FOOD ALLERGY & INTOLERANCE

General Information

DEFINITION--Food allergy is an overreaction of the immune system to certain foods or substances that are otherwise harmless. These adverse reactions may be inborn or an acquired biochemical defect. Symptoms may occur within minutes or up to two hours after ingesting the food. In some instances, the symptoms may not appear until a day or two later. Food intolerance is mainly from an unknown cause, but may be due to irritants, toxins or food additives. More people have food intolerances than true food allergies. With intolerance, a person may consume small amounts of the offending substance without symptoms, such as milk intolerance.

BODY PARTS INVOLVED--Skin, lungs, gastrointestinal, central nervous system.

SEX OR AGE MOST AFFECTED--Males more often than females; all ages; food allergies are more common in children.

SIGNS & SYMPTOMS

• Diarrhea or abdominal pain (common).
• Flatulence and bloating (common).
• Skin rash; hives; itching.
• Swelling of hands and feet or face and lips.
• Hay fever; cough or wheezing.
• Nausea and vomiting.
• Asthma.
• Migraine headache.
• Fainting or near-fainting.

CAUSES--Any food or swallowed substance can cause allergic reactions. Foods most often involved are cow's milk, egg whites, wheat, soybeans, peanut, fish, tree nuts (walnut and pecan), shellfish, melons, sesame seeds, sunflower seeds, chocolate.

RISK INCREASES WITH

• People who have other allergy problems.
• Having family members with a history of food allergy.

HOW TO PREVENT

• Identify responsible foods and avoid them. Keep a food diary.
• Breast-fed infants who are started on solid foods late tend to have fewer allergies.

What To Expect

DIAGNOSTIC MEASURES--

• Your own observation of symptoms.
• Medical history and exam by a doctor.
• Elimination diets for both diagnosis and treatment.
• Skin tests may help identify the offending food, but frequently give results indicating that you are allergic to certain foods when you aren't.

APPROPRIATE HEALTH CARE

• Self-care.
• Doctor's treatment (severe reactions).

POSSIBLE COMPLICATIONS

• Anaphylaxis (difficulty in breathing, heart irregularities, blood pressure drop).
• Hive-like reaction.
• Bronchial asthma.
• Bowel inflammation.
• Eczema-like lesions.

PROBABLE OUTCOME--

• Infants will usually outgrow food hypersensitivity by 2-4 years of age.
• Adults with food hypersensitivity (particularly to milk, fish, shellfish or nuts) are more likely to maintain their allergy for many years.

How To Treat

GENERAL MEASURES--

• Eliminate the suspected foods from your diet for two weeks (or until all symptoms disappear) and then begin eating the foods again one by one to see if the symptoms return. Keep a diary and note the foods and any symptoms you feel.
• Patients with a severe allergy hypersensitivity to a food should be extra cautious in their avoidance of that food.
• Carry a kit with an adrenaline-containing syringe in case the offending food is eaten accidentally and a subsequent immediate reaction develops.
• Many fruit sensitive people may also have a reaction to latex (widely used in surgical gloves and medical devices as well as balloons, condoms, etc.) Advise any doctor or dentist about this reaction before any invasive medical procedure.
• Wear a Medic-Alert bracelet or pendant (See Glossary) that indicates your particular allergy.
• See Resources for Additional Information.

MEDICATION--No medication is available to treat food allergy, but medications may be prescribed to relieve some of the symptoms.

ACTIVITY--No restrictions.

DIET--

• Avoidance of the offending food, or limiting yourself to small amounts of it. Read food labels.
• Maintain a nutritionally balanced diet.
• Ask your doctor about a more advanced elimination diet if symptoms don't improve.

Call Your Doctor If

Someone appears to have a severe reaction after eating. Call for emergency help immediately.