I recently finished Michael Pollan's new book "How to change your mind". The book is about the re-emergence of psychedelics and especially the resurgence of research around their use in medicine. Psychedelics are being explored as alternative treatments for particular conditions (i.e. PTSD or end-stage cancer) but also are being tested in studies not obviously focused on disease but instead general human growth and development. This point can be illustrated by a 2006 study at Johns Hopkins titled “Psilocybin Can Occasion Mystical-Type Experiences Having Substantial and Sustained Personal Meaning and Spiritual Significance.”
One of the many subjects of the book is how psychedelics are very different than most pharmaceuticals in that their effect is highly reliant on "set and setting". As explained by Pollan:
Set is the mind-set or expectation one brings to the experience, and setting is the environment in which it takes place. Compared with other drugs, psychedelics seldom affect people the same way twice, because they tend to magnify whatever’s already
going on both inside and outside one’s head.
Taking an ipurpofen meanwhile for your headache should have more or less the same effect regardless of your mood and your setting. According to Pollan this is one of the unique aspects of psychedelic research - that it partially acts as a catalyst or amplifier and hence is hard to study psychedelics in and of themselves in terms of particular clinical outcomes.
To make a bad joke then, psychedelics can be thought of as placebos on steroids. Ha.
I think it is worth pointing out that while this may be an usual situation in pharmaceutical research it is not without precedent in research generally. There is often more than one 'active ingredient' in other forms of research.
Take an evaluation of a Montessori school. No seasoned evaluator would believe that adoption of the Montessori method and philosophy would be the only factor to consider in assessing the effectiveness of Montessori schools. Numerous other factors matter: the educational leadership, the characteristics of the teaching staff, student composition, etc.
Research on psychedelics then may be messier than with other pharmaceuticals but hardly presents research challenges exceeding those typically encountered by researchers in social science.
What research on psychedelics does challenge is the very nature of FDA approval and medical research - guidelines that approve the use of pharmaceutical substances to treat a particular disease. What is the 'disease' that a drug that "occassions mystical-type experiences" addresses? Is it a disease or more of a dis-ease?
Griffiths, R.R., Richards, W.A., McCann, U. et al. Psychopharmacology (2006) 187: 268. https://doi.org/10.1007/s00213-006-0457-5