“Medicinal drugs might be an issue to keep an eye on and warn people about, but it’s not the main issue,” he said.

‘NO SUBSTITUTE FOR SLEEP’

One way for people to reduce their accident risk is to take a nap before they hit the road, according to Moore.

“Don’t hesitate if you’re tired to take a short nap or drink a few cups of coffee. And if you drink coffee, it will take some time to take effect,” he said.

Drake added, however, that coffee’s effectiveness can wear off over time.

“Anytime you’re feeling sleepy behind the wheel is a danger sign,” he said.

The standard techniques of turning on the air conditioner or blasting the radio only mask the signs of sleepiness - they don’t make it go away. “They’re good to get you to the next exit, but it’s not going to get you home,” Drake said.

There are some laws in the U.S. to punish sleepy drivers, but Drake told Reuters Health they are hard to enforce unless someone gets into an accident.

“It’s very difficult. There is no breathalyzer for sleepiness,” he said.

The study did have some limitations. Some of the questions are based on the patients’ own reports, which may be subjective. Also, there is no way to know how many accidents sleepiness actually caused.

Overall, Moore said the best advice is, “don’t drink and please sleep.”

“There is no substitute for sleep,” said Drake.

SOURCE: Archives of Internal Medicine, May 2012.

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