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Improved colour blindness symptoms associated with recreational psychedelic use: Results from the Global Drug Survey 2017

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It is well documented that psychedelic drugs can have a profound effect on colour perception. After previous research involving psychedelic drug ingestion, several participants had written to the authors describing how symptoms of their colour blindness had improved. The Global Drugs Survey runs the world’s largest annual online drug survey. In the Global Drugs Survey 2017, participants reporting the use of lysergic acid diethylamide or psilocybin in the last 12 months were asked, We have received reports from some people with colour-blindness that this improves after they use psychedelics. If you have experienced such an effect can you please describe it in the box below, say what drug you took and how long the effect lasted. We received 47 responses that could be usefully categorised of which 23 described improved colour blindness. Commonly cited drugs were LSD and psilocybin; however, several other psychedelic compounds were also listed. Some respondents cited that the changes in colour blindness persisted, from a period of several days to years. Improved colour blindness may be a result of new photisms experienced in the psychedelic state aligning with pre-existing concepts of colour to be ascribed a label. Connections between visual and linguistic cortical areas may be enhanced due to disorder in the brain’s neural connections induced by psychedelics allowing these new photisms and concepts to become linked. This paper provides preliminary data regarding improved colour blindness accompanying recreational psychedelic use which may be further investigated in future iterations of the Global Drugs Survey or in a stand-alone Global Drugs Survey-managed psychedelics survey.
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Article
Improved colour blindness symptoms
associated with recreational psychedelic
use: Results from the Global Drug
Survey 2017
JEC Anthony
1
, A Winstock
2,3
, JA Ferris
4
and DJ Nutt
5
Abstract
It is well documented that psychedelic drugs can have a profound effect on colour perception. After previous research
involving psychedelic drug ingestion, several participants had written to the authors describing how symptoms of their
colour blindness had improved. The Global Drugs Survey runs the world’s largest annual online drug survey. In the
Global Drugs Survey 2017, participants reporting the use of lysergic acid diethylamide or psilocybin in the last 12 months
were asked,
We have received reports from some people with colour-blindness that this improves after they use psychedelics.
If you have experienced such an effect can you please describe it in the box below, say what drug you took and how
long the effect lasted.
We received 47 responses that could be usefully categorised of which 23 described improved colour blindness.
Commonly cited drugs were LSD and psilocybin; however, several other psychedelic compounds were also listed.
Some respondents cited that the changes in colour blindness persisted, from a period of several days to years.
Improved colour blindness may be a result of new photisms experienced in the psychedelic state aligning with pre-
existing concepts of colour to be ascribed a label. Connections between visual and linguistic cortical areas may be
enhanced due to disorder in the brain’s neural connections induced by psychedelics allowing these new photisms and
concepts to become linked. This paper provides preliminary data regarding improved colour blindness accompanying
recreational psychedelic use which may be further investigated in future iterations of the Global Drugs Survey or in a
stand-alone Global Drugs Survey-managed psychedelics survey.
Keywords
colour vision, LSD, psychedelics, psilocybin
Introduction
‘Mescaline raises all colours to a higher power and
makes the percipient aware of innumerable fine
shades of difference, to which, at ordinary times he is
completely blind’ (Huxley, 1954: 14).
I was completely astonished by the beauty of nature.
Our eyes see just a small fraction of the light in the
world. It is a trick to make a coloured [sic] world,
which does not exist outside of human beings. –
Albert Hofmann
These two quotes are a small fraction of the historical
literature describing how psychedelics greatly alter
one’s ordinary perception of colour. Such altered
perception has been previously assessed in a lab con-
trolled setting; finding changes in spectral patterns and
hue discrimination, which also varies between different
psychedelic drugs (Hartman and Hollister, 1963). This
1
University of Cambridge, UK
2
University College London, UK
3
Global Drug Survey, London UK
4
Centre for Health Services Research, The University of Queensland,
Australia
5
Imperial College London, UK
Corresponding author:
DJ Nutt, Imperial College London, London, UK.
Email: d.nutt@imperial.ac.uk
Drug Science, Policy and Law
Volume 6: 1–6
!The Author(s) 2020
Article reuse guidelines:
sagepub.com/journals-permissions
DOI: 10.1177/2050324520942345
journals.sagepub.com/home/dsp
challenges our current understanding of the role
of photoreceptors in central colour processing.
However, restrictions around research involving these
drugs made further studies into these phenomena more
challenging.
We had received reports from several people who
participated in our research that after taking a psyche-
delic, their previously colour-blind perception of the
world was changed. One participant said,
All my life I suffered from red-dichromacy/
protanopia ...after psilocybin I viewed Monet’s San
Giorgio Maggiore at Dusk, a painting which I had pre-
viously seen as a dull mass of brown and blue. All of
the colours I was previously unable to see were there on
the screen, and the emotion that I felt made me unable
to speak for about half an hour.
