International Journal of Drug Policy 75 (2020) 102600

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International Journal of Drug Policy

journal homepage: www.elsevier.com/locate/drugpo

Research Paper

Microdosing psychedelics: Motivations, subjective effects and harm T

reduction
Toby Leaa,b,⁎, Nicole Amadac, Henrik Jungaberled, Henrike Scheckee, Michael Kleina
a
German Institute for Addiction and Prevention Research, Catholic University of Applied Sciences, Wörthstr. 10, 50668 Cologne, Germany
b
Centre for Social Research in Health, UNSW, Sydney, NSW 2052, Australia
c
The Graduate Center, City University of New York, 365 5th Ave, New York, NY 10016, USA
d
MIND Foundation, Betahaus Berlin, Rudi-Dutschke-Straße 23, 10969 Berlin, Germany
e
Department of Psychiatry and Psychotherapy, Faculty of Medicine, University of Duisburg-Essen, LVR-Klinikum Essen, Virchowstr. 174, 45147 Essen, Germany

ARTICLE INFO ABSTRACT

Keywords: Background: In recent years there has been growing media attention on microdosing psychedelics (e.g., LSD,
Microdose psilocybin). This refers to people routinely taking small doses of psychedelic substances to improve mental
LSD health and wellbeing, or to enhance cognitive performance. Research evidence is currently limited. This paper
Psilocybin examines microdosing motivations, dosing practices, perceived short-term benefits, unwanted effects, and harm
Mental health
reduction practices.
Cognition
Treatment
Methods: An international online survey was conducted in 2018 examining people's experiences of using psy-
chedelics. Eligible participants were aged 16 years or older, had used psychedelics and could comprehend
written English. This paper focuses on 525 participants who were microdosing psychedelics at the time of the
survey.
Results: Participants were primarily motivated to microdose to improve mental health (40%), for personal de-
velopment (31%) and cognitive enhancement (18%). Most were microdosing with psilocybin (55%) or LSD/1P-
LSD (48%). Principal components analysis generated three factors examining perceived short-term benefits of
microdosing: improved mood and anxiety, enhanced connection to others and environment, and cognitive en-
hancement; and three factors examining negative and potentially unwanted effects: stronger-than-expected
psychedelic effects, anxiety-related effects, and physical adverse effects. Most participants (78%) reported at
least one harm reduction practice they routinely performed while microdosing.
Conclusion: Our findings suggest that people microdosing are commonly doing so as a self-managed therapy for
mental health, either as an alternative or adjunct to conventional treatments. This is despite psychedelics re-
maining prohibited substances in most jurisdictions. Recent findings from clinical trials with standard psyche-
delic doses for depression and anxiety suggest that a neurobiological effect beyond placebo is not unreasonable.
Randomised controlled trials are needed, complemented by mixed methods social science research and the
development of novel resources on microdosing harm reduction.

Introduction in terminally ill patients (Gasser et al., 2014; Griffiths et al., 2016;
Liechti, 2017). Administered on a small number of occasions in a
Over the past decade, there has been renewed interest in the use of therapeutic setting, phase II studies have shown positive results and few
psychedelics to treat mental and substance use disorders, leading to adverse effects (Nichols, 2016; Reiche et al., 2018). The US Food and
clinical trials of psilocybin and ayahuasca for treatment-resistant de- Drug Administration has recently granted psilocybin “breakthrough
pression (Carhart-Harris et al., 2018; Palhano-Fontes et al., 2019), therapy” designation to expedite its clinical development and review,
psilocybin for alcohol dependence (Bogenschutz et al., 2015) and ni- which could lead to psychedelic therapy as a legally available treatment
cotine dependence (Johnson, Garcia-Romeu & Griffiths, 2017), and for some mental disorders in the next decade (COMPASS Pathways,
psilocybin and lysergic acid diethylamide (LSD) for end-of-life anxiety 2018).

⁎
Corresponding author at: German Institute for Addiction and Prevention Research, Catholic University of Applied Sciences, Wörthstr. 10, 50668 Cologne,
Germany.
E-mail address: toby.lea@unsw.edu.au (T. Lea).

https://doi.org/10.1016/j.drugpo.2019.11.008

0955-3959/ © 2019 Elsevier B.V. All rights reserved.

