Kids May 'Learn' to Tolerate Food Allergens

July 6 -- SUNDAY, July 5 (HealthDay News) -- Doctors have long used allergy shots to desensitize children and adults to environmental allergens such as bee stings, pollen, mold and dust mites.

Now researchers are trying to apply that theory to food allergies, through processes called oral immunotherapy and sublingual immunotherapy.

They believe they can build up a child's tolerance for a food that prompts an allergic reaction by exposing the child to tiny amounts of that food.

"It is something that has been recently put into play," said Dr. Michael Pistiner, an allergist in Leominster, Mass., and a spokesman for the American Academy of Allergy, Asthma & Immunology. "More and more of these trials have been started. It does seem to be very promising. It's very exciting."

Trials involving eggs, peanuts and milk have produced positive results, said Dr. Scott H. Sicherer, an associate professor of pediatrics at the Jaffe Food Allergy Institute at the Mount Sinai School of Medicine and chairman of the allergy and immunology section for the American Academy of Pediatrics.

"The studies are promising in that some individuals are able to get to high doses of the food used in treatment," Sicherer said.

Sublingual immunotherapy works by placing an extract of the food allergen under the child's tongue. The membranes of the mouth absorb trace amounts of the allergen, absorbing just enough to desensitize the immune system without prompting an allergic reaction.

Oral immunotherapy takes it a step further by having children eat tiny amounts of the allergen. "The approach involves ingesting an extremely small and then gradually increasing amount of the food under medical supervision, with the hope of getting to an amount that is not causing reactions and is more substantial in dose," Sicherer said.

However, both Sicherer and Pistiner warn that these therapies are still in the experimental stage, and many questions remain.