Microdosing LSD is not an effective ADHD treatment

Taking small, repeated doses of the psychedelic drug LSD doesn’t alleviate ADHD symptoms any more than a placebo.

Microdosing psychedelic drugs involves taking them a few times a week in small enough doses to not experience hallucinations. Although there is little evidence backing it up, there is a pervasive idea that this can boost well-being, creativity and focus. And some studies have shown that people who microdose as a way of treating ADHD do report symptoms improving, but these studies were observational and relied on self-reported data.

To test the drugs’ effects on ADHD more rigorously, Matthias Liechti at the University of Basel in Switzerland and his colleagues conducted the first ever randomised controlled trial of LSD microdosing for ADHD. They recruited 53 adults living in the Netherlands or Switzerland who were diagnosed with ADHD and experienced moderate to severe symptoms. Twenty-seven of the participants took a 20-microgram dose of LSD twice a week – on the higher end of microdoses, but still only about a fifth of a standard dose – while the rest were given a placebo.

ADHD symptoms were assessed at the start of the study and six weeks later using a 54-point scale, where higher scores indicated more severe symptoms. On average, scores decreased by about 7 points in participants taking LSD and nearly 9 points in those given a placebo. This isn’t a significant difference, suggesting that LSD is no better than a placebo at improving ADHD symptoms, says Liechti.

However, it could be that the dosage wasn’t right for treating ADHD, he says. LSD may also need to be taken daily to experience a decrease in symptoms, similar to how current ADHD medications works, says Conor Murray at the University of California, Los Angeles.

“We still need to see whether an acute dose – meaning while the drug is in your body – does that have any reduction in symptoms?” says Murray. “That is kind of the first step. And if it doesn’t, then you almost don’t even have to ask whether there is any enduring change.”