Oral Allergy Syndrome

Do you ever get an itchy mouth, tongue and lips when eating apple, celery, peach or watermelon?  If so, you could be included in the up to one-third of allergy sufferers who’s pollen allergy sets them up to react to particular foods.

If you suffer from hay fever and have experienced an itchy mouth or scratchy throat after eating certain raw fruits or vegetables and some tree nuts, you may have oral allergy syndrome (OAS).

Oral allergy syndrome, also known as pollen-food syndrome, occurs because the proteins found in some fruits and vegetables are very similar to those found in pollen. These proteins can confuse your immune system and cause an allergic reaction or worsening of existing allergy symptoms.

Individuals react to different foods based on the type of seasonal allergies they are affected by. Examples of this cross-reactivity;  if you are allergic to birch tree pollen, a primary airborne allergen responsible for allergy symptoms in the springtime, you may have oral allergy reactions triggered by almond, apple, carrot, cherry, cucumber, hazelnut, kiwi, parsley,  peach, pear and plum.

An allergic person who gets a runny nose or drippy, itchy eyes when exposed to ragweed pollen in the late summer and fall might develop an itchy, tingling mouth or lips when eating foods with similar proteins. Examples of food and ragweed pollen cross-reactivity are banana, cucumber, melon and zucchini.

Similarly, people with allergies to airborne grasses may have an oral allergy reaction when eating celery, peach, banana, melon, tomato, orange and kiwi.

Oral allergy syndrome symptoms appear soon after the food is eaten and symptoms are usually limited to the mouth, tongue, lips and pass away quickly. Research demonstrates up to 9% of patients with oral allergy syndrome can potentially develop a serious, severe allergic reaction called anaphylaxis that will require immediate emergency treatment.

Symptoms can seem quite random. Many people are only bothered during the pollen season; the rest of the year they can eat pollen-related foods with no problem. So if they are allergic to ragweed, eating a melon in February (when ragweed is dormant) may not bother them at all, while eating melon in September (when ragweed pollen counts are high) could set off symptoms with the first bite. Other patients report that they can eat cooked but not raw fruits and vegetables or can tolerate them if the peel is removed.

Children and adults can develop oral allergy syndrome even if they have eaten these foods previously without problems. Also, parents might not associate a child’s dislike of a vegetable or fruit with an allergic reaction.

Food-related symptoms can sometimes alert you to a more dangerous allergy such as latex. A board-certified allergist can give you an accurate diagnosis using a thorough history, skin testing, or oral food challenge advising you which foods to avoid and recommend treatments to relieve your symptoms. This treatment could include a prescription for an epinephrine auto-injector to treat potential severe reactions.