Psychedelic therapy — the metamorphosis of mental health care

To view psychedelic therapy as just another psychiatric drug intervention, would be to mistake the profound paradigm shift ushered in by psychedelic science.

Photo by Evie Shaffer on Unsplash

10 years ago, if someone told you of a medicine that you need only take once to instantly relieve your depression, you would most likely have been deeply skeptical. If they had gone further, and claimed that this relief could last for weeks, months, years, or even a lifetime, your scepticism would most likely have turned to derision.

I faced such scepticism myself whilst taking my first steps into what is now more broadly known as ‘psychedelic research’ — the scientific study of psychedelic drugs, or ‘psychedelics’¹, and their therapeutic potential. Today things have changed. Increasing numbers of clinical studies provide evidence for exactly this: one or two psychedelic drug experiences can facilitate quick and sustained relieve from tobacco addiction ¹, alcohol addiction ² ³, post-traumatic stress disorder (PTSD) ⁴ ⁵ ⁶ ⁷, depression ⁸ ⁹ and end-of-life anxiety ¹⁰ ¹² ¹³ ¹⁴ (the list is growing).

However, it is critical to emphasise that this therapeutic approach, known as ‘psychedelic therapy’², is not as simple a procedure as some sensationalist headlines may suggest. Care-seekers are not simply administered the psychedelic to achieve an instant and somewhat miraculous improvement in wellbeing.

Psychedelic drug experiences are sandwiched between a number of psychotherapy sessions designed to prepare the individual for the experience. The experience itself is then carefully processed and integrated during follow up psychotherapeutic care. Whats more, the psychedelic sessions themselves last up to 8 hours, taking place in a specially designed non-clinical environment. Whilst wearing an eye mask, each individual listens to a carefully designed series of musical programs ¹⁴ ¹⁵ ¹⁶, and receives person-centred support from trained psychotherapists.

Care-seekers are not simply administered the psychedelic and achieve an instant and somewhat miraculous improvement in wellbeing

Given the large number of different variables present in this approach, much more research is needed to define exactly how this approach works. Yet, important clues are emerging from increasing numbers of independent research groups, giving rise to a growing consensus in the field: it is not the drug, but the particular experience that the drug can facilitate, that relates to the positive therapeutic outcomes reported by an increasing numbers of studies ¹² ¹³ ¹⁷ ¹⁸ ¹⁹ ²⁰.

To view psychedelic therapy as yet another psychiatric drug intervention, would be a grave mistake. The distinctness of the method amongst modern practices is where its significance lies. The unprecedented outcomes possible give us hope that this renaissance marks a breakthrough in the way we understand and treat mental health.

Mental health care is in dire need of innovation: for depression alone treatment efficacy has not improved for 70 years ²¹, only 30% respond to first-line treatments, 30% do not respond to any treatment at all ²², and the global economic burden runs into the trillions ²³ ²⁴ — let alone the immense amount of chronic human suffering that remains unresolved.

It is not the drug, but the particular experience that the drug can facilitate, that relates to the positive therapy outcomes reported by increasing numbers of studies.

Going one step further, it is possible that consistent observation in psychedelic therapies — experience as the foundation for personal transformation — may not in fact be so mysterious. Despite being novel in terms of modern mental health care, it may well be aligned with our current understanding of the neuroscience of human development.

In this series of short articles, I aim to demystify psychedelic research step-by-step. I will provide a constructive critique on developments in the field and argue that psychedelic therapy should be viewed not as a potential destination, but as a promising direction into a radically new approach to mental health and wellbeing, one that reaches beyond the use of psychedelic drugs. This new approach has the potential to not only be more effective, but more humane, more evidence-based, and –yes- much more rewarding.

By Mendel Kaelen
Psychedelic researcher, neuroscientist and founder of Wavepaths.


1. The word psychedelic is derived from the Greek words psychḗ meaning “mind” or “soul”, and dêlos, meaning “to manifest” or “make visible”. Compounds considered “classic” psychedelics include psilocybin (the psychoactive constituent of magic mushrooms), LSD, mescaline (the psychoactive constituent of peyote and san pedro cacti) and DMT (a major psychoactive ingredient in the Amazonian brew ayahuasca). All these drugs share the property of activating the serotonin 2A receptor and have phenomenological similarities.

2. Broadly speaking, by the 1960’s two distinct therapeutic approaches with psychedelics had evolved: the “psycholytic” method, mainly practiced in Europe, and the “psychedelic” method, mainly practiced in the United States. These approaches differed in the dosages administered, the amount of sessions conducted, the theoretical frameworks used, and the structure of the sessions themselves. Psycholytic therapy was characterised by lower dosages, with the intention to preserve sufficient “ego-functioning” for the patient in order to actively engage with the therapist during the sessions. Generally speaking, the primary goal here was to use the drug as an adjunct to psychotherapy. Typically, patients underwent multiple sessions to reach the therapeutic objectives. Music was used in psycholytic approaches, but more frequently intermitted by conversations or periods of silence. Psychedelic therapy was characterised by higher dosages, with the intention to dissolve “ego-functioning”, and for the individual to “immerse” fully in the unfolding experience. The primary goal here was to facilitate a “peak experience” that would result in enduring changes in personality, mood and behaviour. Typically, patients underwent one or a small number of sessions, and would listen to music for the majority of the time during these sessions. All modern studies today so far have implemented a psychedelic therapy approach.


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