T. Lea, et al. International Journal of Drug Policy 75 (2020) 102600

Coinciding with the resurgence of clinical psychedelic research, survey examining practices and subjective experiences of using psy-
“microdosing” has gained considerable media attention in recent years. chedelic substances at standard doses and microdoses. Recruitment was
Microdosing refers to the ingestion of low to very low doses of psy- conducted in late 2018 via email lists of psychedelic communities and
chedelics (typically between 5 and 10 percent of a standard dose) on a non-profit organisations (e.g., The Third Wave, microdosing.nl), posts
routine schedule (e.g., every third day) without the intention of ex- on online discussion forums (e.g., microdosing subreddit, shroomer-
periencing noticeable drug effects (Fadiman, 2011; Kuypers et al., y.org), shared Facebook posts via these organisations and psychedelic
2019; Liechti, 2019). Although a recent randomised controlled trial societies in different countries, and paid Facebook advertisements.
reported 13mcg of LSD as a threshold microdose (Bershad, Schepers, People were eligible to participate in the study if they were 16 years or
Bremmer, Lee, & de Wit, 2019), there is currently no scientific con- older, had used psychedelics for any purpose and could comprehend
sensus about what dose ranges constitute LSD and psilocybin micro- written English. Participants received no remuneration. This research
doses (Kuypers et al., 2019; Passie, 2019). News and popular media was approved by the Faculty of Medicine Ethics Committee, University
articles have described it as a workplace trend, first reported among of Duisburg-Essen, Germany (Ref: 18-8215-BO).
technology professionals in Silicon Valley who microdosed as a cogni- We recruited 2674 participants, including 1533 who had micro-
tive “biohack” to enhance productivity, focus and creative problem- dosed psychedelics and completed questions on microdosing practices
solving (Dean, 2017; Glatter, 2015). Perhaps driven to some extent by and motivations. This paper is focused on participants who were mi-
the promising findings of clinical research with larger doses, there have crodosing at the time of the survey (n = 525; 34.2% of those who re-
also been increasing reports of people microdosing as a self-managed ported microdosing).
treatment for depression, anxiety and other mental disorders (Hutten,
Mason, Dolder & Kuypers, 2019; Waldman, 2017). Measures
While some research on small LSD doses was conducted before
psychedelics were banned in the USA in 1970 (Passie, 2019), con- Participants were asked about the substances they had microdosed,
temporary research on microdosing is in its infancy. Two recent ran- dosing schedules, duration of microdosing, dose adjustment, obtaining
domised controlled trials of LSD microdosing have shown changes in psychedelics, knowledge sources and disclosure of microdosing to dif-
time perception following LSD administration (Yanakieva et al., 2019), ferent groups (e.g., friends, health professionals). Some items about
and dose-related increases in ratings of “vigor” (Bershad, Schepers, microdosing practices were asked separately for psilocybin, LSD and
Bremmer, Lee, & de Wit, 2019). A naturalistic experimental study found 1P-LSD (an LSD analogue), and N,N-Dimethyltryptamine (DMT), in-
improved performance on problem-solving tasks after taking a non- cluding dose, preparation and administration.
blinded microdose of psilocybin truffles (Prochazkova et al., 2018). In The Severity of Dependence Scale (SDS) measured potential adverse
addition, observational online studies have reported improved mood, consequences of psychedelic use (Gossop et al., 1995), acknowledging
wellbeing and cognitive performance on days when a microdose is in- that psychedelic use is generally not associated with dependence
gested (Anderson et al., 2019; Fadiman & Korb, 2019; Politi & (Nichols, 2016; Nutt, King & Phillips, 2010). The SDS includes 5 items
Stevenson, 2019), and fewer symptoms of depression and stress after six and the total score ranges from 0 to 15. We reported mean scores and
weeks of microdosing (Politi & Stevenson, 2019). An online interview used a cut-off score of ≥4 to indicate potential problems with use
study reported perceived improvements in mood and creativity with (Bruno et al., 2009).
few adverse effects (Johnstad, 2018), while another qualitative study Short-term perceived benefits of microdosing were examined with
reported that interviewees rationalised microdosing as a functional 22 items (yes, no). Participants were asked to select items that they
form of drug use akin to taking a supplement, in order to be “the best usually experienced when microdosing (i.e., on more than 50% of days
possible version of themselves” (Webb, Copes & Hendricks, 2019, p. that they microdosed). Negative and other potentially unwanted effects
35). experienced on days when participants microdosed in the past 12
People are motivated to use psychedelics at standard doses for a months were examined with 23 items using a 5-point Likert scale
range of reasons including to enhance pleasure, as treatments for (never, rarely, sometimes, often, always). Harm reduction and other
mental and physical health concerns, for self-exploration and devel- practices usually performed or avoided when microdosing (on more
opment, and spiritual growth (Móró, Simon, Bárd & Racz, 2011; than 50% of microdosing days) were examined with 20 items (yes, no).
Prepeliczay, 2002). At standard doses, LSD and psilocybin induce en- For each of these three sections, items were designed by the researchers
during improvements in mood and well-being, positive attitudes to- based on previous psychedelic and harm reduction research and a
wards life, social connectedness and empathy, according to self-report, content analysis of online microdosing discussion forums (Lea, Amada
irrespective of their motivations for use (Carhart-Harris et al., 2016; & Jungaberle, 2019). Items in each section were presented in random
Lerner & Lyvers, 2006; Schmid & Liechti, 2018; Watts, Day, order.
Krzanowski, Nutt & Carhart-Harris, 2017). While much has been pub-
lished about harm reduction practices among MDMA users – with Statistical analyses
MDMA categorised as a stimulant or entactogen – relatively little has
been published about psychedelic harm reduction (Allott & Redman, Data were analysed using Stata (v13.0) and statistical significance
2006; Bøhling, 2017; Global Drug Survey, 2015; Van Schipstal, Mishra, was set at p<0.05. We compared participants who were currently mi-
Berning & Murray, 2016). crodosing exclusively using LSD/1P-LSD with those exclusively using
This paper aims to describe the motivations, dosing practices, short- psilocybin using t-tests and chi-square tests for sociodemographic
term perceived benefits and unwanted effects, and harm reduction characteristics, psychedelic use history, microdosing motivations,
practices of people microdosing psychedelics. A secondary aim was to dosing practices, perceived benefits, unwanted effects, and harm re-
determine whether different microdosing motivations and microdosed duction practices.
substances were associated with perceived benefits and unwanted ef- A proportion of respondents did not complete items on unwanted
fects. effects and harm reduction practices. We conducted a sensitivity ana-
lysis to compare the sociodemographic characteristics of respondents
Methods who completed these questions (n = 467) with those who did not
(n = 58). No significant differences were detected.
Sample and recruitment We conducted two principal component analyses using polychoric
correlation matrices to determine whether items about (1) short-term
The Psychedelic Experiences Survey is an international online benefits from microdosing and (2) unwanted effects of microdosing

