ABSTRACT
Introduction
This paper aimed to determine the prevalence, demographic correlates and co‐occurring substance use patterns of hallucinogen microdosing among young adults in the United States.
Methods
Design: Cross‐sectional analysis of data from a nationally‐representative cohort study collected in 2022–2023. Setting: United States. Participants: Sample of 3094 young adults aged 19–30 years in the Monitoring the Future panel study. Measurements: Self‐reported past‐year hallucinogen use and at least one past‐year incident of microdosing, demographic characteristics (age, sex, race/ethnicity, college attendance, parental education) and other substance use (alcohol, cannabis, nicotine, other drugs).
Results
Past‐year hallucinogen use was reported by 9.5% (SE = 0.68) of young adults, with microdosing reported by 6.8% (SE = 0.61). Among those who used hallucinogens, 73.1% (SE = 3.6) engaged in microdosing. Individuals who reported microdosing demonstrated substantially higher rates of other substance use, with odds ratios ranging from 2.53 (95% CI 1.43–4.47) for past‐month cigarette use to 37.73 (95% CI 19.72–72.21) for 3+ occasions of past‐year cannabis use. Among those who microdosed, 72.4% reported 10+ occasions of past‐year alcohol use and 85.8% reported 3+ occasions of past‐year cannabis use. There were few significant demographic differences in microdosing, though Black respondents were less likely (OR = 0.43, 95% CI 0.21–0.90) to microdose compared with White respondents.
Discussion and Conclusions
Approximately 1 in 15 US young adults reported microdosing hallucinogens, with strong associations between microdosing and other substance use. Despite growing interest in potential therapeutic applications of microdosing, the context in which microdosing typically occurs, including patterns of other drug and alcohol use, raises concerns and warrants focused prevention efforts.
Keywords: epidemiology, hallucinogens, microdosing, United States
1. Introduction
Hallucinogenic drugs have psychoactive effects that often include profound alterations in perception, cognition and consciousness. While a number of drug classes produce hallucinogenic effects, psychedelics are among the most commonly used hallucinogens, including lysergic acid diethylamide (LSD, commonly known as ‘acid’) and psilocybin (commonly found in ‘magic mushrooms’ or ‘shrooms’). In recent years, the practice of ‘microdosing’ has gained attention [1, 2, 3], in which small doses of psychedelics are consumed regularly over the course of several weeks to longer [2], often to prompt more subtle changes in mood and behaviour than are experienced with a typical full dose, or to self‐manage depressive, anxiety or substance use disorder symptoms [4, 5, 6]. Data from the 2023 Global Psychedelics Survey indicated that approximately three‐quarters of individuals who ever used psychedelics reported at least one instance of microdosing, and that microdosing was more common in the United States and Canada than in other areas, suggesting an increasingly widespread practice [7].
Yet prevalence and profiles of microdosing in the United States general population remain understudied. Data from a 2022 national survey indicates that overall lifetime hallucinogen use is reported by approximately 6.1% of US adolescents and adults, and past‐year use by approximately 2.2% [8], yet the extent to which these figures represent microdosing remains unknown. Use of hallucinogens is most concentrated among young adults aged 19–30 [8]. In the Monitoring the Future (MTF) panel study, which includes longitudinal assessments of young adults who were sampled nationally in high school, we found that prevalence of non‐LSD hallucinogen use (primarily psilocybin, the most common substance used in microdosing) increased approximately 2‐fold among young adults aged 19–30 in the United States from 2018 to 2021, with past 12‐month use of 6.6% in 2021 [9, 10]. However, data collected specifically on self‐reported microdosing were not yet available at that time.
While individuals report short‐term benefits from microdosing, clinical research is limited [11], and potential health harms associated with microdosing use need further investigation. In particular, patterns of co‐use with other substances are critical to document, given that any potential benefit of microdosing is potentially outweighed in the context of other substance use with known health risks. Previous studies indicate that individuals who use hallucinogens frequently use other substances as well [3, 12], including alcohol, cannabis and other drugs, yet the co‐occurrence of microdosing with other substance use is not well documented.
The present study represents one of the first reports of the national prevalence, correlates and co‐occurring substance use patterns of hallucinogen microdosing in the United States. We focus on young adults aged 19–30 in 2022–2023 given the previous literature highlighting young adulthood as a developmental period in which hallucinogen use is more prevalent than other ages.
