What causes allergies to develop and how do they impact the body?

Allergies happen when your body thinks something harmless is actually dangerous, and it goes on a big, noisy defense mission.

Imagine you're playing in the park, and suddenly a friend throws a bunch of confetti into the air. Your eyes start to water, and your nose starts running. That's like an allergy: your body sees the confetti (which is like allergens, like pollen or pet dander) and thinks it’s a big attack.

Your immune system, which is like your body's superhero team, gets excited and says, "Hey! I’ve seen that before!" So it sends out tiny soldiers called white blood cells to fight off the confetti. That’s why you get sneezing, itching, or even a runny nose.

Sometimes, if your body fights too hard, it can make you feel like you're stuck in a big, messy game, you might have trouble breathing, or your skin might get all itchy and red.

But don’t worry, just like you learn to play better with confetti over time, your body can also learn to be less surprised by the allergens.

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Examples

  1. A child sneezes and itches after eating peanuts for the first time.
  2. Someone gets a runny nose when they walk outside on a windy day.
  3. A person breaks out in hives after touching a new fabric.

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