The following symptoms may occur after eating an offending food:

• scratchy throat
• anaphylaxis (a severe, whole-body allergic reaction that can result in death)
• abdominal pain
• diarrhea
• nausea
• vomiting
• stomach cramps
• itching of the mouth, throat, eyes, skin, or any area
• hives
• angioedema (swelling, especially of the eyelids, face, lips, and tongue)
• light-headedness or fainting
• nasal congestion
• runny nose
• shortness of breath
• wheezing
• difficulty swallowing

THE ORAL ALLERGY SYNDROME

The oral allergy syndrome consists of itching lips, tongue, and throat, and sometimes swollen lips. It occurs after eating certain fresh fruits and vegetables. The allergens in these foods are similar to certain pollens. Examples are Melon/Ragweed pollen and Apple/Tree pollen. While people with oral allergy syndrome rarely have an anaphylactic reaction, they should ask their doctor whether they need to carry injectible epinephrine.

If you develop symptoms shortly after eating a specific food, you may have a food allergy. Key signs include hives, hoarse voice, and wheezing. In severe reactions, you may have low blood pressure and blocked airways.

A blood test to identify elevated antibody levels (particularly IgE) can confirm that you have an allergy.

The food causing the allergy can sometimes be identified by:

• Food elimination diets -- the suspected food is eliminated from the diet until the symptoms disappear, then reintroduced to see if allergic reaction develops. This method is not foolproof but may be used to narrow the list of suspected foods.
• Food provocation diet.
• Skin tests.
• RAST test -- blood tests for antibodies to a specific allergen.

Never try deliberately causing a reaction, or reintroducing a food, on your own. These tests should only be performed under the guidance of a physician -- especially if the initial reaction was severe.