Similar comments were made on online forums such
as Reddit, ‘I’m colour blind, and I’m convinced
shrooms [sic] allows me to see all colours vibrantly’
(Anonymous, 2015). These reports suggested that
some individuals were experiencing improvements in
their colour blindness.
Normal colour vision is trichromatic arising from
comparisons between the differential excitement of
three types of colour-sensing cone in response to cer-
tain wavelengths of light. Colour blindness is an inher-
ited X-linked genetic disorder in which sufferers usually
have one less cone type in the retina. This results in a
reduced ability to compute spectral differences between
certain colours depending on the wavelength of light
the lost cone was most sensitive to. Psychedelics will
not alter the inherent colour sensing ability of the opti-
cal machinery in the retina; however, they may affect
central processing of the colour signal from the retina
thus affecting colour blindness.
Previous studies have found that psychedelics can
alter the way depressed patients respond to emotional
faces, particularly fearful ones (Roseman et al., 2018),
and a recent systematic review has highlighted that psy-
chedelic use has been associated with permanent
changes to personality in both the acute and long
term (Bouso et al., 2018). This demonstrates the estab-
lished potential of psychedelics to affect our central
processing of emotion and we were interested as to
whether psychedelics could assert similar effects by
improving colour vision in colour-blind people.
Colour-blind synaesthetes have reported experienc-
ing ‘alien’ photisms in relation to certain numbers
(Ramachandran and Hubbard, 2001) showing that
the brain can alter the colour experience beyond
input from the optic nerve. A recent case study has
reported a patient who has experienced synaesthesia
for over seven years since ingesting 75–150 milligrams
of 2C-B (Yanakieva et al., 2019), indicating that some
psychedelic experiences can produce long lasting
changes in perception. In both cases, the input to the
brain from the sense organs is unchanged; however, it
demonstrates the profound and persistent influence that
central processing can have on the sensory experience.
The Global Drugs Survey (GDS) runs the world’s
largest online drug survey and has been running annu-
ally since 2012. To address whether psychedelics
improved colour blindness in recreational psychedelic
users, a question was added to the Psychedelics section
at the end of GDS2017 asking colour-blind partici-
pants if they had noticed changes in their colour blind-
ness association with their use of psychedelics. The aim
was to gather preliminary data regarding this phenom-
enon with the intention of exploring this further in
future iterations of the GDS, if responses suggested
changes occurred at a significant prevalence.
Methods
Data were compiled from the GDS. GDS has been
running annually since 2012 (naming convention
refers to year the data are released, not the year of
collection) and runs the world’s largest annual online
drug survey. The survey uses an anonymous cross-
sectional design. The GDS2017 ran for seven weeks
between the second week of November and end of
December 2016 involving 119,075 participants after
sample cleaning. Direct participant recruitment
occurred through media partnerships in over 20 coun-
tries including outlets such as Vice, The Guardian and
Zeit-on-Line, with secondary recruitment occurring via
sharing of the content on social media such as
Facebook or discussion forums such as Reddit
(Barratt et al., 2017). Multi-institutional ethics approv-
al was obtained from the Kings College London
Research Ethics Committee 11671/001: Global Drug
Survey, University of Queensland (No. 2017001452)
and The University of New South Wales (HREC
HC17769) Research Ethics Committees.
As part of GDS2017 a series of questions were
included at the end of the Psychedelics section, to
probe the effects of recreational use of psychedelics
on colour blindness. Participants reporting the use of
LSD or psilocybin in the last 12 months were asked,
We have received reports from some people with
colour-blindness that this improves after they use psy-
chedelics. If you have experienced such an effect can
you please describe it in the box below, say what drug
you took and how long the effect lasted.
The information obtained was received in the form of
‘open-ended’ qualitative anecdotes. The survey was
2Drug Science, Policy and Law
translated into 14 main languages including German,
Italian, French, Danish, Portuguese, Spanish,
Hungarian, Flemish and Polish.
Responses were categorised as follows:
1. Colour blind and colour change (EXPERIENCED)
2. Colour blind and no colour change (NOT
EXPERIENCED)
For a response to be marked ‘experienced’, the
respondent had to imply a marked difference in ability
to distinguish between colours; however, this effect
didn’t have to extend beyond the period of intoxica-
tion. Since the question was asked, ‘If you have
experienced such an effect’, implying both colour
blindness and improvement, respondents weren’t
required to positively identify as colour blind. Several
respondents reported experiences of increased colour
intensity; however, these were marked negative as this
did not prove an increased ability to discern between
colours.