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T. Lea, et al. International Journal of Drug Policy 75 (2020) 102600

formed reliable scales. Polychoric methods are appropriate when con- participants reported microdosing for personal and spiritual develop-
ducting factor analyses with binary and ordinal scales (Flora & Curran, ment (31.2%) and to enhance cognitive performance at work or study
2004). The minimum loading for inclusion on a factor was 0.4. If an (18.1%).
item loaded on two factors, a difference of at least 0.2 between loadings Fifty-five percent of participants were currently microdosing with
was required to include the higher loading item. For scales generated psilocybin mushrooms or truffles, 48.2% with LSD/1P-LSD, 3.0% with
from factors for short-term benefits, scale scores ranged from 0 (no DMT, and 3.0% with other psychedelics (Table 1). The most common
items endorsed) to 1 (all items endorsed), and for unwanted effects, dosing schedule was one day microdosing and two days off on a re-
scale scores ranged from 0 (never) to 4 (always). We used multivariate peated cycle (31.8%), and most participants microdosed in the morning
linear regression to examine differences in mean scores on each scale (72.0%).
between participants microdosing LSD/1P-LSD only and participants Among participants microdosing with psilocybin (n = 287), 19.9%
microdosing psilocybin only, and according to participants primary were microdosing up to 0.1 g of mushrooms or truffles, 26.8% from
motivation for microdosing, controlling for potentially confounding 0.11 to 0.2 g, 22.6% from 0.21 to 0.35 g, 13.9% from 0.36 to 0.5 g,
variables (age, gender, education, employment, country of residence, 12.2% more than 0.5 g, and 4.5% did not know their dose in grams.
taken standard psychedelic dose in past year). Regression results report Participants most commonly prepared microdoses by cutting dried
standardised betas. Harm reduction practices were not examined via mushrooms/truffles into small pieces (29.6%), putting ground mush-
principal component analysis as several items were not applicable to all rooms/truffles into capsules (22.0%), or grinding mushrooms/truffles
participants (e.g., avoiding antidepressants on microdosing days). to a powder (20.9%). A minority reported taking pre-ground (5.2%) or
pre-encapsulated mushrooms/truffles (3.8%) or cutting up fresh
Results mushrooms/truffles (3.5%). The majority of participants measured
their microdoses with electronic scales (59.6%), and the remainder
Sample characteristics measured microdoses by sight (16.0%), with kitchen scales (1.7%), a
measuring cup or spoon (1.4%) or an undisclosed method (21.3%).
The mean age of the 525 participants was 34.5 years (SD = 12.7). Among participants who were microdosing with LSD/1P-LSD
The majority of participants were men (73.5%), identified as hetero- (n = 253), the mean microdose was 13 micrograms (SD = 7.5;
sexual (78.3%), had completed a university degree (52.8%) and were in median = 10; range 0–50). Half of participants used volumetric dosing
a relationship (55.4%). Half of participants were in full-time employ- to prepare microdoses (49.8%; i.e., diluting a blotter tab in liquid to
ment (49.3%), 15.4% were in part-time employment and 17.3% were extract the LSD), 36.4% cut each tab into pieces, 8.3% used liquid LSD
students. Almost half of participants resided in the United States (which they diluted themselves or purchased diluted), and 5.5% did
(48.2%), with smaller numbers from the United Kingdom (7.4%), something else (e.g., used lower strength tabs). Among participants
Canada (6.7%), Germany (5.0%), Australia and New Zealand (4.6%), who volumetrically dosed (n = 126), 45.2% diluted their LSD in al-
and the Netherlands (3.8%). Remaining participants resided in cohol (most often vodka, 35.7%), 33.3% in distilled or demineralised
Southern/Eastern Europe (12.0%), other parts of Western/Northern water, 11.9% in tap or spring water and 9.5% in another liquid. Thirty-
Europe (8.8%), Middle East or Africa (1.7%), Central and South three percent of participants diluted each standard dose tab in 5–10 ml
America (1.3%), and Asia (0.6%). Compared to participants micro- of liquid, 28.0% in 15–50 ml and 39.2% in over 50 ml. Thirty-eight
dosing with LSD/1P-LSD, participants microdosing with psilocybin percent of participants waited up to 24 h for the LSD to extract before
were older (M = 36.7 vs. M = 31.5, p<.001), more likely to be female taking a dose, 36.8% waited 25–48 h, and 25.6% waited over 48 h.
(30.2% vs. 17.5%, p = .004) and live in the US (59.9% vs. 35.8%, Most participants measured each microdose with an oral syringe
p<.001), and less likely to be a student (12.4% vs. 24.5, p = .01). (46.8%) or an eye dropper (30.2%), and the remainder used a small
Twenty-two percent of participants were recruited via The Third Wave, measuring cup or spoon (9.5%), by sight (5.6%) or some other method
19.8% via Facebook/Instagram, 19.4% via Reddit, 8.8% via (7.9%).
Shroomery.org and 4.2% via other psychedelic organisations and Among the 16 participants microdosing DMT, the median dose was
forums. Twenty-six percent did not report where they heard about the 8–9 milligrams. Nine participants measured their dose with electronic
study. scales and 6 participants by sight. Ten participants administered DMT
Sixty-five percent of participants had ever taken a standard (“full”) with a vape pen or pipe and 3 smoked Changa (DMT-infused smoking
dose of psychedelics for self-reported “therapeutic” purposes; 53.3% in blend).
the past 12 months. Sixty-seven percent of participants had used stan- Among all participants, more than two-thirds (70.3%) reported in-
dard psychedelic doses for recreational purposes; 47.8% in the past 12 itially adjusting their microdose through trial and error, and over a
months. Fifty-four percent of participants used psychedelics re- third (35.6%) reported having to readjust their dose at least some of the
creationally at a younger age than when they first microdosed, 10.3% time with each new batch of psychedelics obtained (Table 1). Sixty-nine
were the same age when they first microdosed and used psychedelics percent of participants reported sometimes taking a higher than normal
recreationally, and 2.9% were younger when they microdosed. microdose, either accidentally or intentionally. Few participants (2.5%,
Forty-three percent of participants had ever been diagnosed with a n = 13) reported SDS scores suggestive of an elevated risk of experi-
mental disorder, 49.3% had seen a psychotherapist for their mental encing adverse consequences from psychedelic use.
health, 34.3% had been prescribed psychiatric medication, and 10.5% Most participants (70.9%) learned about microdosing via psyche-
had accessed alcohol and other drug treatment. delic information and harm reduction websites and online forums, and
via podcasts, YouTube videos, and other online forums for people who
Microdosing practices use drugs. Most participants had told friends or their partner they were
microdosing (90.3%), and a minority had discussed microdosing with
The mean age of commencing microdosing was 31 years, and par- their doctor, psychiatrist/therapist (if applicable), or another health
ticipants microdosing with psilocybin were older on commencement professional (17.9%; Table 1).
than those microdosing with LSD/1P-LSD (34 vs. 29 years, p<.001;
Table 1). Most participants had been microdosing for 6 months or less Perceived short-term microdosing benefits
(65.0%). The most common primary motivation for microdosing was to
address issues with mental health or substance use (40.4%), which was Principal components analysis resulted in three reliable scales of
more commonly reported among participants microdosing with psilo- perceived benefits participants usually experienced on days they mi-
cybin than with LSD/1P-LSD (47.1% vs. 32.1%, p = .001). Other crodosed (i.e., more than 50% of the time; Table 2). This included

