Understanding the Risks: What Hospital Data Reveals About Psychedelic Use

In recent years, psychedelics have experienced a remarkable rehabilitation in both scientific and public perception. Once dismissed as dangerous drugs of abuse, compounds like psilocybin, LSD, and MDMA are now being rigorously studied for their potential to treat conditions ranging from depression to PTSD. Headlines tout "breakthrough therapy" designations and promising clinical trial results, creating a narrative of psychedelics as wonder drugs with minimal risks. But a sobering new study from Canadian researchers offers an important counterbalance to this enthusiasm. The research, published in the Canadian Medical Association Journal, found that people who required emergency hospital care for hallucinogen use faced a 2.6-fold higher risk of death within five years compared to the general population. This finding doesn't negate the therapeutic potential of psychedelics in controlled settings. Rather, it highlights the crucial distinction between supervised medical use and recreational or self-administered use—a distinction that often gets blurred in popular discussions of these powerful substances.

The Canadian Hospital Study: What the Data Shows

The research team, led by Dr. Daniel Myran, conducted a comprehensive retrospective cohort study using linked health administrative data on all people aged 15 years and older living in Ontario, Canada, from 2006 to 2022. They compared mortality rates between the general population and people who had emergency department visits or hospital admissions involving hallucinogens. The results were striking. In a matched analysis with 77,101 people followed for a median of 7 years, those who had received acute care involving hallucinogens showed a 2.6-fold increased risk of death within 5 years compared to the general population. In absolute terms, this translated to a 6.1% risk of death among those with hallucinogen-related hospital visits versus 0.6% in the general population. "While clinical trials involving psychedelic-assisted psychotherapy have not observed short-term increases in the risk of death, limited data exist on mortality associated with hallucinogen use outside of controlled trial settings," the researchers noted. Their study helps fill this critical knowledge gap. Importantly, the elevated mortality risk persisted even when researchers excluded people with comorbid mental health or substance use disorders from the analysis. This suggests that the increased risk isn't simply due to these pre-existing conditions but may be related to the circumstances or consequences of hallucinogen use itself. The study also examined specific causes of death, finding that people with hallucinogen-related hospital visits had significantly elevated risks of death from:

•Unintentional drug poisoning (2.03 times higher risk)

•Suicide (5.23 times higher risk)

•Respiratory disease (2.46 times higher risk)

•Cancer (2.88 times higher risk)

The particularly high risk of suicide is especially concerning and warrants further investigation. It raises questions about whether certain vulnerable individuals might experience psychological after-effects from challenging psychedelic experiences that contribute to suicidal behavior.

Understanding Correlation vs. Causation

Before drawing conclusions from these findings, it's essential to understand a fundamental principle of epidemiological research: correlation does not necessarily imply causation. The fact that people who had hallucinogen-related hospital visits died at higher rates doesn't prove that the hallucinogens caused these deaths. Several alternative explanations could account for this correlation:

Selection bias: People who end up in emergency rooms after hallucinogen use may differ in important ways from both the general population and from people who use hallucinogens without requiring medical attention. They might engage in more risk-taking behaviors generally or have underlying health vulnerabilities.

Confounding factors: Despite the researchers' efforts to control for variables like mental health and substance use disorders, other unmeasured factors might contribute to both hallucinogen-related emergencies and increased mortality.

Reverse causality: In some cases, people might use hallucinogens as a form of self-medication for conditions or distress that themselves increase mortality risk.

Polysubstance use: Many people who use hallucinogens also use other substances, and these patterns of multiple drug use might contribute to adverse outcomes.

Dr. Marco Solmi, one of the study's co-authors, acknowledges these limitations: "Our study identifies an important association, but we need to be careful about attributing causality. What we can say with confidence is that requiring emergency care for hallucinogen use identifies a population at significantly higher risk of premature death who might benefit from targeted interventions."

Risk Factors and Vulnerable Populations

The study's findings highlight the importance of understanding who might be at particular risk for adverse outcomes from hallucinogen use. Several factors appear to increase vulnerability:

Pre-existing psychiatric conditions: People with conditions like bipolar disorder, schizophrenia, or personality disorders may be at higher risk for psychotic reactions or psychological decompensation with hallucinogen use.

