Tripping or microdosing, mushrooms use is on the rise in U.S.

Psilocybin mushroom grown in Littleton, Colo. Use of the psychoactive drug is growing in popularity in the U.S. Hyoung Chang/Denver Post/Getty Images hide caption

toggle caption Hyoung Chang/Denver Post/Getty Images

Psychedelics have entered the mainstream in a big way: Investors have staked billions on potential medical treatments, scientific research has skyrocketed and public sentiment signals growing acceptance.

And yet the major sources of data on drug use have big gaps when it comes to psychedelics, making it hard to gauge exactly how consumption is changing and in what ways.

Two reports out this week offer some much-needed data points on the public’s psychoactive preferences. Together, they suggest that magic mushrooms containing the compound psilocybin are now the most popular choice. And many people are opting to microdose, consuming a fraction of the usual dose, rather than taking a full trip.

“We've known that microdosing has become a cultural phenomenon, but all the surveys on drug use don’t ask about dosing,” says Eric Leas, an epidemiologist at the University of California, San Diego, whose research was published on Friday in JAMA Health Forum.

That study tracked internet search history on microdosing -- a proxy for public interest -- finding a more than 1,250% increase since 2015. And searches for psilocybin started to outpace LSD in 2019.

Meanwhile, a separate report from the non-partisan RAND Corporation estimates that about 3% of the American public -- approximately 8 million adults -- have used psilocybin in the past year, making it the most popular hallucinogen in 2023.

The fact that psilocybin use eclipsed other popular psychedelics came as a “surprise” to Beau Kilmer, who co-directs the RAND Drug Policy Research Center and was the lead author of the study, which was published this week.

The runner-up was MDMA, or ecstasy, at just over 1%, followed closely by LSD. The report was based on a nationally representative survey of about 4,000 people and explores the policy implications of changing attitudes around psychedelics.

The impact of decriminalization on microdosing

Nearly half of those who tried psilocybin in the past year said they had elected to microdose, a trend that has caught on in many circles, including tech workers and suburban moms.

While there’s no universal definition of microdosing, Kilmer says it’s often considered to be in the range of 1/10 to 1/20th of a full dose.

Some users dabble in mushrooms. The majority of psilocybin microdosers in the past year said they had taken the drug on just one or two occasions, while only about 11% said they had taken the substance more than six days.

More than half said they consumed “whole, fresh, or dried mushrooms,” close to a quarter took it in a “processed form” like a chocolate bar, and about 14% imbibed a tea or drink.

The uptick in online curiosity around microdosing correlates with changes in the law or policy related to both cannabis and psychedelics.

“There was a stepwise increase to where the more and more liberal the state got to substance use, the more microdosing interest you saw within the state,” says UCSD’s Leas.

For example, the top states were Oregon and Colorado, both states decriminalized plant-derived psychedelics, although Oregon has recently reigned in some of its legal reforms around drug use.

This type of data analysis has proven to be a reliable indicator for other drugs their lab has studied -- including with novel cannabis products like Delta 8 -- and, Leas says,is “usually really strongly correlated with sales of products.”

Are shrooms the new party drug?

Research suggests that availability of psilocybin has risen in recent years, says Joseph Palamar, an epidemiologist at NYU Langone Health who has found that drug busts for mushrooms have increasedin recent years.

Palamar cautions about drawing too many conclusions from internet search history about whether people are actually using the drugs, but he says the study is a much-needed effort at filling in the blindspots in the epidemiology around psychedelic use.

“We're trying to piece little bits of information together to figure out what is really going on. Ultimately, it would be great if we could harmonize these data somehow, but it’s very difficult,” he says.

Palamar researches trends in drug use in the New York City nightlife scene -- a population that he considers a bellwether for changes in the general population.

“We’ve found that psilocybin use has increased a lot, more than most other drugs,” he says, “I think that's interesting because I usually think of ecstasy and ketamine, I never thought of shrooms as being a big party drug.”

A study published several years ago estimated that about 5.5 million adults had used hallucinogens in 2019 and that LSD use in all age groups had risen from about 1% to 4% since 2002. However, overall research has not caught up with the blossoming of public enthusiasm and media coverage, says Dr. Deborah Hasin, who led that study and is an epidemiologist at Columbia University.

“We need better epidemiology,” she says, “So that we really do know the extent of people’s use, under what circumstances they’re using, how they got the drug and what they even know about what they are taking.”

Not only does the national data collected by the federal government not contain granular information of psychedelics, but for whatever reason it doesn’t explicitly ask whether people have used psilocybin recently, says Kilmer. “Those are really important pieces of information to have in terms of assessing the size of the market and beginning to think about some of the health consequences, whether it be the benefits or the risks.”

A booming and understudied market

When asked why they used the psilocybin, the top three reasons given by respondents to the RAND survey were: fun and social enjoyment, followed by mental health, and personal development and existential exploration.

Dr. Joshua Wooley, director of the Translational Psychedelic Research program at UCSF, says microdosing is a much different model than what’s being rigorously studied in psychedelic clinical trials to treat various mental health conditions.

Those tend to be highly structured around some form of psychotherapy and involve giving the person a very high dose.

“We don't actually know that much about microdosing,” says Wooley.

A recent review of the evidence suggests the practice may improve mood and cognition and that the drug is safe in this context; however, others who’ve analyzed the data say it’s premature to “draw any conclusions” about the efficacy or safety of microdosing.

Kilmer believes the U.S. has reached an inflection point on psychedelics as some states and localities take various approaches to loosen laws and policies on the substances, which remain illegal under federal law.

The market for psychedelics is quite different from cannabis -- it’s much smaller and primarily driven by infrequent users -- but Kilmer does see clear parallels in how the situation is starting to play out.

“This reminds me a lot of where we were in 2012 [with cannabis],” says Kilmer, ““Now is the time for the federal government to decide: Do they want to get involved and shape what these state markets look like? Or do they want to stand on the sidelines and just watch it?”