The review was published in the journal Lancet Psychiatry.
In looking back at 83 past studies, only a few showed that marijuana lessened anxiety.
And it came mostly by relieving other symptoms, like pain.
The studies did show twice as many bad reactions among users, compared to a dummy compound.
"There is scarce evidence to suggest that cannabinoids improve depressive disorders and symptoms, anxiety disorders, attention-deficit hyperactivity disorder, Tourette syndrome, post-traumatic stress disorder, or psychosis. There is very low quality evidence that pharmaceutical THC (with or without CBD) leads to a small improvement in symptoms of anxiety among individuals with other medical conditions. There remains insufficient evidence to provide guidance on the use of cannabinoids for treating mental disorders within a regulatory framework. Further high-quality studies directly examining the effect of cannabinoids on treating mental disorders are needed," the review states in its interpretation.
To read the research review, click here.