Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2006 Aug:189:173-9.
doi: 10.1192/bjp.bp.105.015263.

Psychological effects of ketamine in healthy volunteers. Phenomenological study

E Pomarol-Clotet  1 , G D Honey, G K Murray, P R Corlett, A R Absalom, M Lee, P J McKenna, E T Bullmore, P C Fletcher
Affiliations

Psychological effects of ketamine in healthy volunteers. Phenomenological study

E Pomarol-Clotet et al. Br J Psychiatry. 2006 Aug.

Abstract

Background: The psychosis-inducing effect of ketamine is important evidence supporting the glutamate hypothesis of schizophrenia. However, the symptoms the drug produces have not been described systematically.

Aim: To examine the effects of ketamine in healthy people using a structured psychiatric interview.

Method: Ketamine (200 ng/ml) or placebo was administered by continuous infusion to 15 healthy volunteers. Symptoms were rated using the Present State Examination, the Thought, Language and Communication Scale and the Scale for Assessment of Negative Symptoms.

Results: Ketamine induced a range of perceptual distortions, but not hallucinations. Referential ideas were seen in nearly half the sample. There were only mild and infrequent ratings on the thought disorder scale. Affective flattening and alogia were seen in some volunteers.

Conclusions: Ketamine does not reproduce the full picture of schizophrenia. The main point of similarity concerns referential thinking. Phenomena resembling negative symptoms are also seen, but the distinction of these from the drug's sedative effects requires further elucidation.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
Mean CADSS scores for15 volunteers receiving ketamine or placebo. 0=not at all, 1=slightly, 2=moderately, 3=considerably, 4=extremely. CADSS, Clinician Administered Dissociative States Scale.
See this image and copyright information in PMC

Comment in

References

    1. Adler CM, Goldberg TE, Malhotra AK, et al. Effects of ketamine on thought disorder, working memory and semantic memory in healthy volunteers. Biological Psychiatry. 1998;43:811–816. - PubMed
    1. Adler CM, Malhotra AK, Elman I, et al. Comparison of ketamine-induced thought disorder in healthy volunteers and thought disorder in schizophrenia. American Journal of Psychiatry. 1999;156:1646–1649. - PubMed
    1. Andreasen NC. Negative symptoms in schizophrenia: definition and reliability. Archives of General Psychiatry. 1982;39:784–788. - PubMed
    1. Andreasen NC. The Comprehensive Assessment of Symptoms and History. University of Iowa College of Medicine; Iowa City, IA: 1987.
    1. Bowdle TA, Radant AD, Cowley DS, et al. Psychedelic effects of ketamine in healthy volunteers: relationship to steady-state plasma concentrations. Anesthesiology. 1998;88:82–88. - PubMed

MeSH terms