2. Methods
2.1. Survey Design
MTF sampled participants in the United States annually and assessed adolescent and adult substance use and other health behaviours [10]. Initially, surveys were completed among students in the 12th grade by nationally‐representative samples in school; a subset of respondents were then selected for longitudinal biennial follow‐up in the MTF panel [10]. Participants were probabilistically selected for longitudinal follow‐up proportional to 12th grade sampling probabilities and enriched for 12th grade substance use. MTF panel participants who were selected for the longitudinal study were randomly assigned to begin follow‐up at either age 19 or age 20; they were interviewed biennially thereafter (i.e., follow‐ups are at modal ages 19/20, 21/22, 23/24, 25/26, 27/28, 29/30). Response rates beginning in the longitudinal follow‐up at 19/20 were mean 61.5% (range 57.7% at age 27 to 76.8% at age 21). Additional information on the MTF panel design can be found elsewhere [10, 13].
The present study was based on respondents who participated in 12th grade from 2010 to 2022, were selected for the MTF panel, and responded to survey versions that included relevant variables when surveyed between ages 19 and 30 in 2022 or 2023 (N = 3177). Among those who were followed‐up, item missing data was minimal; for example, 83 respondents were missing data on hallucinogen use (maximum analytic sample size of 3094) and of those, 234 were missing on microdosing (maximum analytic sample size of 2860). Demographic distributions and other item‐level missingness are described in Table S1. Those with item‐level missing data were removed from analysis pertaining to those items. Analyses were not pre‐registered and thus should be considered exploratory.
2.2. Measures
2.2.1. Hallucinogen Use and Microdosing
Respondents were queried regarding the frequency of hallucinogen use in the past 12 months, including LSD; hallucinogen or psychedelic drugs (‘like PCP, mescaline, peyote, “shrooms” or psilocybin’); and were asked if they ‘micro‐dosed (took a very small amount of) a hallucinogen (like LSD, psilocybin mushrooms, “shrooms”, peyote, etc.)’. Responses were dichotomised into any occasions in the past 12 months versus none.
2.2.2. Other Substance Use
Other substances were queried in various time frames. The number of occasions of past 12‐month use was reported for alcohol use, cannabis smoking, cannabis vaping and other cannabis use (eating in food, drink in a beverage, use a concentrate [such as ‘wax’, ‘budder’ or ‘shatter’] and other methods), and nicotine vaping. The number of days of past 30‐day cigarette use was queried (dichotomized as any days versus no days). Past two‐week binge drinking (5+ drinks in a row) was dichotomised as any occasions versus none. A combined category of other drug use included any past‐12‐month amphetamine, cocaine or tranquilliser use.
2.2.3. Demographics
Data on sex, race and ethnicity and parental education were provided at 12th grade. Sex was asked as, ‘What is your sex?’ (male, female or [starting in 2021] other or prefer not to answer). Due to the small number of respondents who selected other or prefer not to answer, sex analyses included only those selecting male or female. Respondents were allowed to check multiple options for race and ethnicity, and we recoded into mutually exclusive groups based on available sample size: Hispanic, non‐Hispanic White, non‐Hispanic Black and multi‐race/other race. Respondents were asked about each parent's highest level of education; responses were combined based on whether at least one parent had a college degree or higher versus not. At ages 19–30, respondents were queried about whether they attend or attended a 4‐year college. Age was coded based on the modal age at time of survey (19–30).
2.3. Statistical Analysis
Demographic distributions among those who reported past‐year microdosing versus not were estimated, and logistic regressions were estimated generating odds ratios and 95% confidence intervals. Similar models were estimated for any past‐year hallucinogen use. The prevalence of other substance use was estimated among those who reported past‐year microdosing versus not, and among those who reported any past‐year hallucinogen use versus not, and multinomial logistic regressions were estimated generating odds ratios and 95% confidence intervals. Analysis weights [13] accounting for selection probabilities, complex survey design and a wide range of individual characteristics associated with the probability of participation at each modal age (e.g., 12th grade demographics, substance use, grades, truancy; [13]) were incorporated into all analyses using SAS survey procedures.
3. Results
Past‐year hallucinogen use was reported by 9.5% (SE = 0.68) of the analytic sample age 19–30, and past‐year microdosing was reported by 6.8% (SE = 0.61). Of those who reported past‐year hallucinogen use, the majority, 73.1% (SE = 3.6), reported microdosing.
