Year-round allergies make ragweed season worse

Michelle Jason suffers from year-round allergies, both indoors and outside.

"I'm allergic to a lot of things, almost everything – indoor, outdoor, mold, dust, everything outside, grass, trees, wool, milk," she said.

When making the rounds as a real estate agent, Jason said, she can tell immediately if there's a cat in a residence.

"If I'm hosting an open house, I'll put the cat in the bathroom and shut the door," she said. "I have no choice. I like cats, but I can't sit in the middle of an apartment sneezing while people walk in and out."

New research shows that Jason's indoors allergies can make her outdoor allergies even worse – especially toward the end of summer when pollen-filled ragweed thrives across the country.

Ragweed refers to 15 different types of plants in the sunflower family. It grows throughout the United States in August and September.

"Individuals that had year-round or perennial allergies to these indoors allergens, when ragweed season hit, they had more sudden symptoms," said Dr. Cliff Basset, with the American College of Allergy, Asthma and Immunology.

Researchers found that the immune system of people with year-round allergies is hypersensitive because it always dealing with their symptoms. When ragweed season comes along, their immune system is primed to, in effect, over-react.

Doctors said that patients who don't treat their allergies year-round suffer the most.

"Those the patients that seem to be much more symptomatic during allergy season, and even medications don't work as well on these individuals," Bassett said.

Jason said that she gets an allergy shot every week throughout the year.

"You do what you have to do. You take medication and carry on," she said.