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T. Lea, et al. International Journal of Drug Policy 75 (2020) 102600

Table 1
Microdosing practices among participants currently microdosing, and comparing participants currently microdosing only with LSD/1P-LSD or only with psilocybin.
Currently microdosing (%)
All participants (%) LSD / 1P-LSD only (n = 212) Psilocybin only
(n = 525) (n = 242)

Age at first microdose (M, SD) 31.4 (12.6) 29.4 (11.8) 33.6 (12.7)***
Total microdosing duration
Less than 1 month 18.5 19.8 19.4
1–2 months 21.0 20.3 24.0
3–6 months 25.5 29.2 24.0
7–12 months 10.7 9.9 12.0
1–2 years 10.7 10.4 9.5
More than 2 years 13.7 10.4 11.2
Primary motivation for microdosing *
Depression 24.4 18.9 31.0
Anxiety 7.4 5.2 9.1
Other mental health 6.5 7.1 5.8
Substance use cessation / reduction 2.1 0.9 1.2
Physical health 1.9 1.4 2.5
Wellbeing and personal development 31.2 33.5 27.7
Cognitive enhancement 18.1 22.2 16.5
Curiosity 8.4 10.8 6.2
Substances microdosed Ever Current Ever Current Ever Current
Psilocybin mushrooms 65.9 51.2 29.7 – 94.2 93.8
Psilocybin truffles 9.0 4.2 7.1 – 9.1 6.6
LSD 54.9 40.4 84.0 82.1 24.0 –
1P-LSD 12.4 8.4 21.7 17.9 2.5 –
DMT 11.2 3.0 8.5 – 6.6 –
Mescaline 5.3 1.0 2.4 – 2.9 –
Ayahuasca 4.0 0.8 1.9 – 1.7a –
4-AcO-DMT 3.6 0.8 2.8 – 1.2a –
Ibogaine 2.3 0.6 0.9 – 0.8a –
Other psychedelics (e.g., 2C-B, ALD-52, 4-HO-MET) 4.6 0.0 3.3 – 2.9 –
Currently microdosing more than one psychedelic 9.7 0.0 0.4
Microdosing schedule ***
Every day 6.3 2.4 7.9
Every second day 7.8 4.7 11.6
Every 3 days (1 day on/2 days off) 31.8 36.8 30.6
Every 4 days (1–2 times a week) 21.1 26.4 18.6
Once a week 14.5 16.0 12.4
Once a fortnight 3.4 3.3 1.7
Five days on/2 days off 3.4 0.5 6.2
Flexible schedule/as needed 4.0 4.2 2.9
Something else 7.6 5.7 8.3
Microdose usually taken… ***
Morning 72.0 83.0 65.7
Midday 13.9 10.4 17.4
Afternoon 5.1 3.3 7.0
Evening or before bed 9.0 3.3 9.9
Needed to adjust dose to get it right after commencing microdosing
Yes 70.3 73.6 68.6
No 29.7 26.4 31.4
Need to readjust dose with each new batch of psychedelics obtained
Always 3.2 3.8 3.3
Often 5.3 6.1 6.2
Sometimes 27.0 20.3 30.6
Rarely 21.0 25.9 16.1
Never 43.4 43.9 43.8
Severity of Dependence Scale (M, SD) 0.5 (1.0) 0.6 (1.1) 0.4 (0.8)
Difficulty obtaining psychedelics
Very difficult 4.8 3.3 5.8
Somewhat difficult 24.8 25.0 25.2
Neither difficult nor easy 19.4 22.6 16.9
Somewhat easy 21.1 25.0 19.4
Very easy 39.9 24.1 32.6
Believe quality of psychedelics obtained consistent over time
Yes 65.7 60.4 68.6
No 8.6 8.5 8.3
Unsure 25.7 31.1 23.1
Where learnt how to microdose
Psychedelic websites and online communities/podcasts/Youtube 70.9 75.5 71.1
Online news/internet search 37.1 38.7 38.8
Books and media by psychedelic experts 36.8 34.0 40.1
Friends and other known people 31.4 34.9 27.3
Self-experimentation 4.8 1.9 5.8*
Health professional 3.8 1.9 4.1
Told people you are microdosing
(continued on next page)