Family history of psychosis: Genetic vulnerability to psychotic disorders may increase the risk of triggering latent conditions.

Developmental age: Adolescents and young adults, whose brains are still developing, may be particularly vulnerable to adverse effects.

Setting and supervision: Unsupervised use in chaotic or threatening environments significantly increases the risk of adverse reactions.

Dosage and frequency: Higher doses and frequent use patterns may increase risks, particularly when tolerance and cross-tolerance factors aren't well understood by users.

Medication interactions: Certain medications, particularly serotonergic drugs like SSRIs, can interact dangerously with some hallucinogens.

Jules Evans, lead author of a consensus paper on psychedelic safety, emphasizes the importance of recognizing these risk factors: "As usage of psychedelic drugs increases in some countries, and national and local authorities consider bills to legalize or decriminalize their access, it is important to learn more about psychedelic risks, communicate them more accurately, prevent them where possible, and support those who experience adverse events."

Clinical vs. Non-Clinical Use: A Critical Distinction

The stark contrast between the safety profile of psychedelics in clinical trials and the elevated mortality risk found in this population-based study highlights the crucial importance of context and supervision in determining outcomes. In clinical trials of psychedelic-assisted therapy, several protective factors are in place:

Careful screening: Participants undergo thorough medical and psychological screening to exclude those with contraindications or high-risk profiles.

Controlled dosing: Pure substances are administered in precisely measured doses.

Supportive setting: Sessions take place in comfortable, controlled environments designed to minimize anxiety and adverse reactions.

Professional supervision: Trained therapists remain present throughout the experience to provide support and intervention if needed.

Integration support: Structured follow-up sessions help participants process and integrate their experiences. These safeguards are largely absent in recreational or self-administered use, where individuals may:

•Be unaware of personal risk factors

•Consume substances of unknown purity and potency

•Use in suboptimal settings without adequate support

•Lack preparation and integration resources

•Combine hallucinogens with other substances

"The context of use matters enormously," explains Dr. Peter Hendricks, a researcher studying psychedelic therapies. "The same substance that shows remarkable therapeutic potential in a carefully controlled clinical setting can pose significant risks when used in uncontrolled circumstances, particularly for vulnerable individuals."

The Safety Net for Psychedelic Use

The researchers behind the Canadian study and other experts in the field emphasize that their findings shouldn't be used to demonize psychedelics or halt promising research. Rather, they highlight the need for a more robust safety net as these substances become more widely used. Several approaches could help reduce risks:

Better education: Accurate, nuanced information about both potential benefits and risks of psychedelics can help individuals make informed decisions.

Harm reduction resources: Practical guidance on safer use practices, including dosage, setting, and trip sitting, can reduce adverse outcomes.

Integration support: Greater availability of resources to help people process challenging psychedelic experiences might prevent long-term psychological difficulties.

Crisis services: Specialized support for those experiencing acute psychological distress related to psychedelics could reduce emergency room visits and their associated risks.

Research on adverse effects: More systematic study of negative outcomes can help identify risk factors and develop better screening tools.

A consensus paper from 30 psychedelic harm researchers published in Psychiatric Research and Clinical Practice outlines several critical research gaps that need addressing, including better understanding of the types and predictors of psychedelic harms and more effective approaches to treating adverse effects. The authors call for better support for those experiencing post-psychedelic difficulties, including improved online information, peer support groups, affordable therapy, and psychiatric consultation when needed. They also suggest that psychedelic companies and investors should commit 1% of their funding to supporting safety measures such as research and support services.

Balancing Potential Benefits with Risks

The emerging picture of psychedelics is one of powerful tools with both significant therapeutic potential and meaningful risks that vary substantially based on context, individual factors, and use patterns. For individuals considering psychedelic use, this nuanced understanding suggests several considerations:

Medical supervision: For those seeking therapeutic benefits, medically supervised contexts offer the safest approach, though access remains limited in many jurisdictions.

Personal risk assessment: Understanding one's own risk factors, including family history of psychosis, current mental health status, and medication use, is essential.

