Harnessing placebo: Lessons from psychedelic science

Introduction

Earlier research has shown that contextual, interpersonal and cultural variables — commonly labelled the placebo effect — can contribute substantially to treatment outcomes and sometimes rival the magnitude of drug-specific effects observed in randomized controlled trials (RCTs). However, translating knowledge about placebo mechanisms into routine clinical practice has been limited by conceptual confusion (for example, whether placebo effects are "real" physiological phenomena or merely psychological artefacts) and normative concerns about deception and medical paternalism. The authors trace this tension back to historical uses of placebos in the clinic (as pragmatic tools to placate or reassure patients) versus their later epistemic role in research (as controls used to isolate drug-specific effects). They argue that these divergent histories have shaped persistent misunderstandings about what placebo effects are and how they should be handled in medicine. Pronovost-Morgan and colleagues set out to clarify the conceptual foundations of placebo phenomena and to propose practical ways to harness extra-pharmacological variables ethically for patient benefit. They draw on the psychedelic-science concept of "set and setting" — the person-level mindset and the physical/social/cultural environment surrounding drug administration — as a generative framework that reframes placebo ingredients as interactive, synergistic contributors to treatment efficacy rather than mere nuisance variables to be subtracted out. The paper aims to map historical and contemporary placebo theory onto psychedelic research findings and, from that synthesis, offer translational recommendations for clinicians and researchers seeking to integrate nondrug variables into biomedical practice.