Table 1 shows the demographic correlates of past‐year microdosing and any hallucinogen use. Correlates were largely similar in direction and magnitude between microdosing and any hallucinogen use. For microdosing, no significant differences in microdosing emerged by sex, age, college status or parental education. Black respondents were significantly less likely (odds ratio [OR] 0.43, 95% confidence interval [CI] 0.21–0.90) to microdose compared with White respondents. For any hallucinogen use, females (OR 0.62, 95% CI 0.46–0.85) and Black respondents (OR 0.35, 95% CI 0.19–0.66) were significantly less likely to use than males and White respondents, respectively. Prevalence of use did not significantly differ between 2022 and 2023 for microdosing or any hallucinogen use.
TABLE 1.
Association between sample demographics and past‐year microdosing and any past‐year hallucinogen use among young adults aged 19–30 in the United States from 2022 to 2023.
| Past‐year microdosing | Bivariate logistic regression models | Past‐year any hallucinogen use | Bivariate logistic regression models | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n (yes) | % (yes) | SE | p * | OR | 95% CI | p ** | n (yes) | % (yes) | SE | p * | OR | 95% CI | p ** | |
| Sex | 0.197 | 0.002 | ||||||||||||
| Male | 95 | 7.7 | 1.00 | ref | 148 | 11.7 | 1.18 | ref | ||||||
| Female | 117 | 6.2 | 0.74 | 0.78 | 0.54, 1.14 | 0.198 | 155 | 7.6 | 0.76 | 0.62 | 0.46, 0.85 | 0.003 | ||
| Age, years | 0.584 | 0.954 | ||||||||||||
| 19–24 | 107 | 7.2 | 0.96 | ref | 151 | 9.5 | 1.06 | ref | ||||||
| 25–30 | 107 | 6.6 | 0.78 | 0.90 | 0.62, 1.31 | 0.585 | 157 | 9.5 | 0.89 | 1.01 | 0.74, 1.38 | 0.954 | ||
| College status | 0.277 | 0.456 | ||||||||||||
| Attend a 4‐year college | 35 | 5.6 | 1.15 | 0.77 | 0.48, 1.24 | 0.280 | 57 | 8.5 | 1.34 | 0.87 | 0.59, 1.27 | 0.457 | ||
| Other | 179 | 7.1 | 0.69 | ref | 248 | 9.7 | 0.77 | ref | ||||||
| Race/ethnicity | 0.044 | 0.009 | ||||||||||||
| Non‐Hispanic Black | 13 | 3.1 | 1.06 | 0.43 | 0.21, 0.90 | 0.024 | 16 | 3.7 | 1.10 | 0.35 | 0.19, 0.66 | 0.001 | ||
| Hispanic | 41 | 7.1 | 1.40 | 1.04 | 0.65, 1.66 | 0.882 | 59 | 9.7 | 1.59 | 0.97 | 0.65, 1.45 | 0.890 | ||
| Non‐Hispanic White | 134 | 6.8 | 0.69 | ref | 194 | 10.0 | 0.84 | ref | ||||||
| Multirace/Other race a | 24 | 10.7 | 2.87 | 1.63 | 0.87, 3.05 | 0.127 | 36 | 13.4 | 2.92 | 1.40 | 0.82, 2.36 | 0.215 | ||
| At least one parent has college degree | 0.864 | 0.513 | ||||||||||||
| No | 79 | 6.6 | 0.95 | ref | 111 | 9.0 | 1.09 | ref | ||||||
| Yes | 129 | 6.8 | 0.74 | 1.03 | 0.71, 1.51 | 0.864 | 189 | 9.9 | 0.85 | 1.11 | 0.81, 1.54 | 0.513 | ||
| Year | 0.243 | 0.526 | ||||||||||||
| 2022 | 102 | 6.2 | 0.80 | ref | 142 | 9.1 | 0.96 | ref | ||||||
| 2023 | 112 | 7.6 | 0.93 | 1.25 | 0.86, 1.81 | 0.244 | 166 | 10.0 | 0.97 | 1.11 | 0.81, 1.51 | 0.527 | ||
Abbreviations: CI, confidence interval; OR, odds ratio.
This category included respondents identifying as Asian, multi‐race or another race.
p‐value based on chi‐square test.
p‐value based on logistic regression.
