U.S. Psychedelic Use and Microdosing in 2025

Key Findings

• Approximately 10 million U.S. adults microdosed psilocybin, MDMA, or LSD in the past year.
• The top five psychedelic substances used by U.S. adults in 2025 were psilocybin, MDMA, Amanita muscaria mushrooms, ketamine, and LSD.
• Psilocybin was the most used psychedelic substance, with approximately 11 million U.S. adults using it in the past year.
• Among U.S. adults who used psilocybin in the past year, 69 percent microdosed at least once during that period. The comparable figures for LSD and MDMA were 65 percent and 59 percent, respectively.
• The aggregated number of days that U.S. adults used psilocybin in the past year exceeded 200 million, and nearly half of these days involved microdosing.

This is the first study from the 2025 RAND Psychedelics Survey, which was fielded in September 2025 to a probability-based, nationally representative sample¹ of 10,122 adults ages 18 years and older living in the United States at that time. This study presents top-line results on the use of 11 psychedelic substances and detailed information about the prevalence and frequency of microdosing (i.e., taking a small fraction of a full dose, often intermittently on a schedule) for psilocybin, LSD, and MDMA. These results should be of interest to those contemplating changes to psychedelics policies, researchers interested in use patterns (especially for microdosing), and others interested in learning more about these substances.

Background

Psychedelic substances²—such as psilocybin mushrooms, MDMA, LSD, and ibogaine—have long been touted as holding promise for treating various mental health conditions. Although medical research into the potential benefits and risks of psychedelic substances has increased, there is still a lot to learn about the use of these substances outside clinical settings. There is some evidence that the use of some of these substances, especially psilocybin mushrooms, is increasing in the United States (Rockhill et al., 2025). Although the supply and possession of many psychedelic substances are federally prohibited in the United States—with some exceptions (see Kilmer et al., 2024)—increasing numbers of U.S. states and localities have changed or are considering changing their policies on some psychedelic substances (Andrews et al., 2025). Additional data on the use of these substances in the United States are needed to inform policy debates.

Dosing practices are an area of particular unknowns with potential health implications. Psychedelic substances are sometimes taken in microdoses. Microdosing is defined as taking a small fraction of a full dose, often on a schedule over multiple days or weeks (Marks et al., 2023). Although there is no official standard for what constitutes a microdose of psilocybin, a commonly used measure is 10 percent or less of the regular dose one would take to feel the full perception-altering effects of the substance (Szigeti et al., 2021). A nationally representative survey fielded in 2023 found that about 47 percent of those who used psilocybin mushrooms in the past year reported microdosing the last time they used the substance (Kilmer et al., 2024).³ Those who microdose report doing so for many reasons, ranging from managing anxiety and depression symptoms to improving mood and creativity (Nutt, 2024; Lea et al., 2020). A few clinical trials have focused on microdosing (Petranker et al., 2024; Murphy, Muthukumaraswamy, and de Wit, 2024; Mueller et al., 2025), and one review of the microdosing literature has called for more research on implications for cardiac fibrosis and valvulopathy (Rouaud, Calder, and Hasler, 2024).

Some other national surveys ask respondents about their use of psychedelic substance, but each has limitations. Additionally, the consumption of psychedelics by U.S. adults is rapidly changing, creating a need for the most-current data as possible. The National Survey on Drug Use and Health (NSDUH), which recently released top-line results for 2024, is the main source of nationally representative data on substance use and includes some questions about recent use of some psychedelics (e.g., past-year use of psilocybin was added in 2024) (Substance Abuse and Mental Health Services Administration, 2025). However, the NSDUH does not cover all substances that are part of current policy discussions—for example, specific questions about the use of ibogaine are not included in NSDUH. Another source, the National Survey Investigating Hallucinogenic Trends (NSIHT), also collects data about past-year use of psychedelics from a nationally representative sample, but neither the NSDUH nor NSIHT asks respondents about whether they microdosed when using these substances (Rocky Mountain Poison and Drug Safety, 2025).

This study contributes to existing nationally representative data sources with population-weighted estimates of past-year use of psychedelics by U.S. adults from data collected in September 2025. We estimate the proportion of adults in the United States who have used in the past year, including psilocybin, MDMA, ketamine, LSD, and Amanita muscaria mushrooms.⁴ Then, we present groundbreaking estimates for how many U.S. adults have microdosed psilocybin, LSD, and MDMA in the past year. We also show a comparison of the number of days that U.S. adults used psilocybin, LSD, and MDMA in the past year and what share of those days involved microdosing.

All estimates in this study are based on self-reported survey data. For simplicity of presentation, we refer to these responses as use in this study, although these responses represent respondents' self-reports rather than confirmed use. Readers should also note that microdosing can be difficult to define and whether individuals microdosed is self-reported in these data.