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T. Lea, et al. International Journal of Drug Policy 75 (2020) 102600

Table 1 (continued)

Currently microdosing (%)

All participants (%) LSD / 1P-LSD only (n = 212) Psilocybin only
(n = 525) (n = 242)

Friends or partner 90.3 89.2 91.8

Family members 40.4 33.5 43.0*
Work colleagues 22.5 17.9 23.6
Employer 7.2 4.7 7.5
Therapist/counsellor 11.2 10.4 12.4
General practitioner/doctor 8.2 8.0 7.0
Psychiatrist 4.4 3.3 5.0
Any health professional 17.9 16.0 18.6
Number of other microdosers known
None 25.3 28.8 26.0
1–2 32.8 34.9 32.2
3–5 25.5 22.2 30.2
6–10 7.6 5.7 6.2
More than 10 8.8 8.5 5.4

⁎
p<.05; ⁎⁎p<.01; ⁎⁎⁎p<.001.
a
Statistical comparisons not made due to small cell counts (<5).
2C-B=2,5-dimethoxy-4-bromophenethylamine; 4-AcO-DMT=4-Acetoxy-N,N-dimethyltryptamine; 4-HO-MET=4-Hydroxy-N-methyl-N-ethyltryptamine; ALD-
52=1-Acetyl-N,N-diethyllysergamide; DMT=dimethyltryptamine.

improved mood and anxiety, comprising 8 items (α = 0.85; M = 0.56, significant in the multivariate analysis (β = 0.06, p = .19)
SD = 0.35), enhanced connection to people and environment, com- Participants microdosing LSD/1P-LSD reported a higher mean than
prising 5 items, (α = 0.80; M = 0.52, SD = 0.37), and enhanced participants microdosing psilocybin on the enhanced cognitive and
cognitive and other performance, comprising 5 items (α = 0.78; other performance scale (M = 0.47 vs. M = 0.37; β = 0.13, p = .008),
M = 0.42; SD = 0.36). In multivariate analyses, higher means on the as did participants motivated to microdose for cognitive enhancement
improved mood and anxiety scale were reported among participants (M = 0.48; β = 0.18, p = .015). Secondary analyses showed no sta-
microdosing as a treatment for depression (M = 0.62; β = 0.26, tistically significant associations between dose level and mean scale
p = .001), anxiety (M = 0.64; β = 0.19, p = .002) and other mental scores.
health conditions (M = 0.68; β = 0.18, p = .002). While high mean
scores on this scale were also reported among participants microdosing
to cease or reduce substance use (M = 0.78), this was not statistically

Table 2
Perceived benefits usually experienced on microdosing days (i.e., on more than 50% of days that participants microdosed).
All participants (%) (n = 525) LSD/1P-LSD only (n = 212) Psilocybin only Factor loading
(n = 242)

1. Improved mood and anxiety (Eigenvalue = 5.92; variance = 30.5%; α = 0.85).

Less depressed than usual 60.8 59.9 62.4 .55
Feel more self-confident/comfortable within myself 60.4 62.7 56.2 .62
Clearer mind than usual 60.0 62.3 55.4 .58
Less stressed than usual 55.6 50.9 57.9 .77
More patient than usual 53.3 50.0 54.5 .73
Calmer than usual 53.1 50.0 52.5 .67
Less anxious than usual 52.6 49.5 53.3 .74
Less irritable than usual 51.0 47.2 52.1 .80
2. Enhanced connection to people and environment (Eigenvalue = 5.40; variance = 27.8%; α = 0.80).
Feel more connected to nature and other living things 59.4 59.4 55.8 .88
Enhanced senses (e.g., sight, hearing, taste) 55.2 58.0 52.9 .58
More empathetic than usual 54.5 57.5 50.8 .69
Feel more connected to other people 54.5 52.4 52.1 .64
Heightened spiritual experiences 38.1 33.0 36.8 .83
3. Enhanced cognitive and other performance (Eigenvalue = 4.80; variance = 24.7%; α = 0.78).
Easier to get “in the zone” 47.8 50.0 45.9 .69
Work becomes more fun 46.7 52.4 40.9* .65
More stamina/energy than usual 46.5 54.7 38.4** .66
Better at solving problems 43.2 47.2 38.4 .67
Better athletic performance/physical capability 27.8 30.7 22.3* .63
Loaded on more than one factor
Happier than usual 65.0 66.5 62.4 –
Feel more connected to myself 59.2 60.4 55.8 –
Higher level of focus/concentration than usual 57.7 60.8 53.7 –
More creative than usual 54.1 57.1 50.0 –
Enjoy/appreciate music more 50.3 56.1 42.6** –
Enjoy sex more/have better sex 26.5 30.7 19.0** –
Enjoy/appreciate food more 22.7 19.8 21.9 –

⁎
p<.05; ⁎⁎
p<.01; p<.001.
⁎⁎⁎

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T. Lea, et al. International Journal of Drug Policy 75 (2020) 102600

Table 3
Negative and other potentially unwanted effects experienced on days when microdosing in the past 12 months.
All participants (n = 467) LSD/1P-LSD only Psilocybin only (n = 216)
(n = 187)
Ever (%) Often or Ever (%) Ever (%) Factor loading
Always (%)

1. Psychedelic effects (Eigenvalue = 3.52; variance = 36.2%; α = 0.72)

Euphoria 79.2 22.3 80.7 76.9 .56
Feel like you are mildly “tripping” 70.7 7.1 72.7 68.5 .69
Altered sense of time and space 52.9 8.4 54.5 47.7 .66
Dilated/enlarged pupils 40.9 7.3 43.9 36.1 .61
Hallucinations or visual distortions 37.7 2.4 36.9 33.8 .74
2. Anxiety effects (Eigenvalue = 3.50; variance = 35.9%; α = 0.72)
Difficulty concentrating 49.9 1.9 56.7 46.8* .52
Anxiety 44.8 2.1 43.9 45.8 .76
Feeling overwhelmed 37.3 1.9 44.9 30.6** .59
Unwanted thoughts, emotions or memories 36.6 2.6 34.2 38.4 .65
Irritability 35.1 1.5 36.4 34.7 .56
Paranoia 21.4 0.2 19.8 21.3 .55
3. Physical effects (Eigenvalue = 1.82; variance = 18.7%; α = 0.56)
Trouble sleeping 45.0 3.2 52.4 36.6** .43
Overstimulated at end of day 43.3 3.2 54.5 33.3*** .43
Headache 26.8 1.9 34.8 20.4** .61
Muscle or joint pain/stiffness 21.4 2.1 26.2 18.1* .65

Loaded on no factor or more than one factor

Vivid dreams 69.4 19.7 62.0 71.8* –
Feeling sick in the stomach 32.5 2.8 28.3 35.6 –
Fast or irregular heartbeat 32.3 2.1 36.9 28.7 –
Feeling disoriented 31.1 0.6 35.5 28.7 –
Confusion 24.2 0.6 27.3 22.2 –
Loss of sense of self 20.3 2.1 20.9 19.0 –

⁎
p<.05; ⁎⁎
p<.01; p<.001.
⁎⁎⁎

Unwanted microdosing effects Discussion

Principal components analysis retained three factors about negative This study examined motivations, practices and subjective experi-
and other potentially unwanted effects ever experienced on days when ences of microdosing psychedelics in an international online sample.
participants had microdosed in the past 12 months (Table 3). The scales Almost all participants were microdosing psilocybin (55%) or LSD
included potentially unwanted psychedelic effects (5 items, α = 0.72; (48%), most had been microdosing for up to six months (65%), and a
M = 0.99, SD = 0.68), anxiety effects (6 items, α = 0.72; M = 0.51, diverse range of motivations and dosing practices were reported. The
SD = 0.48), and unpleasant physical effects (4 items, α = 0.56; most common motivation for microdosing was an alternative treatment
M = 0.52, SD = 0.52). There were differences between participants for mental health (40%), either as a replacement or adjunct to con-
microdosing psilocybin and LSD/1P-LSD on the physical effects scale, ventional treatments, followed by personal development and general
with a higher mean reported among participants using LSD/1P-LSD wellbeing (31%), and enhancement of cognitive function (18%). Most
(M = 0.68 vs. M = 0.38, β = 0.30, p<.001). While there were no participants reported experiencing benefits on microdosing days, in-
differences for psilocybin and LSD/1P-LSD on the anxiety scale, parti- cluding improved mood and reduced anxiety, greater connection to
cipants microdosing LSD/1P-LSD were more likely to endorse two items other people and their environment, and enhanced cognitive perfor-
on the scale, feeling overstimulated at the end of the day (p<.001) and mance. Some participants reported having experienced negative effects
difficulty concentrating (p = .047). Secondary analyses showed no while microdosing, including psychedelic effects typically associated
statistically significant associations between dose level and mean scale with regular doses, anxiety and physical symptoms, although few par-
scores. ticipants reported that these occurred regularly.
Two in five participants reported that their primary reason for mi-
crodosing was as an alternative mental health therapy, most of whom
Harm reduction and other practices
perceived that microdosing reduced depression and anxiety symptoms,
and improved their self-confidence and social connectedness. This
The most commonly reported harm reduction practices participants
supports the findings of other non-clinical studies that have described
usually used on microdosing days (i.e., more than 50% of the time) were
improved psychological wellbeing among people microdosing
not microdosing when feeling unwell (31.0%), avoiding alcohol (30.8%)
(Anderson et al., 2019; Fadiman & Korb, 2019; Johnstad, 2018; Politi &
and caffeine (23.8%), not microdosing in new or unfamiliar settings
Stevenson, 2019). However, most microdosing studies have excluded
(22.9%), and avoiding driving (20.3%; Table 4). One in four participants
people with previous or current mental health diagnoses and have not
reported regularly microdosing before important work or study events
reported microdosing motivations, a limitation that the present study
(25.7%), almost one in ten reported being more likely to use cannabis on
addresses.
microdose days (8.6%), and very few respondents reported using more
These findings suggest that standard mental health treatments like
alcohol on microdose days (0.9%). Participants microdosing with LSD/
antidepressants have not met the needs of many of our study partici-
1P-LSD were more likely than participants microdosing with psilocybin
pants, who were resorting to self-managed treatment with psychedelics.
to avoid caffeine on microdosing days (p = .005) and to use a reagent
As most participants had previous experience of using psychedelics, it is
test kit on newly obtained psychedelics (p<.001). Participants micro-
possible that they were less apprehensive about psychedelic use and
dosing with psilocybin were more likely to only microdose at home
had better knowledge of where to access them compared to those
(p = .001) or in quiet, familiar settings (p = .03).

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T. Lea, et al. International Journal of Drug Policy 75 (2020) 102600

Table 4
Harm reduction and other practices usually performed on microdosing days (i.e., more than 50% of the time).
All participants (n = 467) LSD/1P-LSD only (n = 187) Psilocybin only (n = 216) (%)
(%) (%)

Avoid microdosing when feeling physically unwell 31.0 28.3 29.6

Avoid or reduce alcohol on microdosing days 30.8 28.9 31.0
Avoid or reduce caffeine on microdosing days 23.8 29.4 17.6**
Avoid microdosing in situations new or outside regular routine 22.9 19.8 25.9
Avoid driving a car 20.3 20.3 19.0
Avoid stimulant drugs on microdosing days 19.3 18.7 16.7
Take lower dose on days doing something outside regular routine 18.8 17.6 20.4
Only take psilocybin mushrooms on an empty stomach 16.3 – 24.1
Avoid or reduce cannabis on microdosing days 15.4 15.0 14.8
Avoid microdosing if you have a hangover from alcohol 15.2 17.1 13.4
Only microdose at home 12.8 5.9 17.1**
Only microdose in quiet, familiar settings 12.8 9.1 16.2*
Avoid microdosing when feeling anxious 11.3 10.2 10.6
Test new batches you buy using a test kit (e.g., Ehrlich reagent test) 10.7 16.6 3.2***
Only microdose on non-work days 9.9 9.1 10.2
Avoid microdosing at work or college/university 9.2 8.0 9.3
Avoid taking SSRI antidepressants 9.0 7.0 9.3
Avoid microdosing when feeling depressed 6.9 5.9 5.1
Avoid taking lithium or tricyclic antidepressants 6.0 3.7 6.9
Check to see if mushrooms are not a poisonous variety by comparing to photos / 5.1 – 7.4
descriptions online or in a manual

None of the above 21.8 23.0 21.3

Number of practices reported (M, SD) 3.1 (3.0) 2.8 (2.6) 3.1 (3.0)

⁎
p<.05; ⁎⁎
p<.01; p<.001.
⁎⁎⁎

without prior experience. A recent study of psychedelic users found that These may be difficult conversations given the legal status of these
among those diagnosed with a mental health disorder, 62% had used substances, and individuals may be concerned about unsupportive or
psychedelics as an adjunct or replacement therapy to prescribed med- stigmatizing responses, degradation of the therapeutic relationship or
ication or psychotherapy (Mason & Kuypers, 2018). It is unsurprising fear of legal repercussions. Opting not to discuss changes in psychiatric
that some people are turning to alternative mental health treatments medications is common; a recent UK survey found that only half of
like microdosing. Psychiatric medications have variable levels of ef- those who stopped antidepressants did so in consultation with their
fectiveness and adherence (Moncrieff, 2018; Pampallona, Bollini, doctor (Read, Gee, Diggle & Butler, 2019).
Tibaldi, Kupelnick & Munizza, 2002), and treatment engagement for While popular media has often portrayed microdosing as a tool to
mental disorders is often below 50% (Whiteford et al., 2014). Recent improve focus, productivity and creativity (Glatter, 2015; Leonard,
meta-analyses have found that differences in the effectiveness of anti- 2015), less than one in five participants reported cognitive enhance-
depressants and placebo are small and unlikely to be clinical mean- ment as their primary motivation. We reported participants’ primary
ingful (Cipriani et al., 2018; Jakobsen et al., 2017). Antidepressant side motivation for microdosing, and it is possible that cognitive enhance-
effects are common (Read & Williams, 2018), and more than half report ment was a secondary motivation for some participants. Cognitive
withdrawal on cessation (56%), which can last from weeks to months benefits while microdosing were not as commonly reported as im-
(Davies & Read, 2019). proved mood, reduced anxiety and enhanced connectedness, but were
Participants microdosing with psilocybin were more likely than still reported by more than 40% of the sample. Enhanced cognitive
participants microdosing with LSD to report that their primary moti- performance was more likely to be reported by participants micro-
vation was as a treatment for depression and anxiety. It is unclear why dosing with LSD than psilocybin, which may reflect psychopharmaco-
this was found, but could be related to participants’ knowledge of re- logical differences, and LSD may be more suited to focus and attention
cent clinical trials, which are predominantly investigating psilocybin to a specific task than psilocybin (Nichols, 2016). Microdosing psy-
(Johnson & Griffiths, 2017) and have been reported in major news- chedelics for cognitive enhancement may carry fewer risks than using
papers. Additional research is required to better understand why people other nootropics like psychostimulants (Bisagno, Gonzalez & Urbano,
choose one psychedelic over another for different microdosing moti- 2016).
vations, as well as more focused research with people who have mi- Most participants reported having experienced unwanted effects
crodosed more than one substance. Few participants reported micro- while microdosing, although few reported that this was a common
dosing to manage substance use cessation or reduction, which could occurrence. It is concerning that one in five participants reported
reflect greater media attention on microdosing for cognitive enhance- having experienced paranoia while microdosing, and a more in-depth
ment and as alternative therapies for depression and anxiety, as well as investigation is warranted. Very few participants reported regularly
the higher prevalence of mood and anxiety disorders than substance use experiencing increased anxiety while microdosing, which does not
disorders in the general population (and acknowledging the high co- support suggestions that people with anxiety consider avoiding micro-
morbidity of substance use and mental disorders) (Lai, Cleary, dosing (Fadiman & Korb, 2019). Although we found no relationship
Sitharthan & Hunt, 2015; Whiteford et al., 2013). between dose and experiencing anxiety (which may be due to difficulty
Less than one in five participants had discussed microdosing with a in reliably assessing dose size), people microdosing to reduce anxiety
health professional. While this may be less of a concern for people may do better at lower doses. Adverse physical effects were not com-
microdosing for cognitive enhancement, people microdosing as a monly reported, consistent with evidence that there are few physical
treatment for mental health, and particularly those ceasing psychiatric harms from psychedelics (Nutt et al., 2010). Physical effects were more
medications to commence microdosing, should consider discussing commonly reported by participants microdosing LSD than psilocybin,
microdosing with their prescribing physician and psychotherapist. which could reflect psychopharmacological differences (Nichols, 2016).