Harm reduction: For those who choose to use psychedelics outside medical settings, harm reduction practices like having a sober sitter, starting with low doses, and creating a safe environment can minimize risks.

Integration resources: Having support for processing experiences, particularly challenging ones, may help prevent long-term adverse psychological effects.

Recognition of warning signs: Knowing when to seek help for persistent psychological difficulties following psychedelic use is crucial.

Dr. Brian Holoyda, a psychiatrist who studies psychedelic risks, emphasizes the importance of balanced information: "We do a disservice to the public when we either exaggerate or minimize the risks of psychedelics. These are powerful compounds that deserve respect. Their therapeutic potential is exciting, but that doesn't mean they're appropriate for everyone or in every context."

Policy and Public Health Implications

The Canadian study's findings have important implications for both policy and public health approaches to psychedelics. From a policy perspective, they suggest that:

Regulatory frameworks should distinguish between medical and non-medical use, with appropriate safeguards for each context.

Decriminalization efforts should be accompanied by robust public education and harm reduction resources.

Medical use protocols should maintain rigorous screening and supervision standards even as access expands.

From a public health standpoint, the findings highlight the need for:

Targeted interventions for those who experience hallucinogen-related emergencies, given their elevated mortality risk.

Better training for emergency department staff in managing psychedelic crises with minimal trauma.

Improved monitoring of adverse events as psychedelic use increases in the general population.

Research funding directed toward understanding and mitigating risks, not just exploring benefits.

Dr. Myran, the study's lead author, notes: "These findings should be considered in clinical and policy decision-making, given the increasing use of hallucinogens and associated problematic use. However, they shouldn't be interpreted as an argument against carefully conducted research on therapeutic applications."

Conclusion

The Canadian hospital study provides a valuable counterbalance to both excessive enthusiasm and unwarranted fear regarding psychedelics. It reminds us that these powerful substances can be associated with serious risks in certain contexts and for certain individuals, even as they show promise as therapeutic tools in controlled settings. The 2.6-fold increased mortality risk among those requiring emergency care for hallucinogen use doesn't negate the potential benefits of psychedelic-assisted therapy. Rather, it underscores the importance of context, screening, supervision, and support in determining outcomes. As research continues and access potentially expands, a nuanced, evidence-based approach to both benefits and risks will best serve public health. This means neither dismissing concerns about safety nor abandoning promising therapeutic applications, but rather developing systems that maximize benefits while minimizing harms. For individuals, healthcare providers, researchers, and policymakers alike, the path forward lies in respecting both the remarkable potential and the real risks of these powerful compounds—a balanced perspective informed by the growing body of scientific evidence rather than by either enthusiasm or fear alone.

References

Myran, D. T., Xiao, J., Fabiano, N., Pugliese, M., Kaster, T. S., Rosenblat, J. D., Husain, M. I., Fiedorowicz, J. G., Wong, S., Tanuseputro, P., & Solmi, M. (2025). Mortality risk among people receiving acute hospital care for hallucinogen use compared with the general population. Canadian Medical Association Journal, 197(8), E204-E213. https://pmc.ncbi.nlm.nih.gov/articles/PMC11879370/

Evans, J., Aixalà, M., Anderson, B. T., Brennan, W., Bremler, R., Breeksema, J. J., Burback, L., Calder, A. E., Carhart‐Harris, R. L., Cheung, K., Devenot, N., Gorman, I., Greń, J., Hendricks, P. S., Holoyda, B., Jacobs, E., Krecké, J., Kruger, D. J., Luke, D., ... Yaden, D. B. (2025). On Minimizing Risk and Harm in the Use of Psychedelics. Psychiatric Research and Clinical Practice, 7(1), 4-8. https://pmc.ncbi.nlm.nih.gov/articles/PMC11956720/

News Medical. (2025, March 3). Hallucinogen use linked to increased risk of mortality in emergency care patients. News-Medical.net. https://www.news-medical.net/news/20250303/Hallucinogen-use-linked-to-increased-risk-of-mortality-in-emergency-care-patients.aspx

Disclaimer: Psychedelic Assisted Psychotherapy has not been approved by any regulatory agencies in the United States, and the safety and efficacy are still not formally established at the time of this writing.