An ideal ‘experienced’ response (ID 19670) was,
‘LSD, I’m red/green colour blind and the effect lasted
the following 3 or 4 days’.
An ideal ‘not experienced’ response (ID 13385) was,
‘I have deuteranopia, but unfortunately I didn’t sense
any change in my colour perception on psilocybin.
(I also figured this out using example images for
people with colour blindness)’.
Graphs were constructed using RStudio (RStudio
Team, 2019).
Results
The question received 382 responses from 10 different
countries of which 47 responses could be categorised
with regards to the question. Of the categorised
responses, 23 experienced and 24 didn’t experience
improved colour blindness symptoms (Figure 1).
Despite the low number of categorised responses,
there was a sufficient number of respondents reporting
improved colour blindness to suggest that, in some
people, recreational psychedelic use may improve
colour blindness.
We were interested in whether the specific psyche-
delic drug used would influence the prevalence of
improved colour blindness being experienced. Of the
23 respondents who experienced the effect, 15 indicated
the drug used, with some indicating multiple drugs.
LSD and psilocybin mushrooms were the most com-
monly cited psychedelic drugs (Figure 2). There were
single mentions of novel psychedelic substances used
with which this effect occurred. This included substitut-
ed 2C family drugs such as 25I-NBOMe and 2C-C
and several novel substituted tryptamines such as
5-MeO-DMT and 4-HO-MET. Responses did not indi-
cate that a specific drug induced changes in colour
blindness with a greater frequency than other drugs.
The question also asked about the length of time the
changes in colour blindness lasted for. Of respondents
who experienced changes in their colour blindness,
39% indicated that their changed perception continued
for a period after the drug had worn off ranging from
three days to ‘years’. The time frames given for
Figure 1. Graph showing the number of respondents reporting
about changes to their colour blindness following recreational
psychedelic use. Experienced means respondents reported
improved colour blindness, not experienced means respondents
did not report improved colour blindness.
Figure 2. Graph showing the number of times certain drugs
were cited to improve colour blindness symptoms. The ‘other’
category includes substituted 2C family drugs and novel
substituted tryptamines. Some respondents listed multiple drugs.
LSD: lysergic acid diethylamide.
Anthony et al. 3
persistence of this phenomenon beyond the immediate
effects of the drug were largely non-specific and further
quantification was not possible due to the nature of the
responses given.
Discussion
This study explored the effects of recreational psyche-
delic use on colour blindness through a self-reported
survey question included in GDS2017. There were 382
responses to the question of which 47 could be categor-
ised. Of these, 23/47 reported experiencing improved
colour blindness relating to recreational psychedelic
use, defined as an improved ability to discriminate
between colours. Respondents reported a range of
drugs and time frames associated with improved
colour vision. The number of respondents reporting
improved colour blindness suggests that such improve-
ments do occur in a proportion of recreational users of
psychedelics. Psychedelics may facilitate the experience
of an expanded spectrum of colours. In the excited psy-
chedelic state, new communication between cortical
regions may link new photisms to pre-existing concepts
of colours, thus facilitating a new colour experience
and improving colour blindness. The self-reported
anonymous nature of the GDS made it hard to verify
claims and the 20–30 minutes length of the survey
meant responses to this question, placed at the end,
may have been affected by participant fatigue, thus
reducing their quality and utility. In the future, we
plan to run a more in depth GDS managed psyche-
delics survey to further gather reports regarding this
phenomenon.
Psychedelics do not alter the innate nature of the
visual signal from the retina because the defect is of
genetic origin – the result of fewer ‘colour-sensing’
cones in the retina. The signal sent to the primary
visual cortex from the retina likely remains unchanged
under the influence of psychedelics. Colour signals are
then processed, via the ventral visual pathway, in the
V4 region of the occipital cortex and it is from this
point that psychedelics may affect higher order
processing and ultimately perception of colour.
Psychedelics may result in new colours being experi-
enced, termed ‘alien’ photisms. In the psychedelic
state, increased neural plasticity may aid the formation
of associations between new photisms and pre-existing
concepts of colours that were not previously distin-
guished, thus improving the range of colours experi-
enced and improving colour blindness.
Classical psychedelics, such as LSD and psilocybin,
are 5-HT
2A
receptor agonists (Glennon et al., 1984);
however, each psychedelic drug has its own unique
binding profile, particularly regarding other 5-HT
receptor subtypes (Ray, 2010). These differences may
affect the extent to which different psychedelic drugs
can improve colour blindness; however, the nature of
the responses provided did not allow such analysis.
Despite the variation in binding profiles, most psyche-
delic drugs principally agonise the 5-HT
2A
receptor.
