A food allergy is an adverse immune response to a food protein. Just as the body can be allergic to dust, mold and pollens, it can have a similar response to food proteins. This can lead to many uncomfortable allergy symptoms. Food allergy tends to be hereditary and is common in people with environmental allergies (to pollen, dust, mold, etc.) The condition is increasingly recognized as a significant health burden worldwide and has substantial negative effects on health and quality of life for affected persons.

Signs of food allergy:

Food allergy should be considered when allergic symptoms occur within minutes to hours after ingestion of a specific food, especially when symptoms occur on more than 1 occasion.

Common food allergy symptoms:

Diagnosing food allergy:

Medical history is key in diagnosis, and it's very important for physicians to take a judicious history in the context of knowledge about food allergy and then judiciously select tests that make sense to confirm suspected allergies.

Diagnostic dilemma:

A serious misconception about food allergy diagnostics relates to equating a 'positive test result' by a serum food-specific [immunoglobulin E] (sIgE) blood test or skin prick test...to having an allergy to the tested food. These tests detect IgE antibodies to the food but are not typically intrinsically diagnostic.

However, physicians also risk under-diagnosing or misdiagnosing a true food allergy. Without confirmatory testing, an allergen could incorrectly be identified as the culprit, leading to a serious reaction if the child is again exposed to the true allergen.

Physicians involved in pediatric care also need to remember that not all food allergies evolve from the production of IgE antibodies, and these will be missed on IgE antibody-based tests. Examples of non-IgE-mediated allergies include protein-induced enterocolitis, symptoms of which start 2 hours after

ingesting the offending food allergen, and allergic colitis, characterized by mucous-containing bloody stools.

Definitive Test

The oral food challenge or feeding test is the definitive test to confirm an infant or child really does have a food allergy. But in the vast majority of cases, a food allergy can be excluded or diagnosed with good accuracy when you put together a careful history and [either sIgE or skin prick] testing. A feeding test is really only needed when the patient's history or test results or both are ambiguous.

Treating food allergy:

Avoidance is the mainstay of management of food allergies, and is advised for most adults with food allergies but in fact, for infants there is increasing evidence that waiting longer and longer to introduce allergenic foods might actually pose risk.

Now, evidence supports much earlier introduction of allergenic foods, especially for infants at the highest risk for food allergy (namely, those with severe eczema or egg allergy). Additionally, there is little evidence that elimination of allergenic foods by pregnant or lactating women prevents future food allergies in their infants.

If you’re tired of simply avoiding the foods that cause your allergy symptoms, there is promising news. There is just one treatment that has been shown to improve allergic disease: allergy immunotherapy. Other treatments may help with symptoms, but they don’t affect the root of the problems. Allergy immunotherapy used to be available only through allergy shots, but shots weren’t a good treatment option for everyone. Shots are painful and also time consuming since they must be administered in a medical clinic-often twice per week. Shots also pose a risk of an anaphylactic reaction.

New medical studies have validated a treatment called sublingual immunotherapy (SLIT) as a useful approach to reducing allergy symptoms. With sublingual immunotherapy, drops of allergenic extracts designed to desensitize the body to specific substances is dispensed under the tongue (rather than injected into the skin). Once under the tongue, it is absorbed into the blood flow through cells in the mouth. These allergy drops offer the benefits of allergy immunotherapy without the hassle of shots. They are also safer than shots with a markedly decreased risk of anaphylactic reaction, allowing for home administration. This increased safety record allows allergy drops to be prescribed to kids too young to be eligible for shots.

Another advantage is that doctors can prescribe sublingual immunotherapy for food allergies (something allergy shots don’t treat). Allergy drops have shown to be effective in safely treating food allergies to milk, eggs, certain nuts, wheat, fruit, rice, soy, etc. The allergy drops also work for cat and dog allergies as well as pollen, mold, and dust allergies.

Oral immunotherapy (OIT) is yet another treatment modality which has shown promise for the treatment of food allergies. OIT involves the daily administration of food allergens (milligrams to grams) mixed with a food vehicle in gradually increasing doses over months to years. OIT has been studied in several clinical studies for more than a decade involving mainly milk, egg and peanut allergies. Recent trials have provided invaluable efficacy and safety data as well as compelling evidence that OIT frequently induces desensitization, and possibly even tolerance, in patients with food allergies.

For the allergy treatment program to be fully effective, allergy drops must be taken daily with consistency. The allergy drops contain natural extracts of the most common allergens. As patients take the drops, the body learns to “make peace” with these allergens and stop overreacting to them. In essence, the body develops an immunity to the offending allergens.

Emergency Management

In emergencies, epinephrine is the treatment of choice. If epinephrine is underutilized, bad outcomes may happen but, when used promptly, epinephrine reduces the need for additional doses, it reduces hospitalization, and presumably also mortality.

Conclusions

Food allergy is an increasingly prevalent disorder with no definitive cure or approved treatment. Patients living with food allergies are at risk of accidental ingestions daily that can result in potentially life-threatening reactions.

Over the past decade, several studies have demonstrated the ability of OIT and SLIT to induce desensitization, in which patients are able to tolerate the ingestion of more food allergen while on treatment, and positive immunologic changes with ongoing therapy. However, concerns and questions still remain, necessitating further research to address the safety and efficacy of OIT and SLIT for long-term use.

Allergy World clinics offer under-the-tongue serum drops that contain extracts of more than 50 different food items. Contact an Allergy World Clinic near you for further information.