LSD Could Offer a Next-Gen Treatment for Anxiety

One person’s acid trip could be another person’s anxiety therapy. That’s the tantalizing upshot from a new study that showed LSD may have the potential to alleviate anxiety. The findings are just the latest in a string of studies that suggest the psychedelic could help treat a range of mental health conditions.

The phase II trial detailed in this study was sponsored by a company called MindMed, which has been developing a proprietary form of LSD code-named MM-120. In the trial, people with generalized anxiety disorder who took LSD experienced a significant reduction in their anxiety symptoms compared to placebo.

The company is already conducting larger phase III trials of MM-120 for both anxiety and depression, with results expected next year.

“This study is a true turning point in the field of psychiatry,” said study author Maurizio Fava, chair of the department of psychiatry at Mass General Brigham and MindMed scientific advisor, in a statement. The team’s findings were published Thursday in the journal JAMA.

Psychedelic medicine

Psychedelics like LSD and psilocybin (the active ingredient in magic mushrooms) have received renewed scientific attention in recent years as potential treatments for mental health conditions. Aside from causing feelings of euphoria and disassociation—qualities that make them popular recreational drugs—there is evidence to suggest psychedelics positively interact with brain receptors and regions of the brain commonly linked to anxiety, depression, and other psychiatric conditions.

There are numerous clinical trials of LSD to treat various conditions underway. But according to the researchers behind this latest study, it may mark a first for the literature because it is a randomized, placebo-controlled trial testing out varying doses of MM120 for generalized anxiety disorder, without any additional therapy or other intervention.

LSD’s anxiety-reducing potential

The trial involved 198 people diagnosed with moderate to severe anxiety. The participants were either given a placebo or one of four doses of LSD. They were closely monitored for 12 hours (the typical half-life of LSD is three to five hours, although it can take a day for the effects to completely wear off). Then the researchers tracked the participants for 12 weeks.

By the fourth week, the participants who took a 100 or 200 milligram dose of LSD reported significantly greater reduction in anxiety symptoms compared to the placebo group. Notably, participants who took a smaller 25 or 50 milligram dose of LSD may also have benefited, but the difference wasn’t statistically significant.

For those who did see significant changes, the improvement was often sustained as well, with nearly half of the 100 or 200 milligram participants considered to be in remission for their anxiety by week 12, compared to only 20% of the controls.

There were a few mild adverse events in line with the known side effects of LSD, with some participants reporting hallucinations or visual distortions, nausea, and headaches. Nearly everyone who took a 100 milligram-or-higher dose experienced visual changes.

The future of LSD as therapy

Phase II trials are primarily designed to affirm the safety of an experimental drug. So these results should not be taken as proof that LSD works as an anxiety drug. But the data are certainly encouraging.

MindMed has launched three phase III trials of MM-120, two of which are for generalized anxiety and, based on the earlier data, participants will be given a 100 milligram dose. These trials, if they’re successful, will provide the evidence needed for the Food and Drug Administration and other regulators to consider LSD as a legitimate treatment for anxiety.

Still, psychedelic medicine remains largely outside the mainstream. In 2019, the FDA approved a derivative of ketamine (Johnson and Johnson’s nasal spray drug Spravato) for treatment-resistant depression. But in 2024, it declined to approve MDMA-assisted therapy for post-traumatic stress disorder, citing a need for additional phase III data from the treatment’s sponsor, Lykos Therapeutics (Lykos is planning to do the work requested). MindMed’s journey toward FDA approval will depend on the strength of their trial findings, but this initial data at least suggests they have a promising road ahead.