March 16 (Bloomberg) -- The sneezing, wheezing and sinus congestion of allergies can affect children's sleep, as well as their ability to compete in sports and concentrate in school, according to a survey involving more than 1,000 families.

Twice as many parents of children with allergies as those without the condition said it limited their child's activities in research to be reported tomorrow at the American Academy of Allergy, Asthma and Immunology meeting in Philadelphia. Almost half of parents surveyed said their children use prescription medicine to treat their allergies.

Allergic rhinitis affects about 40 million people in the U.S., including up to 40 percent of children, according to the researchers. The condition is most severe in the spring when plant and tree flowers fill the air with pollens that trigger immune responses. Severe allergies can lead to asthma, chronic sinus problems or ear infections, researchers said.

``Allergies are more than just a sneezing nose, running nose or itching. They have a major effect on children,'' said study author Michael Blaiss, a Memphis, Tennessee, allergist who is a past president of the allergy group, in a March 14 phone interview. ``One has to realize that allergic rhinitis is not a trivial condition. We see marked impairment in children.''

Allergies can be seasonal, such as those caused by pollens, or perennial, which is triggered by pet dander or dust and can cause more persistent and chronic symptoms.

Researchers surveyed 500 parents of children aged four to 17 who were diagnosed with and receiving treatment for allergic rhinitis. They also surveyed 504 parents of children without the condition.

In the study, 40 percent of parents said that allergies interfere with their child's sleep versus 8 percent of parents of children without allergies who said health affected sleep,

The study was funded by Sepracor Inc., which sells the Omnaris nasal spray that is used to treat seasonal allergies.

To contact the reporter on this story: Nicole Ostrow in New York at nostrow1@bloomberg.net.

Last Updated: March 16, 2008 12:33 EDT