The design of the study didn't allow the researchers to pinpoint exactly how much worse they were, but Rohsenow said the hangovers remained in the mild range even among the smokers. "It's not a whopping effect," she noted.
There's no proof of a cause-and-effect relationship between smoking and worse hangovers. It's possible that something other than smoking -- like, say, the diets of smokers -- could explain the difference, she said.
If smoking while drinking does worsen subsequent hangovers, it may have something to do with the parts of the brain that process both tobacco and alcohol, she said. Or smoking could add to the sleep-depriving effects of drinking too much.
Other research has shown that smoking and drinking together worsen the effects on the brain of alcohol alone, she said.
What should you do if you have a hangover?
According to Rohsenow, doctors recommend drinking plenty of water, taking something to calm your stomach and taking a painkiller such as aspirin or ibuprofen -- but not acetaminophen (Tylenol) -- for a headache. Alcohol may raise the risk of liver damage from acetaminophen.
As for the "hair of the dog" -- downing more booze -- Rohsenow said that hasn't been officially studied. But common sense suggests it's a good idea to stay away from bottles -- not to mention cigarettes -- the day after a night of heavy drinking.
The U.S. National Library of Medicine has details on hangover treatments.
SOURCES: Damaris Rohsenow, Ph.D., research professor and associate director, Center for Alcohol and Addiction Studies, Brown University, Providence, R.I.; January 2013 Journal of Studies on Alcohol and Drugs
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