February 2013

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Health Capsule

Therapy Shows Promise for Peanut Allergy

An experimental therapy may one day make life easier for people with peanut allergy, who now need to avoid all foods containing peanuts.

Food allergies are caused by your immune systemThe system that protects your body from harmful microbes., which normally protects your body from harmful germs. When you’re allergic, the immune system responds to a harmless substance as if it were a threat. Symptoms can range from hives and itching to a life-threatening reaction called anaphylaxis.

Peanuts are one of the most common foods to cause allergic reactions in both children and adults. The only way to prevent symptoms is to completely avoid peanuts and all products made with them. But that’s not easy to do.

An NIH-funded research team tested an approach called sublingual immunotherapy to treat peanut allergy. The therapy involves placing a small amount of liquid under the tongue and then swallowing it.

The researchers enrolled 40 people (ages 12 to 37) who had peanut allergy. They were randomly assigned to receive either sublingual immunotherapy or an inactive placebo.

After 44 weeks, 14 of the 20 treated patients (70%) could safely swallow at least 10 times more peanut powder than they could at the start of the study. Only 3 of the 20 (15%) taking placebo could similarly increase their dose safely. After 68 weeks of therapy, patients could swallow even more peanut powder.

“Immunotherapy continues to show promise for treating food allergies, but it is not yet ready for widespread use,” says study co-leader Dr. David Fleischer of National Jewish Health in Denver. “This is an experimental treatment—promising, but with potentially serious side effects.” The researchers are now working to improve the technique.

Several other trials are testing oral immunotherapy for food allergy. But if you’re allergic, don’t try any type of immunotherapy on your own. You could have a dangerous reaction.