for people ages 21-40 (full criteria)
healthy people welcome
at San Francisco, California and other locations
study started
estimated completion
Jennifer Mitchell



The purpose of this study is to determine the effects of tolcapone on decision making and alcohol intake using a laboratory bar (on-site alcohol self-administration) in alcohol drinkers.

Official Title

Effects of Tolcapone on Decision Making and Alcohol Intake Using a Laboratory Bar in Moderate to Heavy Social Drinkers


The study is a 7-session, double blind, placebo-controlled crossover study of the effects of tolcapone, the COMT inhibitor, on decision making and alcohol intake using a laboratory bar in moderate to heavy social alcohol drinkers. Subjects will be moderate to heavy social users of alcohol, defined as at least 10 standard drinks per week for women and at least 14 standard drinks per week for men. There will be one screening session followed by six additional visits including 2 laboratory bar sessions. On each study drug administration day, subjects will come in to the clinic for a medication dispensation visit and instructions on when and how to take the study drug for the remainder of the study. Study drug bottles will be equipped with MEMS caps to ensure compliance. After 5 days of drug administration, subjects will return to the clinic for a laboratory bar. This session will consist of administration of a standardized laboratory bar paradigm and a series of computerized and written decision-making tasks. Subjects will then be crossed over and complete the same series of study visits on the alternate study drug.


Alcohol Abuse Impulsive Behavior Alcoholism Alcohol Drinking Ethanol Tolcapone


You can join if…

Open to people ages 21-40

  • Healthy volunteers who are 21-40 years of age
  • If female, 10 or more alcoholic drinks must be consumed weekly.
  • If male, 14 or more alcoholic drinks must be consumed weekly.
  • Meets DSM-V criteria for Alcohol Use Disorder (AUD).
  • If female, must be non-lactating, not pregnant, and using a reliable contraception method (i.e. abstinence, intrauterine device [IUD], hormonal birth control, or barrier method).
  • Ability to read and speak English.
  • High school graduate.
  • Able and willing to provide an informed consent.
  • Able to understand and follow the instructions of the investigator, including the delayed discounting tasks. Residing within 5 miles of the study site.

You CAN'T join if...

  • Positive urine drug screen (except marijuana).
  • Using cocaine, stimulants (other than nicotine and caffeine), amphetamines, hallucinogens, ecstasy, opiates, sedatives, pain pills, sleeping pills. or other psychoactive drugs within 2 weeks of the start of the study (except marijuana).
  • Marijuana use more than 3 times/week.
  • Current enrollment in an alcohol, or other drug treatment program or current legal problems relating to alcohol, or other drug use.
  • Currently trying to quit alcohol use.
  • History of major alcohol related complications within the preceding 2 years (liver failure/cirrhosis, pancreatitis, esophageal varices, etc.).
  • Two SGPT/ALT or SGOT/AST values greater than the upper limit of normal.
  • Unable to pass the Standard Field Sobriety Test in a sober state (BAC = 0.00).
  • BAC level >0.05% at the beginning of screening visit (within margin of error of detection).
  • Regular use of any of the drugs on the tolcapone contraindications list OR within 2 weeks of drug administration.
  • Severe low blood (< 90/50) pressure or uncontrolled high blood pressure (>160/100). Allergy or intolerance to tolcapone.
  • Subject has received an investigational drug within 30 days of the screening visit.
  • Subject is considered unsuitable for the study in the opinion of the investigator or clinician for any other reason (such as an Axis II personality disorder that makes the subject unable to comply with study instructions, per the Clinician's judgement.)


  • University of California, San Francisco
    San Francisco California 94109 United States
  • University of California, Berkeley
    Berkeley California 94704 United States

Lead Scientist

  • Jennifer Mitchell
    I conduct translational neuroscience research that rests at the intersection of psychology, pharmacology, and genetics. My work is focused on understanding the neural mechanisms responsible for decision-making, impulsivity, and other mechanisms in relation to drug and alcohol abuse, and on developing novel treatment strategies for these disorders.


in progress, not accepting new patients
Start Date
Completion Date
University of California, San Francisco
Phase 2
Study Type
Last Updated