A team from the University of Texas in Houston has found that a measure of alcohol followed by a cup of coffee may work just as well to limit stroke damage.

When strokes were induced in laboratory rats, the alcohol and caffeine combination was found to protect their brains.

But the researchers stressed that more tests were needed before the benefits could be estimated for human beings.

However, they said their findings also showed that drug companies may not necessarily be the only places to look to for new therapies.

Dr James Grotta, a neurologist who led the study, said: "Obviously no pharmaceutical company is going to fund a study of alcohol and caffeine since they won't be able to make money from those substances."

Dr Grotta and his colleagues presented their findings to a meeting of the American Neurological Association in Seattle.

Caffeine affects brain chemicals

Coffee beans: caffeine affects brain chemicals

Statistics show that people who regularly drink modest amounts of alcohol have a lower risk of dying from heart disease and stroke, while caffeine is known to affect certain brain chemicals involved in stroke.

The researchers induced ischemic strokes - caused when a blood clot blocks blood flow - in the rats and then gave them various substances to see what would happen.

Currently stroke treatments such as the drug tPA can limit the number of cells that die after an ischemic stroke, but only if they are given within a few hours.

Alcohol alone made the stroke worse. Caffeine alone had no discernible effect. But the two together protected the brain.

Dr Grotta said: "We found that if we gave a combination of alcohol and caffeine, equivalent to, say, one drink of alcohol and two or three cups of coffee, that there's almost complete protection from a stroke.

"The striking thing to me isn't just that it's effective but how great the effect is. It really is very dramatic."

However, Dr Grotta warned against any attempt by patients to self-medicate.

He said: "If you give too much of either the alcohol or the caffeine, then the effect is lost."

Caution needed

Professor Kennedy Lees, a stroke specialist at the Western Infirmary in Glasgow, said the research was "intriguing" but should be treated with great caution.

He said any attempt to give patients alcohol and caffeine to drink would be fraught with difficulty as one of the most common effects of stroke was difficulty in swallowing.

Professor Lees said many other chemicals had been successfully tested on rats, but had subsequently failed to show any positive effect on humans.

He said: "The last thing we want to see is stroke patients coming into hospital drunk on alcohol and drugged up on caffeine with all the potential complications that could cause."

Professor Lees said clinicial trials were currently taking place to test the impact on stroke of doubling the amount of magnesium in the body.