Table 2 shows the substance use correlates of microdosing and any hallucinogen use. All substances analysed were significantly more prevalent among those who reported microdosing compared with those who did not, with the exception of 1 occasion of past two‐week binge drinking compared with no occasions. Significant odds ratios ranged from 2.53 (95% CI 1.43–4.47) for past 30‐day cigarette use vs. none, to 37.73 (95% CI 19.72–72.21) for 3+ occasions of cannabis use in the past year vs. none, among those who reported past‐year microdosing compared with those who did not. For example, the likelihood of 10+ occasions (vs. 0 occasions) of past‐year alcohol use was significantly higher among those who reported microdosing (72.4% vs. 2.4%) than those who did not (44.9% vs. 17.3%); OR 11.82, 95% CI 3.73–37.44. Cannabis use was also highly concentrated in those who microdosed; the likelihood of 3+ occasions of cannabis use in the past year (vs. 0 occasions) was substantially higher among those who microdosed (85.8% vs. 5.3%) than those who did not (27.0% vs. 63.2%), OR 37.73, 95% CI 19.72–72.21.
TABLE 2.
Association between past‐year microdosing and any hallucinogen use with other substance use among young adults aged 19–30 in the United States from 2022 to 2023.
| Microdosing | Any hallucinogen use | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Any use | None | OR | 95% CI | p | Any use | None | OR | 95% CI | p | |||||
| % | SE | % | SE | % | SE | % | SE | |||||||
| Past‐year alcohol use | ||||||||||||||
| 0 occasions | 2.4 | 1.34 | 17.3 | 0.94 | (ref = 0 occasions) | 2.2 | 0.98 | 18.3 | 0.95 | (ref = 0 occasions) | ||||
| 1 to 9 occasions | 25.2 | 3.92 | 37.8 | 1.19 | 4.88 | 1.49, 15.97 | 0.009 | 24.0 | 3.33 | 37.2 | 1.15 | 5.46 | 2.10, 14.20 | 0.001 |
| 10+ occasions | 72.4 | 4.04 | 44.9 | 1.23 | 11.82 | 3.73, 37.44 | < 0.001 | 73.8 | 3.40 | 44.4 | 1.20 | 14.07 | 5.61, 35.31 | 0.001 |
| Past two‐week binge drinking | ||||||||||||||
| None | 51.3 | 4.61 | 72.0 | 1.13 | (ref = none) | 46.3 | 3.81 | 73.6 | 1.07 | (ref = none) | ||||
| Once | 11.3 | 2.21 | 13.3 | 0.84 | 1.19 | 0.74, 1.94 | 0.474 | 18.0 | 3.12 | 12.6 | 0.78 | 2.28 | 1.44, 3.59 | < 0.001 |
| Twice of more times | 37.5 | 4.60 | 14.7 | 0.91 | 3.57 | 2.32, 5.49 | < 0.001 | 35.6 | 3.74 | 13.8 | 0.86 | 4.12 | 2.86, 5.93 | < 0.001 |
| Past year cannabis use (any method) | ||||||||||||||
| 0 occasions | 5.3 | 1.64 | 63.2 | 1.19 | (ref = 0 occasions) | 8.0 | 2.17 | 64.5 | 1.15 | (ref = 0 occasions) | ||||
| 1 to 2 occasions | 8.8 | 2.66 | 9.8 | 0.75 | 10.70 | 4.42, 25.91 | < 0.001 | 8.6 | 2.03 | 10.0 | 0.74 | 6.96 | 3.28, 14.76 | < 0.001 |
| 3+ occasions | 85.8 | 3.04 | 27.0 | 1.09 | 37.73 | 19.72, 72.21 | < 0.001 | 83.3 | 2.84 | 25.5 | 1.04 | 26.26 | 14.56, 47.35 | < 0.001 |
| Past‐year cannabis smoking a | ||||||||||||||
| None | 8.5 | 2.24 | 24.9 | 1.76 | (ref = none) | 11.5 | 2.21 | 26.8 | 1.84 | (ref = none) | ||||
| Any use | 91.5 | 2.24 | 75.1 | 1.76 | 3.56 | 1.97, 6.43 | < 0.001 | 88.5 | 2.21 | 73.2 | 1.84 | 2.80 | 1.76, 4.45 | < 0.001 |
| Past‐year cannabis vaping | ||||||||||||||
| None | 31.4 | 4.35 | 56.6 | 2.08 | (ref = none) | 35.9 | 3.85 | 58.7 | 2.07 | (ref = none) | ||||
