FDA approves medication used to treat asthma for use in people with multiple food allergies

If you have food allergies, you know the dread: You'll be at a gathering and no one can tell you for sure if there are peanuts or eggs in any of the food. So you take a risk or you don't eat.

Now, a medication used to treat asthma can now give people with food allergies some peace of mind.

About 17 million Americans have the type of food allergies that can cause severe anaphylactic shock.

Now Xolair prescribed for allergic asthma flare-ups is FDA approved to prevent severe food allergy reactions in patients as young as one. Xolair is a monoclonal antibody that binds to a specific antibody called IgE which triggers the immune cascade.

"Oh, boy, when you start releasing histamine, you can get flushing and wheezing, and a lot of the signs of, you know, a bad bad reaction happening," said Dr. Raj Dasgupta, a pulmonary critical care and sleep medicine specialist.

In a recent study, 68% of peanut allergy participants tolerated about a half teaspoon of peanut protein compared with 6% of those who received placebo injections.

Doctors measure IgE levels and weight to determine dosage. The drug itself can cause anaphylaxis, but it's a small risk.

"I believe it's zero point one percent. But that's why you want to get the first couple of doses in a healthcare setting. Then they actually have a home injection," he said.

People on the bi-weekly to monthly Xolair stay on it for life. Patients still need to avoid food allergens and continue to carry an epi-pen. Doctors said Xolair is more like an insurance policy against accidental exposure.

"Just because you're on this medication, you still could get anaphylaxis, you still could be exposed, but the chances and the intensity hopefully will be much, much less," Dasgupta said.

The medication is not approved for emergency treatment of allergic reactions. Xolair costs about $2,900 per month for children and $5,000 for adults. Its maker, Genentech/ Novartis, said people with insurance generally pay less.