A critical review of reports of endogenous psychedelic N, N-dimethyltryptamines in humans: 1955-2010

Introduction

Barker and colleagues review the long-standing question of whether three tryptamine derivatives—N,N-dimethyltryptamine (DMT), 5-hydroxy-DMT (bufotenine, HDMT), and 5-methoxy-DMT (MDMT)—are endogenous in humans. Earlier research used a variety of analytical approaches as instrumentation evolved, and interest in these compounds has been driven both by their psychedelic properties and by recent findings that DMT interacts with molecular targets such as the sigma-1 receptor and trace amine receptors. The potential physiological or pathophysiological roles of these compounds have been discussed in relation to altered states of consciousness, psychiatric conditions (notably psychosis and schizophrenia), dreams, religious experiences and ayahuasca use, but no definitive biological role has been established. This review sets out to critically evaluate 69 published studies from 1955 to 2010 that report detection or quantitation of DMT, HDMT and MDMT in human body fluids (blood, urine and cerebrospinal fluid). The investigators examine the analytical methods and identification criteria applied across studies, summarise reported detection rates and concentration ranges, and highlight methodological strengths and weaknesses with the aim of clarifying which findings are reliable and which require further confirmation. They also outline questions for future research, including the origin, metabolism and optimal sampling strategies for these compounds.