| Any use | 68.6 | 4.35 | 43.4 | 2.08 | 2.85 | 1.85, 4.37 | < 0.001 | 64.1 | 3.85 | 41.3 | 2.07 | 2.54 | 1.75, 3.67 | < 0.001 |
| Past‐year other cannabis use methods b | ||||||||||||||
| None | 13.9 | 2.73 | 38.9 | 2.02 | (ref = none) | 19.6 | 2.90 | 40.8 | 2.06 | (ref = none) | ||||
| Any use | 86.1 | 2.73 | 61.1 | 2.02 | 3.93 | 2.44, 6.34 | < 0.001 | 80.4 | 2.90 | 59.2 | 2.06 | 2.83 | 1.90, 4.22 | < 0.001 |
| Past 30‐day cigarette use | ||||||||||||||
| None | 82.3 | 4.00 | 92.2 | 0.69 | (ref = none) | 79.0 | 3.39 | 92.0 | 0.68 | (ref = none) | ||||
| Any use | 17.4 | 4.00 | 7.8 | 0.69 | 2.53 | 1.43, 4.47 | < 0.001 | 21.0 | 3.39 | 8.0 | 0.68 | 3.07 | 1.98, 4.76 | < 0.001 |
| Past‐year nicotine vaping | ||||||||||||||
| None | 35.5 | 4.48 | 77.8 | 1.03 | (ref = none) | 35.6 | 3.66 | 78.4 | 0.99 | (ref = none) | ||||
| Any use | 64.5 | 4.48 | 22.2 | 1.03 | 6.40 | 4.28, 9.55 | < 0.001 | 64.4 | 3.66 | 21.6 | 0.99 | 6.55 | 4.69, 9.14 | < 0.001 |
| Past‐year other drug use c | ||||||||||||||
| None | 56.5 | 4.50 | 92.8 | 0.67 | (ref = none) | 58.5 | 3.71 | 93.4 | 0.62 | (ref = none) | ||||
| Any use | 43.5 | 4.50 | 7.2 | 0.67 | 9.90 | 6.58, 14.91 | < 0.001 | 41.5 | 3.71 | 6.7 | 0.62 | 9.99 | 6.98, 14.30 | < 0.001 |
Abbreviations: CI, confidence interval; OR, odds ratio.
Smoking methods of cannabis use include smoking a joint, smoking a blunt, smoking in a bong/water pipe and smoking in another type of pipe.
Other methods of cannabis use include eating in food, drinking in a beverage, using a concentrate (such as ‘wax’, ‘budder’ or ‘shatter’) and other methods.
Other drug use defined as any 12‐month amphetamine use, 12‐month cocaine use or 12‐month tranquilliser use.
Also shown in Table 2 are the substance use correlates of any hallucinogen use. The magnitude and range of prevalence and odds ratios were similar to those for microdosing, with odds ratios ranging from 2.28 (95% CI 1.44–3.59) for 1 occasion of past two‐week binge drinking vs. none to 26.26 (95% CI 14.56–47.35) for 3+ occasions of cannabis use in the past year vs. none among those who reported past‐year hallucinogen use compared with those who did not.
4. Discussion
The present study demonstrates in a national sample of young adults that instances of microdosing hallucinogens are prevalent, with approximately 1 in 15 young adults, and 2 in 3 young adults who used hallucinogens reporting at least one past‐year incident of microdosing. Those who report microdosing represent a group in which other substance use is also concentrated, with a large majority reporting 10+ occasions of alcohol and cannabis use as well as nicotine vaping, as well as higher odds of other drug use. Both demographic and other substance use correlates were similar between those who used any hallucinogens and those who microdosed, indicating that microdosing has a similar profile as has been previously demonstrated for hallucinogen use more generally. Further, these results underscore that while the safety and health consequences of microdosing remain understudied, those who microdose are at higher risk for adverse health outcomes given that substance use with known adverse health consequences frequently co‐occur.
