allergy Treated? If you have (or suspect having) a sulfite allergy, the best form of treatment is to avoid foods and medications that contain them. The FDA label mandate makes this fairly easy. If an allergy does occur, the treatment can vary based on how severe your hypersensitivity is. Some of the more common treatment options include: Oral antihistamines: These drugs, available over-the-counter and by prescription, block the effects of histamine. Options include Allegra (fexofenadine), Claritin (loratadine), and Zyrtec (cetirizine). These tend to work best for milder cases. Rescue inhalers: These medications, called bronchodilators, contain a medication called albuterol that is inhaled to relieve severe asthma symptoms. Oral corticosteroids: These drugs, also known as steroids, can quickly reduce inflammation in people with severe reactions. A short course of prednisone is most commonly used. Sodium cromoglycate: These oral drugs, delivered in capsule form, can be useful in helping ease severe asthma reactions caused by exposure to sulfites. EpiPen: The epinephrine auto-injector is given to people at high risk of anaphylaxis to quickly reverse symptoms until emergency help arrives. If you have a history of anaphylaxis, always carry two EpiPens with you (in case one doesn't work or one dose is not enough). You should also wear a MedicAlert bracelet. Summary Some people are allergic to sulfites found in foods or used as food additives. This can cause asthma-like symptoms or, on rare occasions, a potentially life-threatening allergy known as anaphylaxis. If you have a sulfite allergy, the best thing you can do is to avoid foods and certain medications that contain them. The FDA requires manufacturers to advise consumers if sulfites are higher than 10 parts per million (ppm). Oral, inhaled, or injected medications can be used to treat a sulfite allergy, including antihistamines, oral steroids, rescue inhalers, and an EpiPen auto-injector. Adverse Reactions to Food Additives and Preservatives 7 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. American Academy of Allergy, Asthma, and Immunology. Allergic reactions. Lien KW, Hsieh DPH, Huang HY, Wu CH, Ni SP, Ling MP. Food safety risk assessment for estimating dietary intake of sulfites in the Taiwanese population. Toxicol Rep. 2016;3:544–51. doi:10.1016/j.toxrep.2016.06.003 Fischer D, Van der Leek TK, Ellis AK, Kim H. Anaphylaxis. Allergy Asthma Clin Immunol. 2018;14(Suppl 2):54. doi:10.1186/s13223-018-0283-4 Vally H, Misso NL. Adverse reactions to the sulphite additives. Gastroenterol Hepatol Bed Bench. 2012;5(1):16–23. Federal Register. New method for the analysis of sulfites in foods. Bold J. Considerations for the diagnosis and management of sulphite sensitivity. Gastroenterol Hepatol Bed Bench. 2012;5(1):3–6. Miyata M, Schuster B, Schellenberg R. Sulfite-containing Canadian pharmaceutical products available in 1991. CMAJ. 1992;147(9):1333-8. Additional Reading Sampson HA, Aceves S, Bock SA, et al. Food allergy: a practice parameter update-2014. J Allergy Clin Immunol. 2014;134(5):1016-25.e43. doi:10.1016/j.jaci.2014.05.013 U.S. Food & Drug Administration. Guidance for industry: Food labeling guide. PDF available for download. By Daniel More, MD Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and formerly practiced at Central Coast Allergy and Asthma in Salinas, California. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit