Harm Reduction

In the Fundamentals of Psychedelic-Assisted Therapy course, we looked at the overall harm of hallucinogenic substances compared with other common substances of abuse. If you haven’t yet taken Fundamentals, we have provided sufficient context below.

In the course, we learned that a landmark study published in the Lancet in 2010 examined the individual, societal, and global harms associated with 20 commonly used substances.

The chart below is interactive. Click the coloured boxes in the legend to toggle between seeing the values together or separately.

Adapted from Lancet, 2010.

Classical psychedelics, like psilocybin, are known to have extremely low toxicity and dependence risk, as well as limited physical, psychological, and social risks. In some cases, their use has also been linked with reduced psychological distress and suicidality (Gable, 1993; Gable, 2006; Hendricks et al., 2015; Johansen & Krebs, 2015; Johnson et al., 2008; Nichols, 2004; Nutt et al., 2010; Passie et al., 2002).

Overall, the risk of serious adverse effects has been shown to be low (Carhart-Harris et al., 2016; Johnson et al., 2008; Metzner, 2005). However, below are some key risks that health professionals should be mindful of when working with clients undergoing psilocybin-assisted therapy.

Please ensure that you read through all items before proceeding by selecting each title.

Some have theorized that extremely high doses of psilocybin may potentially contribute to issues with hypertension and tachycardia in predisposed individuals, causing coma, hyperthermia, and respiratory failure; this, however, is only speculation and is theorized based upon doses of psilocybin several times larger than those used in clinical trials (Klock et al., 1975). For individuals who microdose psilocybin or magic mushrooms, there is a potential risk of valvular heart disease with chronic microdosing (Thomas, 2019).

There are also ongoing concerns in relation to the potential for lasting negative adverse effects related to anxiety, paranoia, dissociation, and hallucinogen persisting perception disorder (HPPD) (Strassman, 1984). HPPD is thought to occur in only a few cases out of each million users (Johnson et al., 2008).

Prolonged psychosis in otherwise healthy subjects, for example, is linked to predisposition in most cases (Johnson et al., 2008). In another study of 227 psilocybin administrations where participants were carefully selected, 7% of participants experienced acute psychotic reactions (Studerus et al., 2010).

It is important to note that incidences of medical troubles arising from the use of psilocybin are generally linked to accidents as a result of behavioural alterations when dosing occurs in non-medical settings. This underlines the value of an experienced health professional for treatment when using psilocybin and the importance of psychedelic-assisted therapy as a method for employing this medicine (Johnson et al., 2008; Leary et al., 1963).

Particularly with the medicines used in psychedelic-assisted therapy, clients may start treatment with some inaccurate information about the psychedelic medicine being used. The internet (particularly social media platforms) is full of misinformation about psychedelic medicines, their effects, adverse effects, and anticipated experiences.

  • Psilocybin will cure your [insert mental health issue/concern here]

  • Psilocybin is a short experience (akin to ketamine duration)

  • Psilocybin-assisted therapy is with a regular microdose

  • Psilocybin is “natural” so it can replace SSRIs

  • Unawareness of aftereffects of psilocybin (perhaps more so the physical sensations)

  • Psilocybin-assisted therapy is dosed with raw material (magic mushrooms)

  • Psilocybin is legal for use in Canada

  • Psilocybin-assisted therapy is free because it is all done through clinical trials and is covered by the government

References

Carhart-Harris, R. L., Bolstridge, M., Rucker, J., Day, C. M., Erritzoe, D., Kaelen, M., . . . Nutt, D. J. (2016). Psilocybin with psychological support for treatment-resistant depression: an open-label feasibility study. Lancet Psychiatry, 3(7), 619-627. https://doi.org/10.1016/S2215-0366(16)30065-7

Gable, R. S. (1993). Toward a comparative overview of dependence potential and acute toxicity of psychoactive substances used nonmedically. Am J Drug Alcohol Abuse, 19(3), 263-281. https://doi.org/10.3109/00952999309001618

Gable, R. S. (2006). The Toxicity of Recreational Drugs. American Scientist, 94, 206-208.

Hendricks, P. S., Thorne, C. B., Clark, C. B., Coombs, D. W., & Johnson, M. W. (2015). Classic psychedelic use is associated with reduced psychological distress and suicidality in the United States adult population. J Psychopharmacol, 29(3), 280-288. https://doi.org/10.1177/0269881114565653

Johansen, P., & Krebs, T. S. (2015). Psychedelics not linked to mental health problems or suicidal behavior: a population study. J Psychopharmacol, 29(3), 270-279. https://doi.org/10.1177/0269881114568039

Johnson, M., Richards, W., & Griffiths, R. (2008). Human hallucinogen research: guidelines for safety. J Psychopharmacol, 22(6), 603-620. https://doi.org/10.1177/0269881108093587

Klock, J. C., Boerner, U., & Becker, C. E. (1975). Coma, hyperthermia, and bleeding associated with massive LSD overdose, a report of eight cases. Clin Toxicol, 8(2), 191-203. https://doi.org/10.3109/15563657508988063

Leary, T., Litwin, G. H., & Metzner, R. (1963). Reactions to psilocybin administered in a supportive environment. Journal of Nervous and Mental Disease, 137(6), 561-573. https://doi.org/10.1097/00005053-196312000-00007

Metzner, R. (2005). Sacred Mushrooms of Visions: Teonanácatl: A Sourcebook on the Psilocybin Mushroom. Park St. Press.

Nichols, D. E. (2004). Hallucinogens. Pharmacol Ther, 101(2), 131-181. https://doi.org/10.1016/j.pharmthera.2003.11.002

Nutt, D. J., King, L. A., Phillips, L. D., & Drugs, I. S. C. o. (2010). Drug harms in the UK: a multicriteria decision analysis. Lancet, 376(9752), 1558-1565. https://doi.org/10.1016/S0140-6736(10)61462-6

Passie, T., Seifert, J., Schneider, U., & Emrich, H. M. (2002). The pharmacology of psilocybin. Addict Biol, 7(4), 357-364. https://doi.org/10.1080/1355621021000005937

Strassman, R. J. (1984). Adverse reactions to psychedelic drugs. A review of the literature. J Nerv Ment Dis, 172(10), 577-595. https://doi.org/10.1097/00005053-198410000-00001

Studerus, E., Kometer, M., Hasler, F., & Vollenweider, F. X. (2011). Acute, subacute and long-term subjective effects of psilocybin in healthy humans: a pooled analysis of experimental studies. Journal of psychopharmacology (Oxford, England), 25(11), 1434–1452. https://doi.org/10.1177/0269881110382466

Thomas, K. (2019). Why Chronic Microdosing Might Break Your Heart. Chacruna. https://chacruna.net/why-chronic-microdosing-might-break-your-heart/