Agonism at this receptor depolarises deep-layer pyra-
midal neurons in the prefrontal cortex (Andrade, 2011)
resulting in disordered signalling and a window
of increased neural plasticity, described by
Carhart-Harris et al. (2014) as the ‘Entropic Brain
Hypothesis’. The period of increased uninhibited corti-
cal signalling induced by modulation of the 5-HT
2A
receptor may enable new neural connections to form.
Psilocybin, a classical psychedelic, has been shown to
increase the formation of homological scaffolds of
brain functional networks under fMRI analysis (Petri
et al., 2014) and such changes in brain chemistry may
persist beyond the immediate pharmacological actions
of the drug (Carhart-Harris and Nutt, 2017). We pro-
pose that the new neural networks may enable new
associations between the perceived and linguistically
known colour of objects, altering the experience of
colour perception.
Under the influence of psychedelic drugs, users may
experience an expanded array of colours, possibly as a
result of enhanced entropy in the V4 cortex leading to
over-exaggerated cross visual field comparisons. This
does not necessarily mean the colours seen of objects
are more representative of their true colour, merely a
wider variety of colours are experienced (Hartman and
Hollister, 1963). Some of the colours experienced in
this state may be entirely new to the user. Colour
blind synaesthetes have reported experiencing ‘alien’
photisms, which are reported to not exist within the
range of their normal perception, in relation to certain
numbers (Ramachandran and Hubbard, 2001), show-
ing the ability of the brain to alter the experience of
colour beyond optic nerve input. Thus, the notion of a
new colour being experienced under the influence of
psychedelic drugs is not unfathomable.
The ‘alien’ colours experienced whilst under the
influence of psychedelic drugs may become ascribed
to objects based upon known linguistic ideas of any
object, for example an apple is red or the sky is blue.
Despite having difficulty distinguishing these colours,
depending on the type of colour blindness, individuals
still have a concept of these colours. Congenitally blind
children have been shown to have a 69–80% agreement
in associations of colours relative to their sighted coun-
terparts. For example, yellow may be conceptualised as
a‘happy, nice, shiny colour’. It was shown that these
concepts of colour were purely language based and
relied on being taught their associations (Anthony,
1996). Alien colours experienced in the psychedelic
state may align with the colour-blind user’s conceptual
4Drug Science, Policy and Law
understanding of a colour they are not normally able to
observe. This may be ascribed to certain objects leading
to lexically driven changes in the perception of specific
objects in line with their colour. Such changes would be
unlikely to occur universally or consistently due to dif-
ferent colour associations between individuals coupled
to different sets and settings.
Synaesthesia may be traditionally be thought of as
‘seeing sound’ or mixing of traditional special senses;
however, there are a plethora of other inducer-
concurrent associations (Luke and Terhune, 2013).
There are a variety of explanations for the phenome-
non of synaesthesia including increased neural connec-
tivity in the psychedelic state (Petri et al., 2014)
or cortical disinhibition and hyperexcitability
(Yanakieva et al., 2019). It is feasible that increased
connection between regions of the cortex responsible
for higher colour perception, V4, to concepts of
colour in language centres may occur in the psychedelic
state through ‘noisy’ disordered signalling. New con-
nections between these aforementioned areas of associ-
ation cortex complement Whorfian ideas of colour
discrimination which may affect an individual’s percep-
tions of coloured objects, consequently leading to
the improvement of colour discrimination in the
colour blind.
There is a growing body of evidence to suggest sero-
tonergic hallucinogens can affect recognition of facial
expressions (Rocha et al., 2019). LSD has been shown
to reduce recognition of sad or fearful faces alongside
enhancing emotional empathy (Dolder et al., 2016). In
a different study, the day after a 25-milligram psilocy-
bin treatment, enhanced amygdala responses to emo-
tional faces, particularly fearful ones, were found,
suggesting alterations in the manner in which depressed
patients respond to emotional stimuli (Roseman et al.,
2018). The brain contains concepts of emotions and if
the response to emotional stimuli and their associations
in the brain can be altered it is plausible that our asso-
ciations of colours and thus their perception can be
changed too, particularly because the raw visual signals
entering the brain in the cases of recognising facial
expression and processing colour are constant.
Long term changes in colour blindness, lasting
beyond psychedelic experience, were reported by 39%
of respondents. This would suggest that such effects are
likely to be common in a larger proportion of the
colour-blind population. However, the number of
colour-blind respondents not experiencing this was
likely underreported due to the positive nature of the
question and thus this high proportion is likely an
artefact of the wording. A possible reason for the per-
sistence of changes in colour vision could be the extra-
pharmacological effects of psychedelics such as set and
setting, which likely vary between respondents,
producing lasting changes in neural networks
(Carhart-Harris and Nutt, 2017). Dosage may also
account for this as levels of 5-HT
2A
receptor occupancy
have been shown to correlate with the intensity of
effects experienced (Madsen et al., 2019) which may
complement the extra-pharmacological effects.
However, the design of the GDS study makes it diffi-
cult to control for these factors. There are recorded
instances of psychedelic-induced visual perceptual
changes persisting. Hallucinogen persisting perception
disorder is estimated to have an occurrence of 1/50,000
in regular users of psychedelic drugs (Halpern et al.,
2016) and some case studies have reported symptoms
lasting for months or years (Martinotti et al., 2018).
Recently, a case of acquired synaesthesia was reported
in a 29-year-old male following the use of 2C-B
which had persisted for over seven years (Yanakieva
et al., 2019).
This study found that a proportion of colour-blind
participants reported improved colour blindness fol-
lowing the recreational use of psychedelics, defined as
an improved ability to discern between colours. There
are several limitations to the study. The data consisted
of self-reported anecdotes of variable quality, some of
which proved hard to interpret, thus making accurate
quantification and standardised interpretation difficult.
The reports were self-validated both as to the nature of
the colour blindness and whether this phenomenon was
experienced. Colour blindness is not a unimodal disor-
der and different forms of colour blindness may have
been affected differently. We were unable to obtain this
level of detail with the responses given. The question
was asked in a ‘special section’ at the end of GDS2017
which itself takes 20–30 minutes to complete and
number of usable responses was small, 47/382. Some
responses didn’t relate to the question or were too dif-
ficult to decipher, which may reflect participant fatigue.
Language barriers were unlikely to play a role due to
the wide variety of language translations available.
In future iterations of the GDS, we plan to revisit
this exploratory study and more clearly identify the
nature of pre-existing colour vision deficit and more
specifically assess changes in visual perception, the
drug taken and better quantification of the persistence
of the effects. Rather than a free-text response, partic-
ipants could provide answers in a multiple-choice
format with the question deconstructed into discrete
parts. Due to the length of the standard GDS, a
GDS managed stand-alone psychedelics survey may
be more suitable to minimise participant fatigue. This
would enable a variety of phenomena regarding recre-
ational use of psychedelics to be evaluated, not just
colour perception, such as visual acuity which was
mentioned by several respondents.
Anthony et al. 5
Acknowledgments
The authors would like to thank the participants of the
GDS2017 for giving their time to complete the survey and
making this study possible. They are grateful to Sophia West
for her help in translating the responses into English.
Declaration of conflicting interests
The author(s) declared the following potential conflicts of
interest with respect to the research, authorship, and/or pub-
lication of this article: A Winstock is the owner and founder
of Global Drug Survey (GDS). Global Drug Survey Ltd is an
independent self-funded organisation.
Funding
The author(s) received no financial support for the research,
authorship, and/or publication of this article.
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6Drug Science, Policy and Law
... Intriguingly, findings from a 2020 study using data from the Global Drug Survey, the largest annual international online survey on drug use (Global Drug Survey, 2023), suggest that psychedelics might durably improve CVD symptoms in some people (Anthony et al., 2020). In that study, 49% (23/47) of respondents with CVD and psychedelic use reported psychedelic-associated symptom amelioration, most commonly after lysergic acid diethylamide (LSD) or psilocybin use. ...
... This case report builds upon findings from the Global Drug Survey in which participants reported amelioration in CVD symptoms following psychedelic use, possibly lasting for years in some cases (Anthony et al., 2020). Our subject, a 35-year-old man with mild deuteranomalia, experienced a quantifiable partial improvement in his CVD lasting for at least sixteen days, which led to reclassification of mild color-blindness to normal color vision according to self- Figure 1. ...
... The mechanism for the reported benefits of CVD by psilocybin remains unclear. Anthony & colleagues have hypothesized that since the brain can alter experience of color beyond optic nerve input (Ramachandran and Hubbard, 2001), alterations in higher-level visual processing induced by psychedelics likely underly their ability to improve CVD in some individuals (Anthony et al., 2020). Since CVD typically results from a genetic defect and psychedelics likely do not alter the actual visual signal coming from the retina, they may produce an expanded spectrum of color perception in people with CVD by inducing new neural connections between cortical regions that "link new photisms to pre-existing concepts of colors, thus facilitating a new color experience" (Anthony et al., 2020). ...
