Cup of Coffee Doesn’t Dispel Liquor’s Effect

Making that “one for the road” a steaming cup of coffee to dispel the effects of alcohol doesn’t work, warns a specialist at New York University Medical Center. In fact, driving under the dual influence may be even more dangerous.

“Remember caffeine is also a mind-affecting drug,” cautions Dr. Robert A. Maslansky, instructor in clinical medicine and director of the substance-abuse program at Bellevue Hospital Center. “And it can be quite deceptive.”

Caffeine’s effect is to speed and heighten reactions, he notes. “We don’t have exact words to describe fully the ways in which drugs affect the mind. But the poet Robert Lowell once described the state of mania as ‘irritable enthusiasm.’ That is a good capsule characterization of the effect of caffeine: putting an ‘edge’ on responses, subjectively countering the dulled state of having had a few drinks.”

But that effect is strictly subjective. While caffeine will probably make you move faster, it will not enable you to move more skillfully. Caffeine may improve performance of a simple, routine task, but not such a complex one as operating a motor vehicle. And it does not cancel out alcohol’s effects.

“Alcohol,” Maslansky points out, “impairs motor skills. It impairs judgment. It impairs such key visual abilities as dark-adaptation, for example, the ability to readjust after passing a pair of high-beam headlights. No matter how capable and alert one may feel, as long as the alcohol remains in the bloodstream, caffeine will not counter these impairments.”

Further, he observes, a second effect of a stimulant such as caffeine is to increase both self-confidence and aggression. When these are coupled with alcohol’s effects, “the result may well be even more destructive behavior. Behind the wheel of a car, that can add up to disaster.”