(WASHINGTON) -- They may seem like harmless over-the-counter medications, but everyday drugs like pain relievers or cough suppressants can impair a pilot's ability to safely fly a plane or helicopter, according to a new study by the Federal Aviation Administration and the general aviation industry.
According to the study, medications played a role in 12 percent of fatal general aviation crashes in the past decade.
Concerned, the industry and government on Wednesday sent out an alert to the nation's estimated 450,000 general aviation pilots to warn them to pay careful attention to any medications they may be taking.
The letter points out that "pilots might not be aware of the ubiquitous presence of sedating antihistamines in many over-the-counter treatments for common allergies, coughs, colds and sleep aids." It urges pilots to pay careful attention to side-effects of any medication, and recommends that pilots wait as long as five times past the dosing interval before climbing into a cockpit.
"So if it was an eight-hour medication, you might go as long as 40 hours before you get into an aircraft," said Bruce Landsberg, president of the Aircraft Owners and Pilots Association (AOPA) Foundation.
"It's important for pilots to understand that any medication that they take may have some kind of effect," he said.
One accident cited in the letter to pilots killed 3- and 6-year-old girls and their grandparents. The grandfather was at the controls when the small plane went down short of the runway in Visalia, Calif., in 2006. The National Transportation Safety Board found that one of the causes of the crash was a build-up of sedating medication -- an over-the-counter sleep aid -- in the man's system.
Commercial pilots are required to do a blood test at least once a year for their physicals to check for any medications. There's no such requirement for general aviation pilots.
In a statement, the FAA said it "believes education pilots to make themselves aware of the potential detrimental effects of medications is the most effective way to address this issue."
In an FAA brochure entitled "Medications and Flying," the FAA tells pilots they should not fly while using any medication whose side effects include "lightheadedness, dizziness, drowsiness or visual disturbance."
Of course, any warning against "operating motor vehicles or machinery" while on the medication is also a red flag.
The FAA's own study of fatal accidents between 2004 and 2005 found that drugs and medications were found in 42 percent of pilots who died in plane crashes. That report did not indicate whether the substances contributed to the accidents, but did underscore the widespread use of medications.
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