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Allergies Health Center

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Adult-Onset Allergies

How Common Are They? continued...

Whatever the case, allergies are all over, and they’re big business. They’re the sixth-leading cause of chronic illness in the U.S., according to the CDC. And they cost Americans more than $18 billion a year.

We know what causes allergies: Your immune system overreacts to an allergen (like your dog or a shrimp cocktail). You sneeze, sniffle, itch, or cough. But why this happens to you, when your Uncle Fred is on his third shrimp cocktail, is unclear.

Allergies that pop up for the first time in adults are even more mysterious. Why is it that when you were a kid, your best buddy was your cat Muffinmitts, but now the fur ball next door makes your eyes itch so bad you want to claw them out?

“That’s the thing about allergies,” Corn says. “You’re fine, you’re fine, you’re fine ... until you’re not.”

Nobody knows why.

“Most people are exposed to most of the [allergens] over their entire life,” McGrath says. “So why does it suddenly turn on? If we understood exactly what turned it on, we could probably turn it off. That would be the holy grail of allergy.”

For now, we’ve got to learn to manage allergy symptoms. The rules are the same for adults as they are for kids:

  • Avoid the allergens, if you can
  • Take allergy medicines
  • Consider allergy shots (immunotherapy)

Both McGrath and Corn say they see plenty of adults who are shocked to learn that the cough they’ve developed isn’t due to a cold, but an allergy.

“They’re a little surprised, but I think for the most part they’re happy. Because now they have a reason for why they’re feeling the way that they feel,” Corn says. “When you’re older, you realize that in the spectrum of things that you can have … if all you’re getting is allergies, then you’re really happy with that.”

A Shot of Hope

Allergies can sneak up on you. That cough may not be just a tickle, but a nasal drip because of an allergy, Corn says. That dead-tired feeling you have might not be you getting older. It may be an allergen that’s keeping you from getting a good night’s sleep.

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