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Quick Facts

Seasonal Allergy


The Manual's Editorial Staff

Last full review/revision Jan 2021| Content last modified Jan 2021
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What are seasonal allergies?

An allergy is when your body's immune system reacts to something harmless, such as food, plants, or medicine. Seasonal allergies are allergies that happen only during the time of year when a certain substance you're allergic to (allergen) is in the air. Seasonal allergies are sometimes called “hay fever.” Grass, pollen, or mold are common allergens that cause seasonal allergies.

Seasonal allergies can happen in the spring, summer, or fall, depending on what you're allergic to.

  • Seasonal allergies are your body’s reaction to pollen, grass, or mold in the air

  • Usually they cause a runny, itchy nose and itchy eyes

  • Medicine can help with your symptoms

What causes seasonal allergies?

Seasonal allergies are often caused by:

  • Pollens

  • Grasses and weeds

  • Mold spores

The amount and type of pollens, grasses, and other allergens in the air changes depending on where you live.

What are the symptoms of seasonal allergies?

  • Itchy, red, watery eyes

  • Runny or stuffy nose

  • Sneezing

Your symptoms come and go depending on the season.

How can my doctor tell if I have seasonal allergies?

Your doctor can tell if you have seasonal allergies by asking questions about your symptoms and whether they happen during certain seasons. This can also help doctors tell which allergen causes your symptoms.

Skin tests can help doctors know which allergen is causing your allergy.

How do doctors treat symptoms from seasonal allergies?

Your doctor will have you treat your allergies with:

  • Corticosteroid nose sprays

  • Antihistamines

  • Decongestants

  • Eye drops

If these medicines don't help and your symptoms are severe, your doctor may recommend you get:

  • Allergy shots (desensitization)

In desensitization, the doctor gives you shots of the substance you're allergic to. At first the shots have only a very, very tiny amount of the substance. The amount is too small to cause a severe reaction. Then the doctor gives you shots that have more and more of the substance. That way, your body can become used to the substance and not have an allergic reaction. Allergy shots don't always work. And when they do work, you may have to keep getting the shots.

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