Psychedelics and Mental Health : A Population Study, Teri S. Krebs & Pal-Ørjan Johansen, 2013

Psychedelics and Mental Health : A Population Study

Teri S. Krebs, Pal-Ørjan Johansen

PLoS ONE, 2013, 8, (8): e63972.




Background : The classical serotonergic psychedelics LSD, psilocybin, mescaline are not known to cause brain damage and are regarded as non-addictive. Clinical studies do not suggest that psychedelics cause long-term mental health problems. Psychedelics have been used in the Americas for thousands of years. Over 30 million people currently living in the US have used LSD, psilocybin, or mescaline.

Objective : To evaluate the association between the lifetime use of psychedelics and current mental health in the adult population.

Method : Data drawn from years 2001 to 2004 of the National Survey on Drug Use and Health consisted of 130,152 respondents, randomly selected to be representative of the adult population in the United States. Standardized screening measures for past year mental health included serious psychological distress (K6 scale), mental health treatment (inpatient, outpatient, medication, needed but did not receive), symptoms of eight psychiatric disorders (panic disorder, major depressive episode, mania, social phobia, general anxiety disorder, agoraphobia, posttraumatic stress disorder, and nonaffective psychosis), and seven specific symptoms of non-affective psychosis. We calculated weighted odds ratios by multivariate logistic regression controlling for a range of sociodemographic variables, use of illicit drugs, risk taking behavior, and exposure to traumatic events.

Results : 21,967 respondents (13.4% weighted) reported lifetime psychedelic use. There were no significant associations between lifetime use of any psychedelics, lifetime use of specific psychedelics (LSD, psilocybin, mescaline, peyote), or past year use of LSD and increased rate of any of the mental health outcomes. Rather, in several cases psychedelic use was associated with lower rate of mental health problems.

Conclusion : We did not find use of psychedelics to be an independent risk factor for mental health problems.



Psychedelic plants have been used for celebratory, religious or healing purposes for thousands of years [1–3]. Use of psychedelics increased in the 1960s and has remained widespread in many parts of the world ever since. Over 30 million people living in the US have used lysergic acid diethylamide (LSD), psilocybin (magic mushrooms), and mescaline (peyote and other cacti) [4]. Common reasons for using psychedelics include mystical experiences, curiosity, and introspection [5]. The classical serotonergic psychedelics are not known to cause damage to the brain or other organs of the body, or cause withdrawal symptoms, elicit addiction or compulsive use [3], or cause birth defects or genetic damage [6]. Psychedelics often elicit deeply personally and spiritually meaningful experiences and sustained beneficial effects [7–12]. Psychedelics can often cause period of confusion and emotional turmoil during the immediate drug effects [13] and infrequently such adverse effects last for a few days after use. Psychedelics are not regarded to elicit violence [14] and dangerous behavior leading to suicide or accidental death under the influence of psychedelics is regarded as extremely rare [15]. LSD and
psilocybin are consistently ranked in expert assessments as causing less harm to both individual users and society than alcohol, tobacco, and most other common recreational drugs [16–19].

Given that millions of doses of psychedelics have been consumed every year for over 40 years, well documented case reports of longterm mental health problems following use of these substances are rare. Controlled studies have not suggested that use of psychedelics lead to long-term mental health problems [8,9,13,20]. Here we evaluate the association between the use of psychedelics and mental health among US adults.