As students enjoy the spring-like weather by grabbing their Frisbees and baseballs, some students will be grabbing boxes of tissues instead.

According to the American Academy of Allergy, Asthma and Immunology (AAAAI), seasonal allergic rhinitis, or "hay fever," affects more than 35 million people in the United States. Symptoms like a runny nose, sneezing and watery eyes are triggered by allergens such as airborne pollens and mold spores.

The AAAAI advises allergy sufferers to keep their windows closed at night to prevent pollens from entering and to try to stay indoors when the pollen count is particularly high. "More people have general allergies than you would think," said Rebecca Filson (junior-elementary education), who said she has environmental allergies year round, which become worse in the spring because of the amount of allergens in the air and the change in weather.

"Usually it's not bad enough that I can't go to class," she added.

Filson said that she takes prescription medication for her allergies and that it is advisable to take medicine at the first sign of allergic irritation.

There are medications that can be taken for allergies other than antihistamines, which tend to make people drowsy. "There are some nonsedating allergy medicines," said Evan Pattishall, a doctor at University Health Services (UHS), noting that some allergy medicines are tolerated better than others.

Pattishall said a different solution, allergy shots, which can be administered several times, are a more long-term process. The shots have to be tailored to specific allergies, he said. He added that the majority of allergies UHS treats are skin or upper respiratory.

According to the National Allergy Bureau's Pittsburgh pollen-counting station in Allegheny General Hospital, yesterday's tree pollen count was 98 particles per cubic meter, while mold allergens filled the air with 352 particles per cubic meter.

A concentration between 90 and 1,499 particles per cubic meter is considered "high" for tree pollen and a concentration of 1 to 6499 is considered "low" for outdoor mold spores.

The main thing affecting the amount of allergens in the air is the weather, said Brian Beckwith, AccuWeather representative in data acquisition.

How warm it is and the date of the last frost are just two factors that determine the air's allergen count, he said.

The Web site www.pollen.com forecasts pollen levels four days into the future using a formula that incorporates historical trends and forecasted weather. It projects tomorrow's and Saturday's pollen levels to be in its "high" range at 11.6 and 11.0, respectively, on a scale from one to 12.

The pollen-forecast numbers are not based on absolute amounts of pollen in the air but are scaled and put into three categories based on a relative allergy threat: low, moderate and high.