Tier 2 — strong

Adjunctive glycine in the treatment of obsessive-compulsive disorder in adults

Greenberg WM, Benedict MM, Doerfer J, Perrin M, Panek L, Cleveland WL, Javitt DC
Journal of psychiatric research 2009 43(6):664-670

Bibliography

PubMed
PMID 19046587
DOI
10.1016/j.jpsychires.2008.10.007
Trial registry
View on ClinicalTrials.gov Registered trial — results not yet published in a peer-reviewed journal.
Funding
Funding was not specified in the indexed abstract; the full funding disclosure has not been verified.
Competing interests
The accessible abstract does not establish the authors' competing interests; absence of a statement is not evidence of no conflicts.

Study snapshot

DesignRandomized controlled human intervention
ModelAdult humans
Sample24 randomized; 14 evaluable, including 5 glycine and 9 placebo
InterventionAdjunctive glycine titrated to 60 g/day versus placebo
Duration12 weeks
EndpointsYale-Brown Obsessive Compulsive Scale; Adherence; Nausea and palatability

What the study showed, in plain terms

An OCD trial produced an uncertain symptom signal and substantial dropout. Tolerability and adherence at very high doses were major practical limitations.

Key findings

  • The main modeled comparison narrowly missed conventional statistical significance, P=0.053.
  • Only fourteen participants met the evaluation criteria, with more attrition in the glycine arm.
  • Taste and nausea contributed to nonadherence.

What this study can and cannot tell us

Small final sample, differential dropout and borderline estimates prevent an efficacy conclusion.

This dose cannot be treated as a routine supplement recommendation.

Related papers in the corpus

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The Cognitive and Negative Symptoms in Schizophrenia Trial (CONSIST): the efficacy of glutamatergic agents for negative symptoms and cognitive impairments
Buchanan RW et al. · The American journal of psychiatry · 2007
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Effect of clozapine and adjunctive high-dose glycine in treatment-resistant schizophrenia
Potkin SG et al. · The American journal of psychiatry · 1999
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High-dose glycine added to olanzapine and risperidone for the treatment of schizophrenia
Heresco-Levy U et al. · Biological psychiatry · 2004
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Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia
Heresco-Levy U et al. · Archives of general psychiatry · 1999
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Double-blind, placebo-controlled, crossover trial of glycine adjuvant therapy for treatment-resistant schizophrenia
Heresco-Levy U et al. · The British journal of psychiatry : the journal of mental science · 1996
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Amelioration of negative symptoms in schizophrenia by glycine
Javitt DC et al. · The American journal of psychiatry · 1994

Editorial review

Reviewed by the Biohack Blueprint research team

Last verified

Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction