The Oral allergy syndrome is an allergic reaction that specifically affects the mouth, lips, tongue, and throat. It is associated with allergic rhinitis, otherwise known as hay fever.
In oral allergy syndrome, the body cross-reacts to certain proteins in certain foods. This protein is similar to a protein found in pollen associated with fever and seasonal allergies.
Since these foods are usually available throughout the year, oral allergy syndrome is not seasonal.
Oral Allergy Causes
Protein is found in all organic matter. The immune system identifies specific proteins to target bacteria, viruses, and other unwanted germs. However, it sometimes identifies everyday proteins, such as pollen, as dangerous targets.
Once eaten or inhaled, these proteins are available in large quantities and the immune system identifies them as abnormal. The body reacts with a significant immune response, which leads to swelling, a variety of other allergy symptoms, and discomfort.
For many people, the main signs of oral allergy syndrome are swelling and itching of the lips, mouth, tongue, and throat immediately after eating certain fruits and vegetables, especially when raw.
Experts estimate that more than 60 percent of all food allergies are actually cross reactions to pollen allergies. The most common cause of allergic rhinitis in the United States is birch pollen. However, many trees, grasses, and weeds can cause it as well.
Usually, oral allergy syndrome can be traced back to allergies as follows:
- Japanese Cedar
- Plane tree
- Garden grass
- Parietaria species
Common foods that cause oral allergy syndrome
Since there are various possible causes of allergic rhinitis, there are also a variety of fruits and vegetables that cause oral allergic syndrome.
Similarly, different fruits and vegetables can cause different responses depending on the type of pollen cross reaction system. According to a paper in the Journal of Allergy, typical foods that can cause reactions include:
- Genus Prunus: cherry, nectarine, peach, plum, apricot
- Apples and pears
- Apiaceae family: celery, carrot, parsley, parsnip, coriander leaves, cumin, dill, chervil, and fennel.
- Nightshades: tomatoes, potatoes and peppers
- Cucurbitaceae family: pumpkin, butternut squash, zucchini, cucumber
- Hazelnuts and walnuts
- Sunflower seeds
Oral Allergy Symptoms
Most people with OAS have symptoms such as itching, burning, tingling, and swelling of the mouth, mouth, tongue, and throat where fresh fruit or vegetables are touched. Symptoms usually only last from second to few minutes and rarely develop into nothing more serious.
However, some studies show that up to 9 percent of people with OAS may experience more severe symptoms of food allergy, and up to 2 percent may suffer from anaphylaxis. Because of this, some authorities suggested changing the name to pollen syndrome. Symptoms are more likely to occur and become more severe during the season in which responsible consensus is found.
Oral allergy syndrome prevention
There are various ways that can be done to prevent the onset of allergies such as:
- Avoid foods such as fruits or vegetables that can trigger the onset of allergies.
- If you want to eat it, then cook the fruit or vegetables because it can break down or change existing proteins so that the immune system will not attack it.
- If you want to eat fruit, then peel the skin because most of the allergy-triggering proteins are in the skin.
Oral Allergy Treatment
The best treatment for oral allergy syndrome is very easy: Avoid your trigger foods.
Over-the-counter histamine inhibitors, or antihistamines, used for fever can work for symptoms of oral allergy syndrome, according to a paper published in Allergy. Diphenhydramine (Benadryl) and fexofenadine (Allegra) can be used to relieve itching, watery eyes, and throat itching that come on days with high pollen for allergy sufferers. They can sometimes suppress OAS reactions as well.
People treated with immunotherapy for OAS have mixed reactions. In one clinical study, subjects were able to tolerate a small number of birch ciders after immunotherapy, but they were unable to fully address OAS symptoms.
Since OAS symptoms are harmless, ask your general practitioner if you can do occasional experiments and see your reaction.