Drug may help alcoholics cut down

The Scripps Research Institute and the Eli Lilly drug company study also found the chemical could prevent relapses and reduce the effects of hangovers.

The animal study in the Journal of Neuroscience used a synthetic compound to block a chemical response in the brain which triggers relapse.

Alcohol related deaths have doubled in the UK since 1991.

Stress

The compound, called MTIP, blocks the action of the brain chemical corticotropin-releasing factor (CRF).

ALCOHOL FACTS

• UK alcohol-related deaths rose from 4,144 in 1991 to 8,386 in 2005
• In 2005, 19% of men were classed as 'heavy' drinkers - drinking over eight units a day
• In the same year, 8% of women were heavy drinkers - having more than six units a day
• Liver disease is the fifth highest cause of death in the UK
• Source: Office for National Statistics

CRF levels in the brain rise in the short term after drinking, but normally return to normal within a day or so.

The study found the CRF system becomes overactive in animals with a long term history of alcohol dependence, increasing the risk of relapse.

The researchers used MTIP to block CRF activity in stressful situations, but found it had no affect on CRF activity under ordinary circumstances.

They looked at rats who had been put through several cycles of heavy alcohol consumption and withdrawal to create dependency, as well as animals selectively bred to consume more alcohol.

Injections of MTIP stopped both groups of animals consuming excessive amounts of alcohol and eliminated their susceptibility to relapse when they were stressed.

Human potential

However the compound did not affect the animals' natural curiosity, or lower levels of alcohol consumption in rats that were not alcohol-dependent.

"It moves the field closer to the day when the dark side of addiction is treated"
Dr George Koob, Scripps Research Institute

The researchers say MTIP can be given orally and reaches the brain in sufficient amounts to block more than 90% of CRF receptors.

But MTIP does not accumulate in other organs, including the liver, in ways that would cause concerns about potential side effects, they add.

Dr George Koob, of the Scripps Research Institute said: "This study shows the activity of a compound that potentially could be used in human subjects.

"It moves the field closer to the day when the dark side of addiction is treated."

The researchers say that, in addition to alcoholism, MTIP might be useful in the treatment of depression or anxiety disorders, in which CRF levels can also be high.

Bob Patton, a health psychologist at the National Addiction Centre, King's College London said: "This study certainly shows promise.

"Alcoholism is a chronic relapsing condition with up to nine out of 10 patients return to drinking after treatment, and any intervention that can reduce this would be welcomed.

"There are many pharmacological and psychological approaches that can help patients remain sober; however none have proved to be definitive.

"The worth of MTIP needs to be explored in a properly conduced clinical trial. If successful, this could be a useful addition to our existing treatment arsenal."

RELATED INTERNET LINKS
Journal of Neuroscience
National Addiction Centre
The BBC is not responsible for the content of external internet sites