Exercise can trigger life-threatening allergies

LOS ANGELES (KABC) -- A solitary jog is a luxury for marathon racer Mayra Suarez, because her doctor warned her never to run alone. The last time she did, it nearly killed her.

"I was having a really hard time breathing. My lungs, my airways were starting to close up. My eyelids were pretty swollen. I started running around looking for some antihistamine," Suarez said.

"Before I knew it, I had actually collapsed. I fell back, hit my head. They had to call the paramedics," said Suarez, who was taken to the emergency room.

The 34 year old, who works for Kaiser Permanente, was in anaphylactic shock. The cause? Exercise!

Her doctor, Dr. Shafali Samant, an immunologist at Kaiser Permanente Los Angeles Medical Center, says in some people strenuous activity triggers a life-threatening allergic reaction.

"There's some thoughts that maybe active exercising releases hormones within the body, which produces chemicals that cause anaphylaxis," Samant said.

Many people with exercise-induced allergies don't know they have it or think it's something else. Previous research shows that exercise-induced allergies are responsible for 5 to 15 percent of anaphylactic shock cases.

"The episodes are not that frequent," Samant said. "It may happen once a year, twice a year."

In some, it may not be exercise alone. Certain foods like wheat, nuts or grains combined with activity leads to the lethal combination.

"They're able to exercise okay. They're able to eat the food okay. But when they put the two together is when they have the issue," Samant said.

In Suarez's case, Samant could not find a food association. Still, she's advised Suarez not to eat four hours prior to exercise and to carry an EpiPen at all times.

Despite the risk, Mayra wants to continue running marathons.

"It's something I enjoy and something that I know is good and healthy for me," Suarez said. "God willing as long as I can do this, I'm going to keep running."