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Distracted driving has gained attention recently with increasing concerns about the risks associated with cellphone use and other multitasking behaviours behind the wheel. And drunk driving has been on our radar for decades now. This article is about another dangerous driving condition, one that is frequently ignored or minimized by drivers: drowsiness.

According to the Washington, D.C.-based Foundation for Traffic Safety, 21 per cent of fatal U.S. car crashes involve drivers who are drowsy – driving while sleepy or falling asleep at the wheel. Horrific accidents illustrate potential consequences of driving while sleepy. Last year, two separate coroner's reports, one from B.C. and the other from Quebec, concluded that drowsy driving was the likely cause of a 2010 ambulance crash on Vancouver Island that killed two paramedics and a 2011 van and school bus collision that killed five farm workers in the Lanaudière region.

While drowsy driving is dangerous at any age, drivers under age 25 top the statistics for sleep-related crashes. Young drivers are more likely to be deprived of sleep when they go on long road trips. A tendency to overestimate their driving ability and to continue to drive when sleepy puts them at elevated risk of crashing.

Researchers of drowsy driving, including Dr. Alistair MacLean of Queen's University Department of Psychology, have shown that young adults who've been awake for 18 1/2 hours make driving errors that are similar to someone with a .05 blood alcohol concentration. Being awake for 21 hours, they say, produces errors similar to .08 BAC. Like drunk drivers, sleep-deprived drivers make erratic speed and lane changes, have slowed reaction times and an increased tendency to drive off the road.

Despite the similarities in the effects of sleep loss and alcohol on driving performance, other research from MacLean's lab (which I was involved in, published in the Journal of Safety Research) found that young drivers viewed sleepy driving as fairly normal and "understandable," whereas they viewed drunk driving as definitely wrong.

Drowsy driving needs to be recognized as equally dangerous as drunk driving.

A few campaigns are under way to draw attention to drowsy driving. The U.S.-based National Sleep Foundation initiated a National Drowsy Driving Awareness Week, and some European countries and a few Canadian jurisdictions post road signs saying "Drowsy Driving Causes Crashes" or "Drowsy Drivers Next Exit 5 km."

More public education is needed to raise awareness.

How can you reduce your risk? Before taking that road trip, think carefully about your plans. Following the guidelines below will reduce the likelihood of falling asleep at the wheel and increase the chances of a safe trip.

• Make sure you are well rested before driving. Ideally, you've had a solid seven or more hours of sleep. It is worthwhile postponing driving until you are well rested. Stay overnight rather than pushing ahead on the road.

• Don't ignore the symptoms of sleepiness – yawning, trouble focusing, difficulty keeping your eyes open, difficulty remembering the last few kilometres, drifting outside your lane, willing yourself to stay awake.

• If you experience sleepiness while driving, find a safe place to pull off the road. Take a 15- to 20-minute nap. This is the best intervention. Rolling down the window to get fresh air, turning on the air-conditioning or turning up the music are ineffective.

• A cup of coffee may be somewhat helpful, but it will take 20 to 30 minutes to have an effect. So rather than drinking it on the road, drink it during an off-the-road rest period.

• Schedule a break at least every two hours or 200 kilometres.

• Drive only during times when you are normally awake. Especially, do not drive during the time of greatest danger for sleep-related crashes: 2 a.m. to 5 a.m.

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Dr. Judith R. Davidson is a clinical psychologist and sleep researcher. She works with the Kingston Family Health Team and Queen's University, and is the author of Sink into Sleep: A Step-by-Step Workbook for Reversing Insomnia. Follow her on Facebook and on Twitter at @JudithRDavidson

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