Horse tranquiliser ketamine could help alcoholics say no to drinking

Source: https://www.telegraph.co.uk/

Sarah Knapton, science editor

26 NOVEMBER 2019

A one-off infusion of the horse tranquiliser ketamine could help heavy drinkers reduce their alcohol intake, by switching off the feeling of reward, scientists have shown.

In an experiment involving 90 people who regularly consumed 30 pints of beer a week, scientists were able to retrain the brains of participants using the drug.

Participants on ketamine were told they were to receive a pint of beer, but scientists at University College London (UCL) then refused to hand over the alcohol.

Although that would have normally triggered a mental response of disappointment and loss, the drug prevented those memories from occurring, resetting their reward centres.

In the following 10 days, trial participants reported less urge to drink beer and in the following nine months their alcohol intake decreased considerably.

“We found that heavy drinkers experienced a long-term improvement after a very quick and simple experimental treatment,” said the study’s lead author, Dr Ravi Das of UCL Clinical Psychopharmacology Unit.

“Learning is at the heart of why people become addicted to drugs or alcohol. Essentially, the drug hijacks the brain’s in-built reward-learning system, so that you end up associating environmental ‘triggers’ with the drug. These produce an exaggerated desire to take the drug.

“Unfortunately, once these reward memories are established, it’s very difficult to re-learn more healthy associations, but it’s vital in order to prevent relapse.”

Ketamine, is already used clinically as a sedative or pain reliever in the NHS, but researchers said more trials would be needed before it could be used to help treat alcoholism.

The drug could also soon be used to treat depression after recent trials showed it is up to 10 times more effective than current drugs in people suffering from treatment-resistant depression. There have been no new drugs for depression in the last 35 years.

Commenting on the findings, Prof Celia Morgan, Professor of Psychopharmacology at the University of Exeter, said: “The idea is really intriguing and follows up other work blocking drug use behaviours by using similar drugs to interfere with reconsolidation in animals.

“Ketamine is an addictive substance and associated with harms to bladder and a risk of accidents, so we have to be cautious when using it in groups who are prone to addictive behaviours.

“But this is important work trying to drive the science of ketamine and memory forwards.”

The research was published in the journal Nature Communications.