AdolescentsDepressive DisordersAnxiety DisordersSubstance Use Disorders (SUD)LSDPsilocybin

Epidemiology of classic psychedelic substances: results from a Norwegian internet convenience sample

In a cross-sectional internet convenience sample of 770 self‑selecting Norwegian adults reporting a memorable classic psychedelic experience (predominantly psilocybin), most used psychedelics for recreational or therapeutic reasons and reported self‑perceived improvements in mental health and substance‑use symptoms, with many preparing, processing and integrating the experience though few received therapist support. Adverse reactions were generally mild and short‑lived but lasted one year or more in 4.2% of participants, including persistent flashbacks in 2.9%.

Authors

  • Morten Uthaug

Published

Frontiers in Psychiatry
individual Study

Abstract

Objective

In recent years, there has been a renewed interest in investigating the use of classic psychedelics such as psilocybin and lysergic acid diethylamide (LSD) in the treatment of mental disorders and substance use disorders. However, knowledge about the epidemiology of classic psychedelics in the Nordic countries is limited.

Methods

We recruited adult, Norwegian participants who have had a memorable experience after taking a classic psychedelic substance. They filled in an anonymous internet survey with 119 items covering matters related to recreational use of psychedelics using a secure, web-based application. Data are presented by using descriptive statistics (frequencies, means, and standard deviations).

Results

We recruited 841 participants, 770 (72% male; 88% 45 years or younger) of which were included in the data analysis. The intentions behind taking the psychedelic substance were mainly recreational (46.1%) or therapeutic (42.3%). Most participants reported that their most memorable experience was with psilocybin. As in modern era clinical trials, most participants were well-prepared before, did processing during, and did integration work after the experience, whereas only a minority were supported by a therapist. Self-perceived symptoms of various mental disorders and substance use disorders were prevalent in the sample. Most subjects reported improvements in their condition. Although adverse reactions were usually mild and short-lived, 4.2% lasted for 1 year or more. Persisting flashbacks were present for a year or more among 2.9% of the participants.

Conclusion

In this cross-sectional sample of Norwegian, self-selecting adults, we shed light on what characterizes the most memorable experience with a classic psychedelic substance, including short- and long-term risks and benefits. For the most part, the psychedelic experience led to improvements in self-perceived symptoms of mental disorders and substance use disorders. However, a small subset experienced persisting adverse reactions.

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Research Summary of 'Epidemiology of classic psychedelic substances: results from a Norwegian internet convenience sample'

Introduction

Classic psychedelic substances such as psilocybin and LSD have seen renewed research interest because recent clinical trials suggest therapeutic potential for conditions including anxiety, depression, and substance use disorders. These substances—also including mescaline and DMT—primarily act via the serotonin 5-HT2A receptor and, while physiologically low in toxicity, can provoke psychologically challenging acute reactions and, more rarely, longer-lasting conditions such as hallucinogen persisting perception disorder (HPPD). Large population studies outside the Nordic context have linked prior psychedelic use with lower rates of some mental-health problems, and internet surveys have been used to characterise both benefits and risks of recreational psychedelic use, but data from non‑English speaking countries remain limited. Kvam and colleagues set out to map the epidemiology of classic psychedelic substance use in Norway by surveying adults who reported a memorable psychedelic experience. The primary aims were to describe characteristics of that most memorable experience and its acute and persisting effects, and secondary aims included examining self‑reported changes in mental disorders and substance‑use disorders as well as the occurrence, duration and severity of persisting adverse reactions including proxy measures for HPPD.

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Study Details

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