This study was the first clinical trial of naltrexone for disordered gamblers. Naltrexone is a drug typically used to dull cravings for alcohol, but Dr. Suck Won Kim and his research team at the University of Minnesota examined the efficacy and safety of naltrexone in the treatment of pathological gambling disorders and hypothesized that its use would reduce uncontrollable urges to gamble and gambling behavior. Kim’s hypothesis was based on clinical and preclinical findings during the period leading up to the study that suggested that opioids could reduce human urges and modulate motivation in animals. Thirty subjects who met criteria for pathological gambling were enrolled in a one-week single-blind placebo lead-in treatment period followed by a twelve-week double-blind naltrexone or placebo treatment. The study’s results showed the naltrexone was effective in stopping cravings and, therefore, stopping the gambling urges. The success of the study led to a grant of $464,463 from the National Institute on Drug Abuse to expand the pilot.
The findings of the pilot study were published in Biological Psychiatry and International Clinical Psychopharmacology in 2001.