(HealthDay News) -- As if migraine sufferers didn't already have enough pain, new research has found that they may also be more prone to hangover headaches.

U.S. researchers studied the effects of alcohol on a group of rats that experience recurrent migraines as well as a group of control rats that don't get the headaches. The study authors found that the rats with migraines experienced more pain four to six hours after ingesting alcohol than the control rats.

"Our results suggest that dehydration or impurities in alcohol are not responsible for hangover headache," Michael Oshinsky, an assistant professor of neurology at Jefferson Medical College of Thomas Jefferson University, and a member of the Jefferson Headache Center team, said in a university news release.

"Since these rats were sufficiently hydrated and the alcohol they received contained no impurities, the alcohol itself or a metabolite must be causing the hangover-like headache. These data confirm the clinical observation that people with migraine are more susceptible to alcohol-induced headaches," Oshinsky added.

The study was scheduled to be presented at the annual meeting of the Society for Neuroscience, held Oct. 17 to 21 in Chicago.

The researchers are now studying the mechanism for causing a headache, along with the metabolites of alcohol that trigger hangover headaches.

More information

The U.S. National Institute of Neurological Disorders and Stroke has more about migraine.
http://www.ninds.nih.gov/disorders/migraine/migraine.htm