Sulfites are chemical preservatives used in a variety of foods, including beverages like wine and beer. They are added to processed foods to reinforce their expiry date and are even added to some medicines to guarantee their stability. Sulphites are likely to cause allergic reactions in some people, especially asthmatics. People who are sensitive to sulfites often experience allergic reactions similar to people with food allergies.
Symptoms of sulphite allergy.
Symptoms of sulphite allergy can be mild to moderate and very rarely severe. The main symptoms of sulphite sensitivity are:
- Digestive symptoms: diarrhea, stomach cramps, vomiting and nausea.
- Skin symptoms: redness and tingling of the skin, hives and itching.
- Respiratory symptoms: wheezing, difficulty breathing, cough, chest tightness.
- Anxiety, paleness and feeling tired
- Anaphylactic shock: Very rarely, a severe and life-threatening allergic reaction can cause low blood pressure and extreme difficulty in breathing, including loss of consciousness.
Foods and medicines containing sulfites
Some foods, such as Parmesan cheese and mushrooms, are high in sulfites. Canned food and beverages, including wine, cider, beer, sausages and soft drinks, are usually characterized by high sulphite content. Sulfites can be hidden in salad dressings in the form of vinegar or bottled lemon juice. Even in pizzas that use processed tomato sauce, and in olives.
Fresh fruits and vegetables, fresh meat and fish, fresh dairy products, freshly prepared sauces and seasonings are generally considered sulfite-free.
Sulfites can be present in prescription drugs for vomiting and nausea, antibiotics, psychotropic drugs, cardiovascular drugs, infusion drugs, drugs for respiratory problems, painkillers, steroids, and anesthetics.
Sulphite in the air.
Besides food and medicine, polluted air can also be a source of sulfite. Sulfur dioxide levels can be very high in the air near oil and coal burning plants, as well as in polluted air on foggy days. Exposure to sulfur dioxide in the air can cause bronchoconstriction, even in normal people. In people with asthma, even very brief exposure to sulfur dioxide can cause severe bronchoconstriction.
Diagnosis and treatment of sulphite allergy.
Sulphite hypersensitivity is usually diagnosed by exclusion and reintroduction of foods. This method consists of eliminating foods containing sulfites for a certain period of time. These foods are gradually reintroduced to see what reaction they might trigger.
Sulphite sensitivity is also diagnosed using a food challenge test. This involves ingesting a very small amount of sulfites while the subject is under the observation and close monitoring of an allergist. If there is a reaction, drugs are given to reverse the symptoms.
The only solution for a sulfite allergy is to avoid foods high in sulfites. Such as dried fruits, beer, wine and processed foods. It is very important to read product labels carefully so as not to consume foods containing sulfites. Ingredients to look for on food labels are:
- Potassium bisulphite (E228).
- Sulfur dioxide (E220).
- Sodium bisulphite (E222).
- Potassium metabisulphite (E224).
- Sodium metabisulphite (E223).
- Sodium sulphite (E221).
People with asthma should be extremely careful with foods that contain sulphite. Anaphylactic reactions following the ingestion of sulphites require immediate emergency treatment including an injection of epinephrine, followed by further procedures and observation in hospital. It is recommended that people who are extremely sensitive to sulfites always have epinephrine on hand.