Definition

Sulfites are compounds that are used to make foods and beverages last longer. Sulfite sensitivity is an abnormal reaction to these compounds.

Foods that may contain sulfites include:

• Beer, wine, and soft drinks
• Cookies, crackers, pie crust, and pizza crust
• Dried fruit
• Shrimp, lobster, and scallops
• French fries and other food made with peeled potatoes, such as instant mashed potatoes
• Fruit or vegetable juice
• Canned fruits or vegetables
• Syrup and fruit toppings
• Pickles, relish, olives, and salad dressing
• Noodle or rice mixes
• Dried soup mixes
• Deli meats, mince meat, sausages

Many prescription and over-the-counter medications also contain sulfites. Sulfites are also contained in products applied to the skin, such as cosmetics.

Causes

It is not clear what causes a sulfite sensitivity to develop. It may be due to genetic and environmental factors.

Risk Factors

There are no known risk factors for sulfite sensitivity. Most people with sulfite sensitivity have asthma.

Symptoms

Most symptoms are mild and can vary based on your body’s reaction to sulfite ingestion. It may be one or a combination of the following:

When the stomach breaks down sulfites, it releases a sulfur dioxide gas. This gas can pass up into and irritate airways in some people, such as those with asthma. This can cause symptoms such as:

• Wheezing
• Coughing
• Shortness of breath

Some people may lack the enzyme needed to breakdown sulfites. This can cause:

• Abdominal pain
• Nausea
• Diarrhea

Some may also have an allergic reaction to sulfites. This means sulfites cause an autoimmune reaction, which may cause:

• Skin rash
• Skin inflammation

Diagnosis

Your doctor will ask about your symptoms and medical history. A physical exam will be done. The doctor may ask specific questions about what you were doing when the symptoms occurred. The exact cause may not be clear in the first visit. Your doctor may ask you to keep a diary of your symptoms to help determine the cause.

Your bodily fluids and tissues may be tested to eliminate other causes. This can be done with:

• An allergy skin test
• Blood tests

You may also be asked to avoid certain foods or beverages for a short period of time to see if symptoms go away. This is called an elimination diet and can help find out what is causing your symptoms.

Treatment

Symptoms can be reduced or eliminated by avoiding foods or drinks that contain sulfites.

To reduce sulfite intake:

• Read the ingredient label on every food product that you eat.
• Learn the other names for all your allergens. This will help you recognize them on an ingredients list.
• If you go to a restaurant, discuss your allergy with the food server. Ask about all ingredients.
• Be aware that food may become contaminated by shared utensils and containers. It may also become contaminated during preparation.
• Read drug labels carefully. If you have any questions, talk to your doctor or pharmacist.
• If you have a severe allergy, ask your doctor if you should carry a dose of epinephrine with you.

Consider wearing a medical alert bracelet to inform others of your allergy. If you have difficulty breathing, call for medical help right away.

Medications may be given or advised to help ease breathing or treat other allergic symptoms such as:

• Antihistamine medication to decrease swelling and itching
• Corticosteroid medication for more severe swelling and itching
• Epinephrine injection to treat a severe, life-threatening reaction
• An inhaler to deliver medication to help open your airways if you also have asthma

If you have a confirmed sulfite allergy, consider seeing an allergy specialist.

Prevention

There are no known steps to prevent sulfite sensitivity, because it is unclear what causes sulfite sensitivity to develop.

Food Allergy and Anaphylaxis Network http://www.foodallergy.org

Health Canada http://www.hc-sc.gc.ca

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