Psilocybin Was the Most Used Psychedelic Substance in 2025, and Amanita Muscaria Mushrooms Are Also in the Top Five

We asked respondents, “Have you ever used any of these substances in your lifetime? Select yes for any substance you've ever used, even if you only tried it one time or it was many years ago.” The list of substances consisted of alcohol, cannabis, and a variety of psychedelic substances. For respondents who reported that they had used any of these substances, we then followed up with questions about how recently they had last used the substance. Figure 1 shows past-year use rates, and Table 1 shows population estimates for the use of the following psychedelic substances:⁵

• psilocybin mushrooms (also known as magic mushrooms) or synthetic psilocybin—not including Amanita muscaria mushrooms (also known as fly agaric mushrooms)
• MDMA (also known as ecstasy or Molly) or MDA
• Amanita muscaria mushrooms (or fly agaric mushrooms)
• ketamine
• LSD (also known as acid)
• DMT (also includes ayahuasca, huasca, or yagé)
• mescaline (also known as peyote or San Pedro)
• 2C-B or other synthetic phenethylamines
• Salvia divinorum (also known as diviner's sage)
• ibogaine or iboga
• 5-MeO-DMT (also known as 5 or toad).

Substance	Past-year use by adults in the United States
Psilocybin	4.3 percent
MDMA or MDA	1.8 percent
Amanita muscaria	1.3 percent
Ketamine	1.3 percent
LSD	1.1 percent
DMT	0.8 percent
Mescaline	0.5 percent
2C-B	0.5 percent
Salvia divinorum	0.4 percent
Ibogaine or iboga	0.4 percent
5-MeO-DMT	0.3 percent

SOURCE: Features information from the authors’ complete case analysis of respondents (N = 10,122) from RAND Psychedelics Survey data from September 2025 using population weights.

NOTE: Each bar shows the estimated percentage of U.S. adults who used that specific substance in the past year (past-year use prevalence) from national survey data.

Substance	Past-Year Use Population Estimate		95% CI
			Lower	Upper
Psilocybin	11,059,000		9,404,000	12,715,000
MDMA or MDA	4,699,000		3,765,000	5,634,000
Amanita muscaria	3,469,000		2,657,000	4,282,000
Ketamine	3,268,000		2,443,000	4,093,000
LSD	2,982,000		2,196,000	3,768,000
DMT	2,189,000		1,250,000	3,128,000
Mescaline	1,375,000		833,000	1,916,000
2C-B	1,201,000		679,000	1,723,000
Salvia divinorum	1,112,000		616,000	1,608,000
Ibogaine or iboga	941,000		434,000	1,449,000
5-MeO-DMT	769,000		340,000	1,198,000

SOURCE: Features information from authors' complete case analysis of N = 10,122 respondents from RAND Psychedelics Survey data from September 2025 using population weights.

NOTE: Population estimates are weighted to represent approximately 259 million U.S. adults ages 18 years and older. Estimates rounded to the nearest thousand.

Psilocybin stands out with a past-year prevalence rate of 4.3 percent, approximately 11 million U.S. adults.⁶ Other psychedelic substances in the top five for past-year use are MDMA/MDA (1.81 percent—approximately 4.7 million U.S. adults), Amanita muscaria mushrooms (1.34 percent—approximately 3.5 million U.S. adults), ketamine (1.26 percent—approximately 3.3 million U.S. adults), and LSD (1.15 percent—approximately 3 million U.S. adults).

Approximately 10 Million U.S. Adults Microdosed Psilocybin, LSD, or MDMA in the Past Year

We asked respondents who reported using psilocybin,⁷ LSD, or MDMA in the past year how many days in the past year they used each substance and how many of those days they microdosed. We defined microdosing in the survey questions as “taking a small fraction of a regular dose (a subperceptual dose) that is much lower than you would take to ‘trip’ or hallucinate on these substances.” Although our survey only asked questions about microdosing for psilocybin, MDMA, and LSD, there are also reports of other psychedelic substances listed in Figure 1 being microdosed—for example, ketamine and Amanita muscaria (Syed et al., 2024; Leas et al., 2024).

Figure 2 shows weighted estimates of the proportion of U.S. adults who have microdosed each substance at least one day in the past year, according to the 2025 RAND Psychedelics Survey data. Among U.S. adults who reported to have used each substance in the past year, we estimated that 69 percent microdosed psilocybin, 65 percent microdosed MDMA, and 59 percent microdosed LSD at least one day.