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T. Lea, et al. International Journal of Drug Policy 75 (2020) 102600

Effects more commonly associated with regular psychedelic doses 2010). However, it is important to measure physical effects when ex-
such as euphoria and perceptual distortions were reported by most amining substance effects and this measure will be refined in future
participants at least once while microdosing. However, most of these survey rounds. Planned follow-up surveys will permit examination of
effects were uncommon. For the 22% of participants who reported longer-term perceived effects and outcomes, enduring unwanted effects
regularly experiencing euphoria while microdosing, this may indicate and maintenance and cessation of microdosing.
dosing too high, but may in fact be a desired effect. The accompanying The findings of this study contribute to the growing body of research
lift in mood and enthusiasm could feel like the microdose is “working”, that suggests a possible role for psychedelic microdosing as novel
particularly for people microdosing as a mental health therapy. therapies for people experiencing problems with mental health and
Participants motivated to microdose for mental health and cognitive substance use. Compared to psychedelic-assisted therapy with standard
enhancement were more likely to report improved psychological well- doses (typically 1–4 sessions with psychedelics, preceded and followed
being and enhanced performance, respectively. Some degree of by preparation and integration sessions) (Sessa, 2018), microdosing,
“meaning response” – a term proposed as an alternative con- either as a short-term or ongoing therapy, represents a different set of
ceptualisation of the “placebo effect” as an individual's response to the challenges for the design and implementation of clinical research and
meaning of their treatment – may be present, and clinical research on services. Attending a clinic for dosing several times a week, similar to
microdosing is needed (Moerman & Jonas, 2002). how opioid substitution treatment is often delivered, would be un-
Accurately microdosing with prohibited substances that have not realistic and a significant barrier to treatment for many people (Deering
been tested for purity is challenging, due to the very small doses re- et al., 2011; Madden, Lea, Bath & Winstock, 2008). Should clinical trials
quired and preparation and administration procedures that may result show microdosing to be effective therapies for mental and substance
in inconsistency between doses. Studies have found that LSD tabs often use disorders, the logistics of microdosing provision should be done
contain varying amounts of LSD, no LSD at all, and on rare occasions with consumer input in a way that is acceptable and responds to their
dangerous contaminants like NBOMe, a class of substances associated needs. While we await the findings of clinical research on microdosing,
with overdose and fatalities (Caldicott, Bright & Barratt, 2013; which could take several years, people who are dissatisfied with
Caudevilla et al., 2016; Gerace et al., 2019; van der Gouwe, Brunt, van available treatment services will continue to microdose as an alter-
Laar & van der Pol, 2017). The use of home testing kits to identify the native therapy. This may become more prevalent as media attention
presence of LSD should be encouraged as a harm reduction practice and community awareness of microdosing and psychedelic-assisted
when obtaining new batches, particularly as the use of test kits was therapy grows. Longitudinal social science research is thus a necessary
uncommon in our sample. For people who had unsuccessfully under- complement to clinical research, to gain insights into people's experi-
gone standard mental health and substance use therapies and are ex- ences of microdosing, develop better harm reduction resources, and
periencing positive outcomes from microdosing, microdosing with low consider how existing mental health and drug treatment services can
purity LSD or inert substances purchased as LSD could lead to the re- better support people who are microdosing at a time when these sub-
appearance of symptoms and relapse. Difficulties in accessing a ready stances are prohibited in most jurisdictions.
supply of psychedelics could lead some to reluctantly recommence
psychiatric medications. Should clinical trials show microdosing to be Declaration of Competing Interest
safe and effective, the establishment of a legal market would resolve
these issues. The authors have no conflicts of interest to declare.
This study has some limitations. Most participants were from high-
income countries, in paid employment and well educated. While bar- Acknowledgments
riers to mental health treatment are often related to perceived need and
stigma, people on low incomes often experience financial barriers to We would like to thank the participants who took the time to share
treatment and competing life demands that may limit opportunities to their experiences with us. We would like to thank Professor Norbert
access standard or alternative therapies (Andrade et al., 2014). The Scherbaum who provided feedback on an earlier version of the manu-
small number of participants from low- and middle-income countries script. This study was supported by an Alexander von Humboldt
may be related in part to the survey being offered only in English, lower Postdoctoral Research Fellowship held by the first author. The funding
availability of psychedelics and awareness of microdosing, as well as body had no role in study design, data collection, analysis and inter-
lower engagement with standard mental health services in these pretation, nor the preparation of this manuscript.
countries, which may preclude consideration of alternative therapies
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