Influence of cannabidiol on delta-9-tetrahydrocannabinol effects

Clin Pharmacol Ther. 1976 Mar;19(3):300-9. doi: 10.1002/cpt1976193300.


Experiments investigating the possible interaction of tetrahydrocannabinol (THC) and cannabidiol (CBD), two major components of marihuana, were conducted under controlled laboratory conditions in a double-blind manner. In one study, 15 male volunteers were given placebo or 25 mug/kg of THC together with either placebo or 150 mug/kg of CBD by inhalation of the smoke of a single cigarette. All four treatments were assigned to each subject according to a series of Latin-square designs. CBD significantly attenuated the subjective euphoria of THC. Psychomotor impairment due to THC was not significantly altered by the simultaneous administration of CBD, but a trend indicating a decrease in THC-like effects was observed after the combination. When administered alone CBD was inactive for all the parameters measured. In a second study, 8 male subjects were given CBD (0 or 150 mug/kg) by smoke inhalation 30 min before THC (0 or 25 mug/kg) in a second cigarette. In contrast to the simultaneous administration of both drugs, CBD pretreatment did not alter the effects of THC on the parameters observed.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Cannabidiol / pharmacology*
  • Cannabis / pharmacology*
  • Clinical Trials as Topic
  • Dronabinol / pharmacology*
  • Drug Interactions
  • Euphoria
  • Heart Rate / drug effects
  • Humans
  • Male
  • Motor Skills / drug effects
  • Placebos
  • Postural Balance / drug effects
  • Psychological Tests
  • Time Factors


  • Placebos
  • Cannabidiol
  • Dronabinol