British Journal of Addiction
August 1, 1992
Nadia Solowij, Wayne Hall, Nicole Lee
417 citations
Ecstasy (MDMA) is a recreational drug gaining worldwide popularity, yet research on its use and effects is limited. A survey of 100 users recruited through peer networks found that Ecstasy is primarily used infrequently for fun at dance parties and social gatherings. The main effects reported were positive mood, intimacy, and closeness, along with stimulant and psychedelic properties. Side effects and residual effects were no more severe than those of amphetamines or hallucinogens. Tolerance to positive effects developed with frequent use, while negative effects increased. Animal research indicates neurotoxicity to serotonergic nerve terminals, warranting caution until human hazard levels are determined.
Annual Review of Psychology
August 2, 2024
Keith Humphreys, Daniel Stjepanović, Wayne Hall et al.
18 citations
Many psychedelic drugs lack rigorous evaluation, but the science is improving. Ketamine shows promise for treatment-resistant depression despite risks like addiction and cystitis. MDMA for PTSD and psilocybin for depression, end-of-life dysphoria, and alcohol use disorder merit further replication. The mechanisms of benefit and harm remain unclear. Rigorous research is needed to assess therapeutic potential, and policies should prioritize public health over profit.
Addiction
June 6, 2024
Wayne Hall, Keith Humphreys, John Marsden et al.
18 citations
The current push to broaden the production, sale, and use of psychedelics parallels the movement to legalize cannabis in the United States and other nations, notably through poorly-evidenced therapeutic claims that create a de facto recreational market via the health care system. Experience with cannabis highlights the value of debating legalization for nonmedical use directly rather than misrepresenting it as a medical issue. Lessons from cannabis policy suggest a need to challenge hype of psychedelic research findings, promote rigorous clinical research on dosing and potency, minimize for-profit industry influence, and coordinate federal, state, and local governments to regulate manufacture, sale, and distribution of psychedelic drugs.
Psychological Medicine
October 1, 2022
Wayne Hall, Keith Humphreys
18 citations
No Summary
World Psychiatry
May 18, 2021
Wayne Hall
17 citations
Psychedelic drugs such as psilocybin, LSD, and MDMA produce profound changes in thought, mood, and perception by acting on the 5-HT2A serotonin receptor. Over the past two decades, clinical research has revived, with phase 2 trials showing substantial benefits of psilocybin for treatment-resistant depression and MDMA-assisted psychotherapy for PTSD. Psilocybin has a shorter duration of action (4–6 hours) than LSD and is less likely to cause adverse reactions. A single dose can produce immediate clinical response sustained for six months in many patients, unlike standard antidepressants. However, trials have been limited to small, selected samples due to philanthropic funding constraints. Major challenges include impossibility of blinding in placebo-controlled trials and risk of off-label use outpacing evidence. Independent, publicly funded trials with larger, representative samples and longer follow-up are needed.
Addiction
May 21, 2024
Shane Darke, Johan Duflou, Amy Peacock et al.
14 citations
From 2000 to 2023 in Australia, 43 deaths involving LSD (33 cases) or psilocybin (10 cases) were identified. Most deaths were from traumatic accidents (36.4% for LSD, 40.0% for psilocybin) or self-harm by physical means (12 cases, all involving LSD). Multiple drug toxicity accounted for about a fifth of deaths. Only one death was attributed solely to LSD toxicity, and two followed a cardiovascular event after LSD use. In four psilocybin cases the cause was undetermined. Severe agitation was the most common clinical presentation. Median blood concentrations were 0.8 μg/l for LSD and 20 μg/l for psilocin. Pre-existing organ pathology was uncommon.
Addiction
August 12, 2021
Wayne Hall, Michael Farrell
8 citations
Research from the 1950s and 1960s on using LSD to treat alcohol dependence offers cautionary lessons for the current revival of psychedelic therapy. Early uncontrolled studies by Osmond and Hoffer reported that high doses of LSD induced mystical experiences that helped alcoholics embrace abstinence, with some reports claiming a 50% success rate. However, later controlled trials found no better outcomes in LSD-treated patients at 12–18 months follow-up, though a meta-analysis showed benefits up to 6 months. The history warns against irrational exuberance and emphasizes that psychedelics are not standalone cures; they require combination with aftercare and rigorous clinical trials before widespread use.
Journal of hazardous materials
September 5, 2024
Shuo Chen, Richard Bade, Ben Tscharke et al.
6 citations
Methamphetamine use in Melbourne was increasing before the first lockdown in 2020 and decreased after it ended. During the second lockdown, methamphetamine trends remained steady before rising steeply after restrictions lifted. Cocaine use stayed steady for most of 2020 and increased after the second lockdown. MDMA use decreased after the first lockdown and remained low through 2020 and 2021. In 2021, stimulant use was less variable and less tied to COVID-19 restrictions than in 2020. The findings show how lockdown periods and social restrictions affected illicit stimulant consumption in one of the world's most locked-down cities.
Addiction (Abingdon, England)
July 23, 2025
Tran Thi Thanh Hue, Hieu K T Ngo, Zhe Wang et al.
2 citations
Methamphetamine use in Hanoi, Vietnam, declined significantly from a peak of 359.2 to 125.6 mg/day/1000 people between 2018 and 2023, while ketamine use rose from 149.7 to 465.9 mg/day/1000 people, becoming the most commonly used illicit drug. Cocaine and heroin remained low, and MDMA was stable. After COVID-19 restrictions eased, cocaine and codeine consumption showed statistically significant declines, whereas ketamine and heroin increased slightly but not significantly. Wastewater analysis of a canal serving over 430,000 people reveals a dynamic drug market shifting toward synthetic substances, with ketamine overtaking methamphetamine as the most used drug by end of 2022.
The International journal on drug policy
August 1, 2026
Myfanwy Graham, Yimin Ge, Rosalie Liccardo Pacula et al.
1 citation
An estimated 19% of adults in Canada, the United States, Australia, and New Zealand have used psilocybin, LSD, MDMA, or ketamine at some point in their lives. Psilocybin was the most commonly used substance, with lifetime use highest in Canada (16.3%), followed by the US (13.0%) and New Zealand (12.1%), and lowest in Australia (7.8%). Among those who had ever used a psychedelic, 10-20% had asked their medical provider about medical use, and over a third of past-year users reported experiencing an adverse health effect. Past-month use was low across all countries. Consumer interest in therapeutic use has outpaced clinical trials and therapeutic provisions, and many people use these substances outside regulated pathways, which may increase the risk of adverse events.