SCOTTSDALE, ARIZ. – Memantine, the Alzheimer's drug, could have a new use: alcohol-dependence treatment.
In a small pilot study of 16 people who met Diagnostic and Statistical Manual criteria for alcohol dependence and who were treated with memantine for 8 weeks, drinking behavior declined, Dr. Albert J. Arias said in a poster presentation at the annual meeting of the American Academy of Addiction Psychiatry.
The mean number of drinking days reported by the subjects declined 18% during the 8 weeks of the study, compared with the weeks before treatment. The mean number of heavy drinking days declined 22%, and the mean number of drinks per drinking day declined by two.
Moreover, all except three people had a decrease in the number of drinks per drinking day, all except four people had a decrease in drinking days, and all except five had a decrease in heavy drinking days.
The trial was promising more than it was definitive, since there were no control subjects for comparison. The participants also received seven sessions of counseling and were enrolled because they had a stated desire to reduce their alcohol intake.
The investigators would have liked to have seen a bigger impact, said Dr. Arias, of the Alcohol Research Center at the University of Connecticut, Farmington, in an interview.
“Our impression is that we significantly underdosed,” he said.
The dose used started at 5 mg per day and was titrated up by 5 mg a week to 20 mg a day. All except one of the 16 patients completed the study. That patient complained of fatigue, the most common adverse effect of the medication. A dosage reduction did not alleviate his fatigue.
Still, overall, the drug was well tolerated.
The other patients who initially experienced fatigue reported that their fatigue diminished over time, Dr. Arias said.
Some of the participants reported that the drug seemed to produce a rapid improvement in their cognitive functioning and in their sleep patterns. Dr. Arias said he believes that a dose of 60–80 mg a day might be more effective. That dose has been shown to be tolerable.
At Columbia University, New York, another research group has already begun a trial using a dose of 60 mg a day, he added.
Memantine is an N-methyl-D-aspartate (NMDA) receptor antagonist, and NMDA receptor function has been implicated in alcohol dependence. In human laboratory studies, it has been found to reduce alcohol craving.