Despite growing interest in microdosing for purported benefits, including enhanced creativity and improved mood, rigorous scientific evidence supporting these claims remains limited [4, 5]. Hallucinogens commonly used for microdosing such as psilocybin remain Schedule I controlled substances, indicating no accepted medical use and high potential for abuse [14, 15]. Research on potential therapeutic uses of hallucinogens for conditions such as post‐traumatic stress disorder, depression and anxiety, and addiction has broadly demonstrated initial efficacy [11, 16], though there may be variation in doses and protocols often include higher doses than the amounts consumed in microdosing [17]. However, small sample sizes, inconsistent control conditions, inability to isolate pharmacological effects in the context of intensive psychological support and limited long‐term data remain challenges to understanding potential benefits [15, 16]. Fourteen randomised blinded controlled trials of microdosing protocols have been conducted with small sample sizes, and results indicate modest increases in mood enhancement, although elevation in anxiety as well [18]. Thus, the clinical utility of microdosing remains relatively unknown, and future research with robust randomised designs specifically focused on microdosing regimens would be a valuable addition to the field.
Our findings raise concerns about the substantially higher rates of polysubstance use among those who microdose. While some research suggests microdosing may have therapeutic potential for psychiatric and substance use disorders, high levels of other substance use may reduce any potential health benefits. It has long been demonstrated that use of different psychoactive substances is correlated (including that individuals who use psychedelics frequently use other substances as well [19]), given that individuals who use substances may be more open to experimenting with a variety of products and may be more likely to be in situations where multiple products are available. We demonstrate here that these well‐documented correlations are also apparent for those who microdose hallucinogens, although it is important to note that we did not have data on simultaneous use of microdosing with other substances. Nevertheless, in the context of recent policy changes in select US jurisdictions to decriminalise hallucinogen possession and use [20], continued surveillance of hallucinogen use and correlations with other drug use remains pertinent as availability potentially increases.
Several limitations of this study should be noted. First, data are self‐reported, which may be subject to recall bias and misunderstandings of questions, including that respondents may not accurately report or know whether their dosage was a ‘microdose’ of hallucinogens. Second, the MTF survey did not query frequency, pattern, timing, duration or motivation for microdosing. Associations were based on concurrent reports of recent drug use and there were no data on the extent to which substances were used simultaneously, precluding assessment of temporality regarding the relationship between microdosing and other substance use patterns. While this is a significant limitation, MTF is also the only nationally representative survey of drug use that queries microdosing, thus the unique addition to the survey is a strength. Nevertheless, concentrated epidemiological research on microdosing patterns is needed. Third, these data are based on young adult longitudinal follow‐ups of participants initially surveyed in high school; thus, those who dropped out of high school are not included and differential attrition presents a challenge to generalisability. Further, while our sample size, close to 3000 respondents, is among the largest for longitudinal studies of drug use ongoing in the United States, sample sizes were small for some subgroups (e.g., those who both report microdosing and high levels of other drug use) resulting in wide confidence intervals for some comparisons; additional research, including with MTF data as we accumulate more cohorts, is needed to confirm patterns observed here.
In summary, this national study provides the first epidemiological evidence on microdosing hallucinogen prevalence among young adults in the United States, with approximately 1 in 15 reporting past‐year use, and demonstrates that microdosing is strongly associated with polysubstance use patterns that warrants further investigation. Microdosing is an understudied practice, and polysubstance associations highlight the need for comprehensive approaches to substance use prevention and education that address microdosing of hallucinogens within broader patterns of polysubstance use.
Funding
This work was supported the National Institute on Drug Abuse (R01DA016575, R01DA001411).
Conflicts of Interest
The authors declare no conflicts of interest.
Supporting information
Table S1: Sample demographics and missing data patterns for the participants queried about any past‐year hallucinogen use (total possible N = 3094) and past‐year microdosing (total possible N = 2860) among young adults aged 19–30 in the United States from 2022 to 2023.
Author Contributions
KM Keyes conceptualised the study, supervised data analyses and drafted the paper. Y Terry‐McElrath conducted data analysis and provided critical revisions to the paper. M. Patrick conceptualised the study, supervised data analyses and drafted the paper.
Acknowledgements
The authors would like to thank Shanna Rogan for her assistance with data management and analysis.
Data Availability Statement
Data are available through the National Addition and Health Data Archive Program at: https://www.icpsr.umich.edu/sites/nahdap/home.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Table S1: Sample demographics and missing data patterns for the participants queried about any past‐year hallucinogen use (total possible N = 3094) and past‐year microdosing (total possible N = 2860) among young adults aged 19–30 in the United States from 2022 to 2023.
Data Availability Statement
Data are available through the National Addition and Health Data Archive Program at: https://www.icpsr.umich.edu/sites/nahdap/home.