Article
Background Recent survey data indicate that some people report long-term improvement in color vision deficiency (CVD), also known as color blindness, following use of psychedelics such as lysergic acid diethylamide (LSD) and psilocybin. However, there are no objective data reported in the medical literature quantifying the degree or duration of CVD improvement associated with psychedelic use. Case presentation Here we present the case of a subject with red-green CVD (mild deuteranomalia) who self-administered the Ishihara Test to quantify the degree and duration of CVD improvement following the use of 5 g of dried psilocybin mushrooms. Self-reported Ishihara Test data from the subject revealed partial improvement in CVD peaking at 8 days and persisting for at least 16 days post-psilocybin administration. This improvement may have lasted longer, though the subsequent observations are confounded by additional substance use. Conclusion A single use of psilocybin may produce partial improvements in CVD extending beyond the period of acute effect, despite this condition typically resulting from a genetic defect. Systematic exploration of this possible phenomenon is needed to confirm our findings, gauge their generalizability, and determine the mechanism of action.
... The UPSIT tests for odor identification but does not test olfactory threshold so we are unable to comment on the olfactory threshold in these three cases. These cases present an interesting parallel with previously described cases of individuals with colorblindness who endorsed improvement in color discrimination following the use of psychedelic substances (Anthony et al. 2020). Color blindness is an X-linked genetic disorder resulting in one less cone type in the retina which reduces an individual's ability to distinguish between certain colors. ...
Article
Cultural awareness of anosmia and microsmia has recently increased due to their association with COVID-19, though treatment for these conditions is limited. A growing body of online media claims that individuals have noticed improvement in anosmia and microsmia following classic psyche-delic use. We report what we believe to be the first three cases recorded in the academic literature of improvement in olfactory impairment after psychedelic use. In the first case, a man who developed microsmia after a respiratory infection experienced improvement in smell after the use of 6 g of psilocybin containing mushrooms. In the second case, a woman with anosmia since childhood reported olfactory improvement after ingestion of 100 µg of lysergic acid diethylamide (LSD). In the third case, a woman with COVID-19-related anosmia reported olfactory improvement after microdosing 0.1 g of psilocybin mushrooms three times. Following a discussion of these cases, we explore potential mechanisms for psychedelic-facilitated improvement in olfactory impairment, including serotonergic effects, increased neuroplasticity, and anti-inflammatory effects. Given the need for novel treatments for olfactory dysfunction, increasing reports describing improvement in these conditions following psychedelic use and potential biological plausibility, we believe that the possible therapeutic benefits of psychedelics for these conditions deserve further investigation. ARTICLE HISTORY
... These results largely reflect previous research showing such phenomena are not uncommon, but are rarely cited as disabling or severely distressing and therefore rarely meet the criteria for hallucinogen persisting perception disorder (HPPD) recognised in DSM-5 (Carhart-Harris and Nutt, 2010;Muller et al., 2022). Such experiences may represent an enduring effect of psychedelics on visual processing, or may represent an increased awareness of the normal breadth of visual experience (Anthony et al., 2020). ...
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Background: Growing numbers of people are using psychedelics for personal psychotherapy outside clinical settings, but research on such use is scarce. Aims: This study investigated the patterns of use, self-reported outcomes and outcome predictors of psychedelic 'self-treatment' of mental health conditions or specific worries/concerns in life. Methods: We use data from the Global Drug Survey 2020, a large online survey on drug use collected between November 2019 and February 2020. In all, 3364 respondents reported their self-treatment experiences with lysergic acid diethylamide (N = 1996) or psilocybin mushrooms (N = 1368). The primary outcome of interest was the 17-item self-treatment outcome scale, items reflecting aspects of well-being, psychiatric symptoms, social-emotional skills, and health behaviours. Results: Positive changes were observed across all 17 outcome items, with the strongest benefits on items related to insight and mood. Negative effects were reported by 22.5% of respondents. High intensity of psychedelic experience, seeking advice before treatment, treating with psilocybin mushrooms and treating post-traumatic stress disorder were associated with higher scores on the self-treatment outcome scale after averaging values across all 17 items. Younger age, high intensity of experience and treating with LSD were associated with increased number of negative outcomes. Conclusions: This study brings important insights into self-treatment practices with psychedelics in a large international sample. Outcomes were generally favourable, but negative effects appeared more frequent than in clinical settings. Our findings can help inform safe practices of psychedelic use in the community, and inspire clinical research. Future research can be improved with utilisation of prospective designs and additional predictive variables.
... The majority (52%) of those using psychedelics reported doing so to improve their wellbeing, with others reporting use to deal with emotional concerns (32%) or to address a psychiatric condition (15%). Other evidence suggests psychedelics are used recreationally to treat anything from eating disorders (4), to racial trauma (5), chronic pain (6) and colour blindness (7); suggesting that recreational users are attempting to bene t from the therapeutic effects of psychedelics observed in clinical studies in recreational settings. ...
