Ketamine’s Antidepressant Effect May Depend on Opioid System
Previous studies of ketamine have focused on glutamate, but the new finding showing activation of opioid receptors shows why repeated use of ketamine may produce tolerance and addiction.
The antidepressant effects of ketamine appear to depend on activation of the brain’s opioid receptors, underscoring the drug’s addictive potential, according to a report published this week in AJP in Advance.
When 12 patients with treatment-resistant depression were treated with the opioid antagonist naltrexone before receiving an infusion of ketamine, the antidepressant effects of ketamine were dramatically diminished.
“The implications for future research and clinical use of ketamine are potentially profound,” senior author Alan Schatzberg, M.D., the Kenneth T. Norris, Jr., Professor of Psychiatry and Behavioral Sciences at Stanford University School of Medicine, told Psychiatric News. Schatzberg is a past president of APA. Dr. Schatzberg shares senior authorship of the paper with Carolyn Rodriguez, M.D., Ph.D., assistant professor of psychiatry at Stanford. Lead authors of the study were Nolan R. Williams, M.D., an assistant clinical professor of psychiatry at Stanford, and Boris Heifets, M.D., Ph.D., an assistant clinical professor of anesthesiology at Stanford.
Ketamine, which was approved as an anesthetic in 1970, has been the object of enormous interest in the last several years for its ability to rapidly reduce symptoms of depression and acute suicidality. Hundreds of ketamine infusion centers have sprung up around the country offering off-label treatment for mood disorders.
Author: Mark Moran
Source: Psychiatric News Online