Substance	Did not report microdosing	Reported microdosing at least once
Psilocybin	31 percent	69 percent
MDMA	35 percent	65 percent
LSD	41 percent	59 percent

SOURCE: Features information from authors’ complete case analysis of RAND Psychedelics Survey data from September 2025 using population weights.

NOTE: These estimates were based on the following unweighted samples for the number of respondents reporting use of each substance in the past year: psilocybin, n = 372; MDMA, n = 163; LSD, n = 90. These sample sizes reflect the unweighted number of respondents reporting use of each substance in the past year, while percentages reflect survey-weighted estimates to reflect the U.S. adult population who microdosed each substance at least one day in the past year. Note that these are proportions from among the weighted past-year use estimates for the U.S. adult population for each substance, which are 4.3 percent for psilocybin, 1.8 percent for MDMA, and 1.1 percent for LSD.

According to survey responses, we estimated that approximately 9.5 million U.S. adults microdosed one or more of psilocybin, MDMA, or LSD in the past year (about 3.7 percent).⁸ This total reflects an overlap-adjusted estimate of unique individuals who microdosed. Among the 9.5 million adults we estimated to have microdosed psilocybin, MDMA, or LSD, we estimated that 16 percent microdosed more than one of these three substances in the past year.

Figure 3 shows weighted estimates for the share of use days U.S. adults microdosed in the past year by substance for psilocybin, MDMA, and LSD. For psilocybin, we estimated approximately 216 million use days in the past year, of which approximately 102 million involved microdosing (47 percent). For MDMA, we estimated approximately 62.5 million use days in the past year, of which approximately 26.5 million involved microdosing (42 percent). For LSD, we estimated approximately 21 million use days in the past year, of which approximately 8.6 million involved microdosing (41 percent).

Substance	Use days not involving microdosing	Use days involving microdosing
Psilocybin	53 percent	47 percent
MDMA	58 percent	42 percent
LSD	59 percent	41 percent

SOURCE: Features information from authors’ complete case analysis of RAND Psychedelics Survey data from September 2025 using population weights.

NOTE: These estimates were based on the following unweighted samples for the number of respondents reporting use of each substance in the past year: psilocybin, n = 372; MDMA, n = 163; LSD, n = 90. These sample sizes reflect the unweighted number of respondents reporting use for each substance in the past year, and percentages reflect survey-weighted estimates to reflect the share of microdosing days among the U.S. adult population.

Although microdosing accounts for a noteworthy share of reported past-year use days, it accounts for a much smaller share of the total amount consumed of the substance in the past year. For example, if a typical microdose of psilocybin is 10 percent the size of a regular dose, and one assumes that very few people take a regular dose and a microdose on the same day, then less than 10 percent of the psilocybin consumed in the past year was in the form of microdosing:

$\frac{102M\times 10\%}{\left(114M\times 100\%\right)+\left(102M\times 10\%\right)}\approx 8.2\%.$

Further research into amounts consumed in full doses and microdoses of these substances can aid in generating estimates for the total amount of these substances that are consumed nationwide. Future research could extend such calculations to include the total amount of spending on psychedelic substances attributable to microdoses.

About the RAND Psychedelics Survey

The RAND Psychedelics Survey is a probability-based and nationally representative survey fielded to AmeriSpeak panelists. Funded and operated by NORC at the University of Chicago, AmeriSpeak is a probability-based panel designed to be representative of the U.S. household population. Randomly selected U.S. households are sampled using area probability and address-based sampling, with a known, non-zero probability of selection from the NORC National Sample Frame. The panel provides sample coverage of approximately 97 percent of the U.S. household population. The AmeriSpeak sample has been used in other studies to generate nationally representative estimates in health research (e.g., Kennedy-Hendricks et al., 2024).

Panelists ages 18 and older were asked to complete a survey online or be interviewed over the phone from September 9, 2025, through October 1, 2025, with 10,122 panelists completing the survey with validated responses. The sample includes an oversample of veterans, which was collected for further analyses of veteran-specific topics in a separate report. Population weights, as described below, are designed to account for the oversampling of veterans.

The weighted AAPOR RR3 at the household level for AmeriSpeak panel recruitment is 26.3 percent. A recruited household is a household in which at least one adult successfully completed the recruitment survey and joined the panel.

Survey data were collected by NORC and then provided to RAND researchers for analysis. Weights are created to adjust for nonresponse to benchmarks of household dwelling adults ages 18 years and older in the United States with benchmarks from the March 2024 Current Population Survey (U.S. Census Bureau, 2025).

The margin of error is ±1.33 percentage points and accounts for design effects, including the variation of the final survey weights. Additional information about the data collection methods, including the design of the survey weights, is available at https://www.rand.org/health/centers/dprc/psychedelics.html.