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Background Alongside a recent revival in the use of psychedelics in clinical settings, there have been increases in the prevalence of recreational use, with many using psychedelics to deal with difficult emotions or to improve wellbeing. While clinical research is conducted in carefully controlled settings, this is not necessarily the case for recreational use. In this mixed-methods study, we aimed to develop an understanding of frequently used psychedelic harm reduction practices in recreational settings and how their use relates to the psychedelic experience. We also aimed to characterise users’ first and most recent psychedelic trips to understand how harm reduction changes with experience. Methods Participants (n = 163) recounted their first and most recent psychedelic experience by providing details about the harm reduction practices they employed and completing the Challenging Experience Questionnaire (CEQ) and Emotional Breakthrough Inventory (EBI). We also asked open ended questions for a more in-depth qualitative understanding of their views on psychedelic harm reduction. Results Using ANOVA, we observe greater use of harm reduction practices for participants’ most recent versus first psychedelic experience and that use of these practices is positively associated with EBI scores and negatively associated with CEQ scores (particularly for the first experience). Participants engaged in a wide range of harm reduction practices and we provide details of those which are most commonly used and those which are deemed most important by experienced users. Our qualitative analysis indicated that participants were largely positive about psychedelics and many recounted profound positive experiences. While specifics of the drug they were taking was important for aspects of harm reduction, participants largely focused on the importance of ensuring a good ‘set and setting’ for enhancing positive effects. Conclusions Our research helps us understand how engagement in harm reduction may increase with experience. Our mixed methods data sheds light on the perceived importance of different harm reduction practices and examines their association with the psychedelic experience itself. Together, our research has important implications for the development of psychedelic harm reduction advice and provides opportunities for future research to explore the importance of these different practices in more detail.
... The majority (52%) of those using psychedelics reported doing so to improve their well-being, with others reporting use to deal with emotional concerns (32%) or to address a psychiatric condition (15%). Other evidence suggests psychedelics are used recreationally to attempt to self-treat anything from eating disorders [5], to racial trauma [6], chronic pain [7] and colour blindness [8]. This suggests that recreational users are attempting to benefit from the therapeutic effects of psychedelics observed in clinical studies in recreational settings and applying them to a wide range of untested issues. ...
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Background Alongside a recent revival in the use of psychedelics in clinical settings, there have been increases in the prevalence of recreational use, with many using psychedelics to deal with difficult emotions or to improve well-being. While clinical research is conducted in carefully controlled settings, this is not necessarily the case for recreational use. In this mixed methods online survey study, we aimed to develop an understanding of frequently used psychedelic harm reduction practices in recreational settings and how their use relates to the psychedelic experience. We also aimed to characterise users’ first and most recent psychedelic trips to understand how harm reduction changes with experience. Methods Participants ( n = 163) recounted their first and most recent psychedelic experience by providing details about the harm reduction practices they employed and completing the Challenging Experience Questionnaire (CEQ) and Emotional Breakthrough Inventory (EBI). We also asked open-ended questions for a more in-depth qualitative understanding of their views on psychedelic harm reduction. Results Using ANOVA, we observe greater use of harm reduction practices for participants’ most recent versus first psychedelic experience and that use of these practices is positively associated with EBI scores and negatively associated with CEQ scores (particularly for the first experience). Participants engaged in a wide range of harm reduction practices and we provide details of those which are most commonly used and those which are deemed most important by experienced users. Our qualitative analysis indicated that participants were largely positive about psychedelics and many recounted profound positive experiences. While specifics of the drug they were taking was important for aspects of harm reduction, participants largely focused on the importance of ensuring a good “set and setting” for enhancing positive effects. Conclusions Our research helps us understand how engagement in harm reduction may increase with experience. Our mixed methods data shed light on the perceived importance of different harm reduction practices and examine their association with the psychedelic experience itself. Together, our research has important implications for the development of psychedelic harm reduction advice and provides opportunities for future research to explore the importance of these different practices in more detail.
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The field of psychedelic research is undergoing a revival, yet research focused on non-clinical psychedelic use remains relatively limited. The current qualitative study sheds light on how people use magic mushrooms, what they perceive the effects of such use to be, and the meanings that users attach to their magic mushroom experiences. To be eligible to participate in the study, participants were required to be young adults who had used magic mushrooms within the past three months and residents of Victoria, Canada. Semi-structured, one-on-one in-person interviews regarding magic mushroom use habits, culture, knowledge and other factors were conducted with each participant and subsequently analyzed thematically. Participants associated magic mushroom use with lasting impacts on their lives including transformation and learning experiences. Additionally, participants described strategies to optimize their magic mushroom experiences, including engaging in research regarding magic mushrooms as well as making use of peer supports. Furthermore, aspects of magic mushroom experiences conceptualized as harmful in previous studies were described by participants as associated with learning experiences and few harms. Participants' perceived positive outcomes and relatively low risk profile warrants further research to inform how magic mushroom users can maximize potential positive outcomes and also minimize harms.
