Allergy Meds Could Affect Your Driving

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If you can literally write your name in pollen on the windshield of your car, you know it’s allergy season again.
When your body comes into contact with whatever triggers your allergy—pollen, ragweed, pet dander, or dust mites, for example—it produces chemicals called histamines. Histamines cause the tissue in your nose to swell (making it feel stuffy), your nose and eyes to run, and your eyes to itch. Some people develop itchy skin rashes known as hives.
Medications containing antihistamines, drugs which counteract the effect of histamines, can help relieve many different types of allergies, including hay fever and food allergies.
But some antihistamines can make you feel drowsy, unfocused and slow to react. If not taken responsibly and according to directions, they can pose a danger to your health and safety. Information about whether an antihistamine medication can make you drowsy can be found in the product’s label. Consumers should read the Drug Facts label of the medication and understand the warnings before they use it.
“Any of these reactions can negatively interfere with driving or operating heavy machinery,” says Jane Filie, M.D., a medical officer at the Food and Drug Administration’s (FDA) Division of Nonprescription Regulation Development. Filie says you may experience slower reaction time, haziness, or mild confusion even if you don’t feel drowsy after taking a medication containing antihistamines.
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Precautions to Take

FDA wants to promote awareness of the potential health risks and the precautions that you should take when using antihistamines.
Different antihistamines may be dosed differently, says FDA pharmacist Ayana Rowley, Pharm.D. “Don’t assume that when you run out of one antihistamine and happen to buy another, it’s the same dose,” she explains. If one specific antihistamine worked for you before, take note of the dosage and make sure you get the same medication the next time.
It’s also important to avoid taking alcohol, sedatives (sleep medications), or tranquilizers while taking some antihistamines. This information can also be found in the Drug Facts label, Filie says. Alcohol and sedatives can seriously increase the sedative effects that already may occur when taking antihistamines.
Rowley also cautions against self-medicating. “If the correct dosage isn’t providing you the relief you expect, don’t simply keep taking more and more of that product,” she says, “but instead, consult your health care professional”.
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Tips to Keep in Mind

Always follow directions for use and read warnings on the packages of the drug products you purchase.
Some antihistamines may cause drowsiness, and you need to exercise caution when driving a motor vehicle or operating machinery. Avoid using alcohol, sedatives, and tranquilizers while taking the product because they may increase drowsiness.
Know that some antihistamines take longer to work than others. Recognize that you might feel the sedating effects of these medications for some time after you’ve taken them and possibly even the next day.

This article appears on FDA's Consumer Updates page, which features the latest on all FDA-regulated products.
May 29, 2013
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