Findings lay groundwork for rigorous, clinic-controlled psilocybin safety trials

—Using magic mushrooms and other hallucinogens may lighten the depressive side of bipolar disorder without sending patients into dangerous manic swings, according to a new study in the Journal of Affective Disorders.

Researchers at the University of Texas Health Science Center at Houston tracked people diagnosed with bipolar disorder who had recently taken a psychedelic such as psilocybin. 

They collected day-by-day reports on mood, substance use and other symptoms for the month before and the three months after each participant’s most recent use.

Depressive symptoms fell significantly in the three months after the psychedelic experience, and participants reported more “clean” days free of any mental-health complaints. Cannabis use also dropped. 

Problems that have kept people with bipolar disorder out of most psychedelic trials—mania, psychosis and high anxiety—did not increase.

Lead author Dr. Thomas Meyer, a psychiatry professor, said the pattern raises hope that psychedelics could become a safe option for hard-to-treat bipolar depression if studied in controlled settings.

Roughly 4% of adults live with bipolar disorder. For many, depressive phases last far longer than bursts of mania and resist standard medications. 

Early research suggests psychedelics can rapidly lift depression in other illnesses, but clinicians have worried the drugs might trigger mania in bipolar patients. The new findings challenge that assumption and open the door to rigorous clinical trials.

How the study worked

• Design: Observational survey using a well-validated calendar technique that helps people recall daily experiences.
• Time frame: One month before and 90 days after the psychedelic event.
• Measures: Self-rated mood scales, substance-use tallies and symptom check-lists for mania, psychosis and anxiety.

Because the study relied on participants’ memories and had no placebo group, it cannot prove cause and effect, the authors cautioned. Still, the consistent drop in depression with no sign of mania provides “reassuring preliminary safety data,” they wrote.

Limitations

The sample was small and self-selected, meaning volunteers may differ from the broader bipolar population. All psychedelic use was recreational, so doses, environments and companion support varied widely. The researchers also noted that hallucinogen use itself increased after the initial use, underscoring the need for medical supervision.

What’s next

The Houston team is planning randomized, placebo-controlled trials that would administer standardized doses of psilocybin in a clinic while monitoring participants for weeks. If future studies confirm the drug’s safety and benefit, psychedelics could add a rapid-acting tool to the bipolar-depression toolbox, alongside mood stabilizers and therapy.

The study appeared in the March 15, 2025, edition of the Journal of Affective Disorders (Vol. 373, pp. 505-511).

Note from a person with bipolar I disorder: In my experience, I would not recommend any mind altering substances during a manic episode or between them. There might be an exception for a professional psychiatrist recommending and overseeing the administration of a hallucinogen.