Anxiety DisordersDepressive DisordersLSD

Chronic administration of serotonergic antidepressants attenuates the subjective effects of LSD in humans

This interview study (n=32) investigated the effects of antidepressants on self-administered LSD. 28 participants who had been taking SSRIs for over 3 weeks reported a subjective decreased response to LSD.

Authors

  • Bonson, K. R.

Published

Neuropsychopharmacology
individual Study

Abstract

This study investigates the possible interactions of antidepressant agents and hallucinogens in humans through structured interviews using a standardized questionnaire. Volunteer subjects recruited through announcements placed on the Internet or other sources were asked to describe the somatic, hallucinatory, and psychological effects of self-administered LSD prior to and during chronic administration of an antidepressant. Twenty-eight out of 32 subjects (88%) who had taken an antidepressant with inhibitory effects on serotonin (5-HT) reuptake (fluoxetine, paroxetine, sertraline, trazodone) for over 3 weeks had a subjective decrease or virtual elimination of their responses to LSD. An additional subject who had taken fluoxetine for only 1 week had an increased response to LSD. These data are in contrast to our previous study that reported increased responses to LSD during chronic administration of tricyclic antidepressants or lithium. Possible mechanisms of action for the effects from serotonergic antidepressants involve 5-HT2 and 5-HT1A receptors, changes in extracellular brain serotonin concentrations, and changes in brain catecholamine systems.

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Research Summary of 'Chronic administration of serotonergic antidepressants attenuates the subjective effects of LSD in humans'

Introduction

Bonson frames the study around a practical concern: many people use both prescribed antidepressants and recreational hallucinogens, yet interactions between these drug classes have received limited systematic study. Earlier clinical observations showed that chronic monoamine oxidase inhibitors (MAOIs) could markedly attenuate subjective responses to LSD, while tricyclic antidepressants or lithium had been reported to potentiate LSD's effects. A single prior case report also suggested that the selective serotonin reuptake inhibitor (SSRI) fluoxetine might reduce LSD's hallucinogenic effects. Given these mixed and sparse data, the authors identify a gap in understanding how chronically administered serotonergic antidepressants influence the human subjective response to LSD. This paper reports a retrospective, questionnaire-based investigation that sought to characterise changes in somatic, hallucinatory and psychological effects of self-administered LSD when users were concurrently taking physician-prescribed serotonergic antidepressants. The primary aim was to determine whether chronic treatment with serotonin reuptake inhibitors (SRIs; examples in the sample include fluoxetine, sertraline, paroxetine and trazodone) was associated with attenuation, enhancement or no change in the subjective effects of LSD compared with the subjects' prior or contemporaneous control experiences.

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Study Details

  • Study Type
    individual
  • Journal
  • Compound
  • Topics
  • APA Citation

    Bonson, K. (1996). Chronic administration of serotonergic antidepressants attenuates the subjective effects of LSD in humans. Neuropsychopharmacology, 14(6), 425-436. https://doi.org/10.1016/0893-133x(95)00145-4

References (1)

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