Another trial finds no evidence LSD microdosing does anything
Just weeks after a double-blind, placebo-controlled trial found psilocybin microdosing to be no different to placebo, another study has been published that found LSD microdoses have no effect on mood or cognition. The new research builds on a small but growing body of clinical data struggling to find evidence the popular practice of microdosing does anything compared to placebo.
The idea of psychedelic microdosing has exploded in popularity over the past few years. Advocates of the practice claim tiny sub-perceptual doses of psychedelic drugs taken every few days can lead to enhancements in productivity, creativity, mental well-being and energy.
Harriet De Wit, lead author on the new study from the University of Chicago, says that despite the increasing popularity of the practice there is very little controlled clinical research validating the effects of microdosing.
“There are a lot of companies getting into the drug business, either with psychedelic drugs, or drugs like cannabidiol,” said De Wit. “And really there’s not very much empirical support to back up their claims. So, I think we have a responsibility to investigate and validate the claims.”
The new study recruited 56 healthy young adults who were randomly split into three groups – receiving either placebo, 13 micrograms of LSD, or 26 micrograms of LSD. A general “psychedelic” dose of LSD is considered to be anywhere from 100 to 200 micrograms.
Each subject participated in four drug dosing sessions separated by three or four days, designed to simulate the microdosing regime most often anecdotally recommended. During each dosing session the subjects completed a number of cognitive and emotional tasks. A fifth drug-free session was conducted a few days after the fourth session to evaluate any persistent or lingering effects from the microdosing protocol.
Based on anecdotal reporting the researchers expected the microdosing protocol to generate some kind of effect on mood or cognition but to their surprise they could not detect any measurable changes between the three treatment groups on most of the tests conducted. This includes the drug-free follow-up session conducted several days after the microdosing.
Interestingly, the researchers noted most participants reported feeling mild “drug-like” subjective effects after the first 26 microgram dose. Subsequent 26-microgram doses led to diminished subjective sensations, suggesting some tolerance builds to the acute felt effects of LSD. The study also noted small effects were detected on two particular measures of emotional response in the 26-microgram group, “a small decrease in false alarm rates in recognizing fearful emotions and a decrease in feelings of rejection on the social rejection task.”
Importantly, these effects were only detected when subjects were under the acute influence of LSD. All measures had returned to baseline when participants were tested in the drug-free follow-up session, indicating there may be no enduring effects to LSD microdosing.
This is both good news and bad news. Good news for those concerned a few doses of LSD could cause lingering damage but bad news for those looking for any cumulative benefits from microdosing for a couple of weeks.
The researchers do recognize in the study there could still be possible benefits from long-term microdosing that appear when the practice is maintained for more extensive periods of time. Michiel van Elk, lead researcher on a recent psilocybin microdosing trial, addressed this question saying if there were long-term benefits to the practice, sufficiently sensitive tests should detect some kind of effect after two or three weeks.
De Wit is reticent to suggest these findings mean microdosing doesn’t work. Instead, she points out all this study can conclude is that with “this kind of participant, these doses, and these intervals, we didn’t see a robust effect.”
Despite the null effects reported here the study does offer clear evidence these kinds of studies exploring psychedelic microdosing are safe and feasible. It is still early days for clinical research on psychedelic microdosing, and although preliminary studies over the past few years haven't found any evidence the practice actually works, De Wit and her team say the anecdotal evidence is strong enough for researchers to continue investigating.
“Despite our current findings, the anecdotal reports of beneficial effects of the drug remain compelling, suggesting that future studies may detect improvements in mood or performance under other conditions (i.e. greater number of repeated doses or when examined in clinically depressed populations),” the researchers concluded in the new study.
The new study was published in the journal Addiction Biology.