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Background Recognition of emotions in facial expressions (REFE) is a key aspect of social cognition. Anxiety and mood disorders are associated with deficits in REFE, and anxiolytics and antidepressants reverse these deficits. Recent studies have shown that serotonergic hallucinogens (i.e. ayahuasca, dimethyltryptamine, psilocybin, lysergic acid diethylamide [LSD], and mescaline) have anxiolytic and antidepressant properties, but their effects on REFE are not well understood. The purpose of the study was to conduct a systematic review analyzing the effects of serotonergic hallucinogens on REFE in humans. Methods Studies published in the PubMed, PsycINFO, and Web of Science databases until 19 October 2018 which analyzed the effects of serotonergic hallucinogens on REFE in humans were included. Results Of the 62 studies identified, 8 studies were included. Included studies involved the administration of a single or a few doses of LSD or psilocybin, and most trials were randomized and controlled with placebo. LSD and psilocybin reduced the recognition of negative emotions in most studies and modulated amygdala activity to these stimuli, which was correlated with antidepressive effects in patients. Both drugs were well tolerated. Conclusions Serotonergic hallucinogens reduced the recognition of negative emotions by modulating amygdala activity. Despite the small sample sizes, results suggest that serotonergic hallucinogens show promising beneficial effects on deficits in REFE.
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Hallucinogen Persisting Perception Disorder (HPPD) is a rare, and therefore, poorly understood condition linked to hallucinogenic drugs consumption. The prevalence of this disorder is low; the condition is more often diagnosed in individuals with a history of previous psychological issues or substance misuse, but it can arise in anyone, even after a single exposure to triggering drugs. The aims of the present study are to review all the original studies about HPPD in order to evaluate the following: (1) the possible suggested etiologies; (2) the possible hallucinogens involved in HPPD induction; (3) the clinical features of both HPPD I and II; (4) the possible psychiatric comorbidities; and (5) the available and potential therapeutic strategies. We searched PubMed to identify original studies about psychedelics and Hallucinogen Persisting Perception Disorder (HPPD). Our research yielded a total of 45 papers, which have been analyzed and tabled to provide readers with the most updated and comprehensive literature review about the clinical features and treatment options for HPPD.
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A decline in response rates in traditional household surveys, combined with increased internet coverage and decreased research budgets, has resulted in increased attractiveness of web survey research designs based on purposive and voluntary opt-in sampling strategies. In the study of hidden or stigmatised behaviours, such as cannabis use, web survey methods are increasingly common. However, opt-in web surveys are often heavily criticised due to their lack of sampling frame and unknown representativeness. In this article, we outline the current state of the debate about the relevance of pursuing representativeness, the state of probability sampling methods, and the utility of non-probability, web survey methods especially for accessing hidden or minority populations. Our article has two aims: (1) to present a comprehensive description of the methodology we use at Global Drug Survey (GDS), an annual cross-sectional web survey and (2) to compare the age and sex distributions of cannabis users who voluntarily completed (a) a household survey or (b) a large web-based purposive survey (GDS), across three countries: Australia, the United States, and Switzerland. We find that within each set of country comparisons, the demographic distributions among recent cannabis users are broadly similar, demonstrating that the age and sex distributions of those who volunteer to be surveyed are not vastly different between these non-probability and probability methods. We conclude that opt-in web surveys of hard-to-reach populations are an efficient way of gaining in-depth understanding of stigmatised behaviours and are appropriate, as long as they are not used to estimate drug use prevalence of the general population.
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Chapter
Hallucinogen persisting perception disorder (HPPD) is rarely encountered in clinical settings. It is described as a re-experiencing of some perceptual distortions induced while intoxicated and suggested to subsequently cause functional impairment or anxiety. Two forms exist: Type 1, which are brief “flashbacks,” and Type 2 claimed to be chronic, waxing, and waning over months to years. A review of HPPD is presented. In addition, data from a comprehensive survey of 20 subjects reporting Type-2 HPPD-like symptoms are presented and evaluated. Dissociative Symptoms are consistently associated with HPPD. Results of the survey suggest that HPPD is in most cases due to a subtle over-activation of predominantly neural visual pathways that worsens anxiety after ingestion of arousal-altering drugs, including non-hallucinogenic substances. Individual or family histories of anxiety and pre-drug use complaints of tinnitus, eye floaters, and concentration problems may predict vulnerability for HPPD. Future research should take a broader outlook as many perceptual symptoms reported were not first experienced while intoxicated and are partially associated with pre-existing psychiatric comorbidity.