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Seasonal Allergies (Hay Fever)

About Seasonal Allergies

"Ah-choo!" It's your son's third sneezing fit of the morning, and as you hand him another tissue you wonder if these cold-like symptoms — the sneezing, congestion, and runny nose — have something to do with the recent weather change. If he gets similar symptoms at the same time every year, you're likely right: seasonal allergies are at work.

Seasonal allergies, sometimes called "hay fever" or seasonal allergic rhinitis, are allergy symptoms that occur during certain times of the year, usually when outdoor molds release their spores, and trees, grasses, and weeds release tiny pollen particles into the air to fertilize other plants.

The immune systems of people who are allergic to mold spores or pollen treat these particles (called allergens) as invaders and release chemicals, including histamine, into the bloodstream to defend against them. It's the release of these chemicals that causes allergy symptoms.

Seasonal Allergies sidebar

People can be allergic to one or more types of pollen or mold. The type someone is allergic to determines when symptoms occur. For example, in the mid-Atlantic states, tree pollination is February through May, grass pollen runs from May through June, and weed pollen is from August through October — so kids with these allergies are likely to have increased symptoms at those times. Mold spores tend to peak midsummer through the fall, depending on location.

Even kids who have never had seasonal allergies in years past can develop them. Seasonal allergies can start at almost any time, though they usually develop by 10 years of age and reach their peak in the early twenties, with symptoms often disappearing later in adulthood.

Signs and Symptoms

If your child develops a "cold" at the same time every year, seasonal allergies might be to blame. Allergy symptoms, which usually come on suddenly and last as long as a person is exposed to a particular allergen, can include:

  • sneezing
  • itchy nose and/or throat
  • nasal congestion
  • clear, runny nose
  • coughing

These symptoms often come with itchy, watery, and/or red eyes, which is called allergic conjunctivitis. If your child has wheezing and shortness of breath in addition to these symptoms, the allergy may have progressed into asthma.


Seasonal allergies are fairly easy to identify because the pattern of symptoms returns from year to year following exposure to an allergen.

Talk with your doctor if you think your child might have allergies. The doctor will ask about symptoms and when they appear and, based on the answers and a physical exam, should be able to make a diagnosis. If not, the doctor may refer you to an allergist for blood or allergy skin tests.

To determine an allergy's cause, allergists usually do skin tests in one of two ways:

  1. A drop of a purified liquid form of the allergen is dropped onto the skin and the area is pricked with a small pricking device.
  2. A small amount of allergen is injected just under the skin. This test stings a little but isn't extremely painful. After about 15 minutes, if a lump surrounded by a reddish area appears (like a mosquito bite) at the injection site, the test is positive.

Even if a skin test or a blood test shows an allergy, a child must also have symptoms to be definitively diagnosed with an allergy. For example, a child who has a positive test for grass pollen and sneezes frequently while playing in the grass would be considered allergic to grass pollen.



Have your child wash hands or shower and change clothing after playing outside. And a child with seasonal allergies should not mow the lawn (this tends to kick up pollen and mold spores).

If reducing exposure isn't possible or is ineffective, medicines can help ease allergy symptoms. These may include decongestants, antihistamines, and nasal spray steroids. If symptoms cannot be managed with medicines, the doctor may recommend taking your child to an allergist or immunologist for regular allergy shots (immunotherapy), which can help desensitize kids to allergens.

Reviewed by: Nicole A. Green, MD
Date reviewed: May 2013