Study finds caffeine outperforms LSD microdosing for depression treatment

A decade back, the concept of microdosing captured media attention as a Silicon Valley wellness trend promising mental health benefits without the full psychedelic experience. Practitioners of this approach—typically involving psilocybin or LSD in minimal quantities—sought mood elevation and sharper focus rather than visual hallucinations or perceptual distortions.

Anecdotal accounts portrayed microdosing as a multipurpose remedy, credited with enhancing concentration, boosting libido, and notably, reducing depression symptoms. Skeptics questioned whether such minuscule doses could deliver meaningful effects. A recent investigation by Melbourne-based MindBio Therapeutics now suggests these claimed benefits may be significantly exaggerated, particularly regarding clinical depression treatment.

MindBio's Phase 2B trial enrolled 89 adults to evaluate LSD microdosing for major depressive disorder. Over eight weeks, researchers measured depression using the Montgomery-Åsberg Depression Rating Scale (MADRS), an established clinical assessment tool. The unpublished findings revealed that LSD-treated participants actually performed worse than those receiving a placebo—a caffeine pill.

Participants received LSD doses between 4 and 20 micrograms, well below hallucinogenic thresholds. While these patients reported improved well-being, their MADRS scores declined compared to the placebo group. MindBio CEO Justin Hanka announced the results on LinkedIn, describing it as "the most vigorous placebo controlled trial ever performed in microdosing."

The implication is striking: a standard cup of coffee may offer greater therapeutic benefit for major depressive disorder than a microdose of acid. Hanka acknowledged the implications, stating "It's probably a nail in the coffin of using microdosing to treat clinical depression. It probably improves the way depressed people feel—just not enough to be clinically significant or statistically meaningful."

The placebo effect explanation

These outcomes align with earlier skepticism from researchers who attributed microdosing's perceived benefits to expectation rather than pharmacology. In 2020, Jay A. Olson, then pursuing his PhD at McGill University's Department of Psychiatry in Montreal, conducted a revealing experiment with 33 participants.

Olson's team administered a placebo while telling subjects it contained a psilocybin-like compound, with no mention of a control group. Confederate researchers performed drug effects in an environment designed with psychedelic aesthetics. The resulting paper, "Tripping on Nothing," demonstrated that most participants reported experiencing drug effects despite receiving nothing active.

Now a postdoctoral fellow at the University of Toronto, Olson explained to WIRED: "The main conclusion we had is that the placebo effect can be stronger than expected in psychedelic studies. Placebo effects were stronger than what you would get from microdosing."

Olson emphasized that public understanding of placebo effects remains limited. "The public has a lot of misconceptions about the placebo effect," he noted. "There's this assumption that placebo effects are extremely weak, or that they're not real." In psychedelic research, he suggests, hype surrounding the drugs themselves amplifies expectation effects, allowing participants' minds to generate experiences matching their anticipated outcomes.

Olson's perspective reframes the question: "It can be true at the same time that microdosing can have positive effects on people, and that those effects are perhaps almost entirely placebo."

Trial design and competing interpretations

MindBio's methodology employed a "double-dummy" design, informing participants they might receive LSD, caffeine, or methylphenidate (Ritalin or Concerta). This structure diluted patient expectations, as perceived effects could be attributed to any of the three substances. No participants actually received methylphenidate. All followed the "Fadiman protocol," a standard microdosing schedule involving doses every three days.

Jim Fadiman, the 86-year-old psychedelic researcher whose name the protocol bears, rejected both MindBio's conclusions and experimental design. He argued that the active caffeine placebo itself—not a pure placebo effect—likely accounted for reported benefits. "Double-dummy is a remarkably apt term," Fadiman said sarcastically. "What I know is that if you take enough caffeine, you will not be depressed!"

Fadiman pointed to MindBio's earlier Phase 2A trial, published in Neuropharmacology, which produced markedly different results. That open-label study—where patients knew they were receiving LSD—showed MADRS scores decreased by 59.5 percent, with benefits persisting up to six months and improvements in stress, rumination, anxiety, and quality of life. "Their prior study did wonderfully with LSD," Fadiman said. "I have collected literally hundreds of real world reports over the years that validate those findings."

Hanka defended the Phase 2B methodology, stating: "We are bewildered at the significant difference between the open label Phase 2A trial results and the Phase 2B trial results. But that is the nature of good science—a properly controlled trial will get a proper result. Our Phase 2B trial was of the highest standard, a triple-blind, double-dummy, active placebo controlled trial. I haven't seen another psychedelic trial that has gone to these lengths to control and blind a trial."

The believer's perspective

Some microdosing advocates remain unmoved by the findings. Ayelet Waldman, author of the Mommy-Track Mysteries series and the 2017 memoir A Really Good Day documenting her personal microdosing experiments for mood disorder treatment, expressed indifference to placebo explanations. "In my book I took very seriously the possibility that what I was experiencing was the mother of all placebo effects," Waldman told WIRED. "I wrote about this a number of times in various chapters and decided in the end it didn't matter. What mattered was that I felt better."

If effects prove measurable and reproducible, the distinction between pharmacological action and placebo response may seem academic. Yet the practical question remains: why would someone undertake legal risks associated with Schedule I controlled substances for benefits potentially achievable through conventional means?

Hanka appears ready to move forward. His next venture is "Booze A.I.," a smartphone application employing artificial intelligence to analyze voice biomarkers for blood alcohol concentration estimation. He has distanced himself from microdosing research. "I put millions of dollars into this myself," he said. "Had I known six years ago what I know about psychedelics, I probably wouldn't have ventured into the microdosing field."