Narcotic painkillers plus sedatives add up to danger behind the wheel
08/27/2013 5:44 AM
08/08/2014 10:18 AM
On a chilly April morning, retired construction worker Philip Smith was driving down a Lake County, Ill., road when police say he sailed through a red light, smashing his Jeep into the side of a school bus.
Most of the 35 children aboard went to the hospital with minor injuries; Smith died at the scene. Authorities tested his blood and determined that the crash had been the result of Smith “having impaired judgment by having multiple drugs in his system.”
What were those drugs? A sedative and a narcotic painkiller, both medications prescribed by Smith’s doctors.
Experts say millions get behind the wheel every day under the influence of powerful medications that, while perfectly legal, can have dangerous consequences on the road.
Narcotic painkillers such as codeine and oxycodone can cause fatigue and mental clouding, while sedatives can slow reflexes. A National Highway Traffic Safety Administration study named a range of other drugs, from antidepressants to beta blockers to allergy pills, as “potentially driver-impairing medications.”
That puts many patients in a difficult dilemma. They’re allowed to drive with these meds in their systems, but there’s no easy way to know the dosage or drug interactions that could make driving unsafe. If they’re pulled over or involved in a crash, a doctor’s order may not save them from being charged with DUI.
Much of the research on prescription drugs and driving has centered on narcotic medications. Scientists have long believed that patients on stable, long-term regimens of opioids – opiumlike painkillers – develop a tolerance that allows them to drive safely, but recent studies have complicated that picture.
One found that high doses of painkillers render a driver more likely to be involved in a crash, a conclusion that prompted a medical journal to editorialize that doctors should “weigh the risk of road trauma into our decisions about the benefits and harms of opioids.”
Another study found that motorists taking the medications are more likely to perform “unsafe driving actions” that make them responsible for roughly 150 fatal crashes in the U.S. each year.
That might not sound like many, considering that more than 200 million opioid painkiller prescriptions are written each year, but research statistician Sacha Dubois said his calculations were conservative: They didn’t include crashes in which people were maimed rather than killed, for instance, or those in which painkillers had been mixed with alcohol.
“This is like a plane crash a year,” he said. “If any company had a plane crash where everybody died, we’d be concerned about it.”
Philip Smith, 62, of Beach Park, had worked in construction until chronic back and neck pain forced him to retire, according to an interview his wife gave to investigators. A few weeks before the fatal crash he slipped and fractured a vertebra, an injury that put him in a back brace.
Smith had been on “multiple pain management medications for many years” under the care of a Lincolnshire specialist, his wife said, and was taking daily doses of morphine and diazepam, the generic version of Valium.
Jerrold Leikin, director of medical toxicology at NorthShore University HealthSystem, reviewed Smith’s toxicology report at the Chicago Tribune’s request and said the results were “compatible with impairment.”
Smith’s wife declined interview requests from the Tribune. She has filed a lawsuit against the bus company, Durham School Services, claiming it was actually the bus driver who ran the red light.
James Zacny, a University of Chicago anesthesiology professor who has studied the effects of opioid painkillers on driving, said those drugs, when used alone at an appropriate dose, can actually improve motorists’ performance by allowing them to focus on the road instead of their pain.
The problem comes when opioids are combined with other drugs, such as sedatives, he said. The interaction’s effect on driving has not been well-researched, but Zacny said it would likely cause problems.
“It’s a synergistic effect, like one plus one equals three,” he said. “It’s a stronger effect than if you doubled the dose of the opioid.”
Some doctors are cautious even when drug interactions are not an issue. Lynn Webster, a Salt Lake City physician who is president of the American Academy of Pain Medicine, said he advises patients taking narcotic painkillers to stay off the road unless they can prove they’re not impaired with a session in a driving simulator.
He acknowledged, though, that it’s just a recommendation – patients do not need their doctor’s permission to drive.
“It’s often a trade-off for patients,” he said. “They have to assume the risk of driving, but I think most physicians would advise them not to.”