User perceptions of the benefits and harms of hallucinogenic drug use: A web-based questionnaire study

Despite widespread recreational and ceremonial use of hallucinogenic drugs, systematic data on users' own perceptions of the benefits and harms associated with use were sparse at the time of this study. Early controlled clinical research had demonstrated therapeutic potential for LSD and psilocybin in supportive settings, but the subjective experience of recreational users — who constitute the large majority of hallucinogen-using individuals — had not been formally characterised through structured questionnaire methodology. This study employed a web-based questionnaire to investigate recreational and occasional users' perceptions of the acute and prolonged effects, benefits, and harms of six drugs: LSD, psilocybin, MDMA, ketamine, cannabis, and alcohol, with particular focus on perceived therapeutic potential and long-term effects on wellbeing.

A web-based questionnaire was distributed primarily through drug-information websites, targeting recreational and occasional drug users. Over 600 questionnaire submissions were received. Participants were asked about perceived acute and long-term effects of each drug they had used, which drugs they considered most beneficial and most harmful, and whether specific drugs had helped with health conditions including mood disorders, addiction, and migraine. Structured rating items assessed perceived seriousness of negative effects, perceived therapeutic potential on a ten-point scale, and liking of short-term effects. Participants could also provide free-text comments. A subset completed a more comprehensive version of the questionnaire including additional items on long-term perceptual changes.

LSD and psilocybin were rated substantially lower on perceived seriousness of negative effects (LSD: 2.4±0.1; psilocybin: 3.9±0.1) compared to ketamine (4.8±0.2), cannabis (4.4±0.1), and alcohol (7.5±0.1). LSD achieved the highest perceived therapeutic potential rating (6.9±0.1), followed closely by MDMA (6.6±0.1) and psilocybin (6.5±0.1), whilst alcohol received a near-zero therapeutic potential rating (0.6±0.1). Long-term wellbeing effects were most positive for LSD — 67% of LSD users reported a positive or very positive long-term effect on wellbeing — with psilocybin second at 60%. Free-text comments from LSD and psilocybin users documented a range of reported health benefits including alleviation of depressive symptoms (23 and 24 subjects respectively), anxiety reduction, addiction assistance, and migraine relief. More general benefits included improved insight, perspective, optimism, self-acceptance, and sense of inner-peace. Alcohol was rated as having the most negative long-term wellbeing impact, with only 6% of users reporting any positive effect.

The results indicate that, in the self-report of recreational users, the classic hallucinogens LSD and psilocybin are perceived as substantially more beneficial and less harmful than alcohol, cannabis, or ketamine — a pattern broadly consistent with the controlled clinical literature suggesting therapeutic potential for these compounds. The convergence between self-report perceptions and clinical findings lends some ecological validity to both bodies of evidence, though it must be interpreted cautiously given significant sampling limitations. The primary methodological limitation acknowledged by the authors is that the questionnaire was disseminated predominantly through websites with a favourable attitude towards drug use, making it highly likely that individuals with positive experiences were disproportionately represented. Attempts to recruit through websites with more negative perspectives on drug use were unsuccessful. Results should therefore be considered as characterising the perceptions of a self-selected, drug-positive population rather than as a representative cross-sectional sample of hallucinogen users.

A web-based questionnaire survey of recreational drug users found that LSD and psilocybin were perceived as having substantially lower harm and higher therapeutic potential than alcohol, ketamine, or cannabis, with the majority of LSD and psilocybin users reporting positive long-term effects on wellbeing. Reported health benefits included mood disorder alleviation, addiction assistance, and migraine relief, alongside broader improvements in insight, perspective, and self-acceptance. Significant sampling bias toward drug-positive individuals limits generalisability, though the findings are broadly consistent with the controlled clinical research literature on the therapeutic potential of classic hallucinogens.