Hallucinogenic drugs in psychiatric research and treatment: perspectives and prospects

Introduction

The review situates contemporary human research with hallucinogens against a long history of cultural, recreational, and clinical use. Earlier work with lysergamides (notably LSD), phenethylamines (mescaline), and indolealkylamines (psilocybin, DMT) generated substantial clinical and psychopharmacological data in the mid-20th century but was interrupted for about a generation. The author emphasises three motivations for renewed research: (1) hallucinogens produce complex syndromes that probe many aspects of human cognition, affect, perception, and volition and so offer a window on mind–brain relationships; (2) drug-induced states overlap in some respects with endogenous psychoses, suggesting potential mechanistic and therapeutic insights; and (3) reports of psychotherapeutic enhancement, and continued recreational use and abuse, argue for better-characterised, safe clinical research and treatments for adverse sequelae. This article therefore aims to review the history, pharmacology, human experimental data, therapeutic applications, adverse effects, and regulatory context of classical and related hallucinogens, and to outline methodological, training, and future-research priorities for restarting human hallucinogen research. The author frames the review as both a synthesis of existing human data and a set of pragmatic recommendations for designing rigorous, state-of-the-art studies in the 1990s and beyond.