Cannabis Shows Little Benefit for Most Mental Disorders, Review Finds

Cannabis shows little benefit for most mental disorders, review finds, despite growing public faith in medical marijuana.
Many patients use cannabis products for anxiety, trauma, and sleep trouble.
Some also turn to them for substance-use problems.
However, a major new review found weak support for most of those uses.
That finding may surprise many people.
After all, medical cannabis has expanded fast in recent years.
Still, the evidence does not match the hype.

What the Review Looked At

Researchers reviewed 54 clinical trials for the report.
Those studies ran from 1980 through May 2025.
Together, they included 2,477 participants.
The team focused on cannabis-based medicines for mental and substance-use disorders.
Then, they compared the overall results across those studies.
The review appeared in The Lancet, a major medical journal.
So, the findings carry serious weight.

Where Cannabis Fell Short

The review found no strong benefit for several major conditions.
These included anxiety disorders, psychotic disorders, PTSD, and opioid-use disorder.
That matters because many people use cannabis for those exact problems.
Yet the data did not show clear help for routine treatment.
Lead author Jack Wilson said some people may still benefit.
Even so, he said the overall evidence remains weak.
So, doctors and patients should be careful with broad claims.

A Few Areas Showed Promise

The review did find some limited signs of benefit.
A mix of CBD and THC helped some people with cannabis-use disorder.
It reduced withdrawal symptoms and lowered cannabis use.
Researchers also found fewer tics in people with Tourette’s syndrome.
In addition, some patients with insomnia slept longer.
Some people with autism also showed reduced traits.
However, researchers rated the evidence for autism and insomnia as low.

Big Gaps Still Remain

The review found no randomized trials for cannabis as a depression treatment.
That gap stands out because depression affects so many people.
It also shows how thin the research still looks.
Wilson said the field needs better studies with larger groups.
He also said some conditions still need new treatment options.
So, more research matters now more than ever.
Cannabis shows little benefit for most mental disorders, review finds, and that message should shape future debate and medical use.