Here are other facts about hay fever, including suggestions to reduce symptoms, courtesy of the American Lung Association:

• Symptoms often include congestion, red and watery eyes, sneezing, runny nose, and itchy eyes and ears.
• Many people who have hay fever develop asthma.
• Hay fever is more common during certain times of the year in different regions, depending on seasonal pollen counts in those areas.
• Symptoms may be reduced by limiting exposure to the outdoors. Use air conditioning and air-purifying devices, stay inside, and wear a dust mask if you have to be outside.
• Antihistamines and decongestant medications can help control symptoms.

Free asthma screenings are scheduled to be held at 250 locations across the United States as part of National Asthma and Allergy Awareness Month. The American College of Allergy, Asthma & Immunology sponsors the annual effort, and this year the emphasis is on helping those already diagnosed with asthma to get it under control as best they can.

In recent months, the National Heart, Lung, and Blood Institute (NHLBI) put out new guidelines highlighting the importance of asthma control, including daily monitoring and proper medication use to treat symptoms and prevent severe attacks from occurring. This came in light of research showing that many people with asthma are suffering more than they need to from the disease.

"The government guidelines emphasize that undiagnosed or inadequately treated asthma worsens the severity of the disease," allergist John Winder, chairman of the Nationwide Asthma Screening Program, said in a prepared statement. "The screening program gives patients who are still having breathing problems a chance to meet with an allergist, discuss their symptoms and learn how to feel better."

More than 22 million Americans, including 6.5 million children, have asthma -- a chronic inflammation of the airways in the lungs. Asthma attacks, which claim nearly 4,000 lives a year, are often triggered by allergens -- these include pollen, dust, animal dander, certain drugs and food additives -- lung infections, or even physical exertion. While the disease's exact cause remains unknown, many treatments are available to keep it in check.

"An asthma 'attack' isn't the only sign of trouble. A cough that bothers you at night, shortness of breath, colds that go to your chest -- these can all be symptoms of asthma. But few people recognize them or that they are a sign of under-treated disease," Winder said. "No one with asthma should have to suffer. Anyone who is experiencing breathing problems or making compromises to live with their condition should attend a free screening and find out how to take control."

The screenings will be overseen by allergists, who are asthma specialists, and done in coordination with local doctors and allied health professionals. During a screening, participants will answer several questions about their breathing issues, take a lung function test that involves blowing into a tube, and meet with an allergist to determine whether a more thorough exam and diagnosis is needed.

The program has screened more than 108,000 people over the years, and more than half of those were referred for further diagnosis.

A list of free asthma screening locations and dates, online versions of the breathing questionnaires, and more information on treating and controlling asthma are on the ACAAI Web site at www.acaai.org.

More information

The National Heart, Lung, and Blood Institute has more information about controlling and treating asthma.

However, this can be an extremely bad idea, experts say. Prescription drugs, after all, are prescribed for a reason: Because a doctor or pharmacist needs to play a role in their use.

In the case of shared antibiotics, "we've managed to document that this is a real public health risk," said study author Richard Goldsworthy, CEO and director of research and development for The Academic Edge company in Bloomington, Ind.

Goldsworthy's company came up with the idea for their survey while studying whether prescription warning labels should urge some users to not share their medication. Would the labels be effective?

"There wasn't a whole lot of data on it," Goldsworthy said. "So we decided if we were going to ask the question, we needed to look more broadly at the entire issue, find out who's sharing."

In 2006, researchers interviewed 700 people aged 12 to 44 in several large U.S. cities, including Los Angeles, Phoenix, Philadelphia and Atlanta, among others. In the one-on-one interviews, the researchers asked the subjects about their use of medications.

The findings are published in the June issue of the American Journal of Public Health.

Two-thirds of those surveyed said they had never borrowed medications from others or shared their own. However, 23 percent said they'd shared their medications with others, and 27 percent had borrowed them; 16 percent had done both.

About 22 percent reported shared pain medications, and 7 percent said they'd shared mood-altering medications. A quarter said they'd shared allergy medications, and almost 21 percent reported sharing antibiotics.

The latter number is worrisome, because patients shouldn't have any antibiotics left over after a prescribed course of treatment, Goldsworthy said. In addition, he said, overuse of antibiotics is contributing to the rise of germs that are immune to many drugs.

"Don't share antibiotics," Goldsworthy advised. "You shouldn't have any leftover. You should have finished them all yourself."

In some cases, however, sharing drugs may not be very risky, Goldsworthy said, and is done for "pretty reasonable reasons."

"I happen to share some painkillers, because I have a bad toothache, I'm sneezing, and my mother-in-law has a prescription medicine while we're on a trip," he explained.

In general, he said," people share for a variety of reasons. They share because it's convenient, because they want to fix a problem. And they share for thrill-seeking, like when they get pain and mood-altering medications."

Should prescription medications come with warning labels telling users to not share them? Goldsworthy isn't sure, especially considering that medications already have plenty of warning labels. "It would just get loss in the sea of other ubiquitous messaging that ends up on pharmaceutical packaging," he said.

More information

The FDA has details about using medicine properly.

Traditional latex gloves are made from the sap of a rubber tree. The sap contains a protein that may trigger allergic reactions, especially among people who use the gloves repeatedly over long periods. Mild reactions may include rash, hives, skin redness and itchiness, while more serious problems could include difficulty breathing and wheezing, the FDA said.

The agency cited estimates that 3 percent to 22 percent of health-care workers are "sensitized" and may react to traditional latex.

The newly approved Yulex gloves are made of latex from a guayule bush, native to the Southwestern United States. Studies indicate that even people who are highly allergic to traditional latex do not react on first exposure to the Yulex gloves, the FDA said.

The product is made by the Yulex Corp., of Maricopa, Ariz.

More information

The National Library of Medicine's Medline Plus product has more about latex allergy.

"Gardening outside during times of high pollen counts puts patients at risk for severe allergic symptoms," Dr. Warren Filley, an allergist/immunologist in Oklahoma City, said in a prepared statement.

"Avoidance measures, as well as the use of medications and allergy immunotherapy, can make the difference between having fun in the garden and being miserable," said Filley, a long-time gardener who suffers from allergies.

An allergist/immunologist can help determine which plant species are causing allergies and offer advice on the best time of day or season to work in the garden, according to the American Academy of Allergy, Asthma & Immunology (AAAAI). For example, pollen levels are typically lower on rainy, cloudy and windless days.

Gardeners can also control their allergies by careful selection of plants. Certain flowers, trees and grasses are less likely to produce pollen. These include: cacti, cherry, dahlia, daisy, geranium, iris, magnolia, rose, snapdragon and tulip.

Plants that are highly allergenic include: ash, cedar, cottonwood, oak, maple, pine, saltgrass and timothy.

Skin testing is the best way to determine which plants will trigger allergic reactions in individuals, said the AAAAI, which offered some additional allergy prevention tips for gardeners:

• Whenever working around plants likely to cause an allergic reaction, avoid touching your eyes or face.
• Consider wearing a mask to reduce the amount of pollen spores that you inhale.
• Wear gloves, long-sleeved shirts and long pants to minimize skin contact with allergens.
• Leave gardening tools and clothing, such as gloves and shoes, outside to avoid bringing allergens indoors.
• Shower immediately after gardening or doing other yard work.

More information

The American Academy of Family Physicians has more about allergies.