Drugs like nalmefene interfere with opioid receptors. This might reduce drinking. The gene
OPRM1 determines opioid receptor functions. Researchers want to see if nalmefene affects
people s responses to alcohol cues. They also want to compare how nalmefene affects people
with different forms of OPRM1.
To test nalmefene s effects on alcohol self-infusion and responses to alcohol cues. To test
the role of different forms of OPRM1 on these effects.
Healthy heavy drinkers ages 21 60:
Women: over 15 drinks weekly
Men: over 20 drinks weekly
Participants will be screened with:
Heart, blood, and urine tests
Participants will have three 10-hour visits and one 2-hour follow-up visit. They will take a
taxi. Visits are about 1 week apart.
Before visits, participants cannot drink alcohol for 1 day or take medicine for 3 days.
All study visits:
Two-hour alcohol session: A needle guides a thin plastic tube into a vein in each arm. One
tube receives alcohol. The other draws blood. Participants give themselves alcohol by
pressing a button on a computer.
Relaxing at the center until breath alcohol falls below 0.02 percent, or for 3 hours.
Visits 2 and 3:
Swallowing nalmefene or placebo.
One-hour brain MRI: Participants lie on a table with a coil on their head. They press buttons
in response to computer cues.
Follow-up visit: participants will discuss their drinking habits.