Psychedelic medicine: a re-emerging therapeutic paradigm

In clinical research settings around the world, renewed investigations are taking place on the use of psychedelic substances for treating illnesses such as addiction, depression, anxiety and posttraumatic stress disorder (PTSD). Since the termination of a period of research from the 1950s to the early 1970s, most psychedelic substances have been classified as “drugs of abuse” with no recognized medical value. However, controlled clinical studies have recently been conducted to assess the basic psychopharmacological properties and therapeutic efficacy of these drugs as adjuncts to existing psychotherapeutic approaches. Central to this revival is the re-emergence of a paradigm that acknowledges the importance of set (i.e., psychological expectations), setting (i.e., physical environment) and the therapeutic clinician-patient relationship as critical elements for facilitating healing experiences and realizing positive outcomes.The public is often well-versed in the potential harms of psychedelic drugs, but much of this knowledge is from cases involving patients who used illicit substances in unsupervised nonmedical contexts. We discuss the emerging research for therapeutic purposes involving human subjects, considering both the possible benefits and the potential harms of using psychedelic agents as adjuncts to psychotherapy or counselling for mental illness.