The research team recruited 90 people who drank much more than average — an average of about four to five pints of beer a day, or about five times the U.K.’s recommended maximum — but had not previously been diagnosed with alcoholism and were not receiving treatment.
On the first day of the experiment, participants were shown pictures of alcoholic drinks and were asked to rate how strong their urge to drink was. All of them were then allowed to drink a beer.
The next day, they were divided into three groups, and none of them received beer. One group did the exercise in which they saw pictures of drinks — to stimulate their memories — and then received a dose of ketamine. The second group saw the drinks and then got a placebo drug. The final group was shown no pictures and received ketamine.
The results were dramatic. Ten days later, those people who did the memory exercise and got ketamine reported a significant drop in their alcohol intake. A follow-up nine months into the experiment showed that their alcohol consumption was half of what it had been.