Ketamine, known for its rapid-acting antidepressant effects, is often coadministered with other psychoactive drugs, including opioids and cannabinoids, in both clinical and recreational settings. We investigated whether ketamine (R-, S-, or racemic R, S-) isoforms alter the subjective effects of morphine or Δ9-tetrahydrocannabinol (THC) and whether the interoceptive effects of ketamine overlap...
Studies in non-human animals suggest that opioid antagonists block the reinforcing effects of cannabinoids. The present studies in humans investigated how naltrexone modulates (1) the subjective and physiological effects of oral THC in comparison to methadone, (2) the reinforcing effects of oral THC, and (3) plasma levels of oral THC. In study 1, marijuana smokers (n=9) received naltrexone (0,...