Effects of Carvedilol on Cocaine Use in Humans - 11

The purpose of this study was to determine whether carvedilol, and alpha and beta adrenergic
blocker, would inhibit the priming effect of cocaine in a laboratory model. A total of 12
subjects were enrolled in this double blind, placebo controlled, outpatient study. After an
adaptation session, three experimental sessions were held, 2-9 days apart. On each of 3
experimental sessions, a single oral dose of low (25mg) or high dose of carvedilol (50mg) or
placebo were administered. Two hours following carvedilol or placebo treatment, subjects
received a priming dose of smoked cocaine, 0.4 mg/kg. during the second part of the session,
subjects had the option to earn up to 2 tokens by working on a computer task that could
later be exchanged for money or deliveries of cocaine. We proposed that blockage of
adrenergic receptors by carvedilol would significantly alter the subjective and
physiological effects of cocaine.

Inclusion Criteria:

Male/Female between 20 and 55. History of smoked or intravenous cocaine use on the average
of at least once a week over a 6 month period. current history of good health and normal
EKG. Not pregnant as determined by pregnancy screening nor breast feeding, using
acceptable birth control methods (e.g. birth control pills diaphragm, condoms plus foam)

Exclusion Criteria:

Current problems with major psychiatric illnesses including bipolar disorder,
schizophrenia, or anxiety disorders. History of major medical illnesses including asthma
and chronic obstructive pulmonary disease. Currently on a drug related parole or
probation. Treated for chemical dependency withing the past 6 months.