Go to Health: Driving Under the Influence Of...


Mothers against Drunk Driving (MADD) has taken on an added cause – drugged driving. According to the National Highway Traffic Safety Administration, one in 8 weekend, nighttime drivers test positive for illicit drugs, and one in 3 drivers killed in auto crashes test positive for drugs. They are referring to illicit and prescription drugs, as well as alcohol. All cause dangers for drivers and their passengers.







The Institute of Medicine has reported that 20% of serious injuries from driving can be attributed to driver sleepiness. Here’s the problem – insomnia is very common, and can of course cause sleepiness and danger at the wheel. However the drugs used to treat insomnia, like Ambien, can also contribute to dangerous driving the next day. An article in the August 22nd New England Journal of Medicine reports on driving impairment in Ambien users. The relationships between drug dose, time of use, and the concomitant use of alcohol or other substances have not yet been completely worked out. However, people using these drugs should know, and should be warned by their doctors, that their driving the next day may be impaired. Studies have shown that they may not be aware of their impairment.







Ambien is the most widely used prescription drug for insomnia. Recent studies have shown that the usual 10 mg dose is too high for women and the elderly, who should start with a 5 mg dose. Because some people can fall asleep easily but wake later and can’t go back to sleep, a lower dose of Ambien, called Intermezzo, has been marketed for midnight wakefulness, to be dissolved under the tongue if the user has at least 4 hours more of sleep-time. Again, the suggested dose is lower for women than men. While the lower doses are more appropriate, daytime hangover is still a problem for many users.




Sonata, Lunesta, and Silenor are other prescription drugs used for insomnia, and may also cause driving impairment the next day, especially in people over 55, according to a French study. All these drugs are also habit forming if used nightly.




Valium and other drugs called benzodiazepines (Ativan, Xanax, Restoril, Halcion, Klonopin) are very useful drugs for anxiety, panic disorder, seizures and other problems. When used for sleep, they can be habit forming and may impair driving the next day.




Marijuana use and its effects on driving have been studied at the University of Washington’s Alcohol and Drug Abuse Institute. Laboratory studies and driving simulator studies have shown a dose-dependent impairment of ability to steer, keep a steady speed, follow another car, reaction time and lane positioning. The combined effects of marijuana and alcohol affect driving even more.




Alcohol, so commonly used, and such a pleasant relaxant for many people, can lead to tragedy behind the wheel. Every day in American, another 27 people die as a result of drunk driving crashes. ‘One for the road’ should be a soft drink or coffee consumed by a designated driver who has remained sober.




Stimulants such as amphetamines, methamphetamine, cocaine, ecstasy, and Ritalin, can make driving extremely unsafe by affecting coordination and attention. Users often drive aggressively and take risks. Drowsiness and rebound fatigue occur when the drug effects wear off. Amphetamines combined with alcohol or opiates are equally dangerous.




Opioid drugs given for pain, such as morphine, codeine, oxycodone and fentanyl patches, can be associated with safe driving in very low doses, but the dangers of road trauma increase with higher doses. People taking these drugs should check with their doctors concerning their driving abilities and safety. When such drugs are taken illegally, often in high doses, the dangers of erratic driving escalate.




Over the counter antihistamines such as Benadryl and Chlor-Trimeton can cause drowsiness and may impair driving abilities.




The average car today weighs 3-4000 pounds. Hurtling along the road at 55 miles per hour or faster, it is both an amazing machine and a dangerous one. We all know people who have been killed or seriously hurt in car crashes. Here’s my take-away from writing this column:




*Never drive under the influence




*Always designate a sober driver at a party




*Suspect all other cars on the road – who knows what the driver has used.




*Pull over for faster drivers and motor cycles




*Respect pedestrians and bicyclists (they may be under the influence too)




*Avoid road rage in yourself and others




*Don’t text, talk on the phone, or take chances




*Give yourself plenty of time to get there so you don’t speed













Sadja Greenwood, MD, MPH. See my column of 4/24/2012 for safe ways to deal with insomnia.