Doctor treats allergies by giving patients what makes them sick

Dallas, TX - (NBC) - Five-year-old Jamesen Harvey is about to eat the food she used to avoid - peanuts.

"If someone were to touch her with peanut hands or kiss her with peanut lips, she would turn red and splotchy and have an allergic reaction," Joy Harvey, Jamesen's Mom, said. "When they brought out they actually brought out the precious little peanut on the tray, I think I had more of a reaction than she did. I was like, what's gonna happen, but it's been so gradual. Each week. We started with tiny, tiny amounts so that by the time we got to one whole peanut and now up to six, it's amazing."

Dallas allergist Richard Wasserman started this food desensitization program 18 months ago. It's a rigorous, risky treatment that can last up to six months.

"We fool the body's allergy and immune system by kinda sneaking up on it. We give very, very teeny doses of the food that causes the problem and gradually increase those over time," Dr. Wasserman said.

10-year-old Cory Feathers is a 4th grader Dr. Wasserman is treating for a milk allergy.

"Even from infant baby formula, he had reactions. So, he's pretty much had to avoid milk all his life," said Cory's mom, Caroline Feathers.

"Now we're up to an ounce and a half. There you go. Hit it," Dr. Wasserman said.

"I don't really worry when we move up a dose, even though, he's getting a significant amount, because we've had so much success," Feathers said.

"For Corey, his end point will be drinking a cup of milk. That's eight ounces," Dr. Wasserman said.

Dr. Wasserman admits there are allergists who think this treatment is too risky, exposes patients to much potential harm. He insists his staff takes extraordinary cautions to keep patients safe. And it is because of his patients, he was willing to try something new.

"This is the most rewarding thing that I've done in medicine in more than 30 years. It really changes people's lives," Dr. Wasserman said.

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