Tier 2 — strong

Adjunctive high-dose glycine in the treatment of schizophrenia

Javitt DC, Silipo G, Cienfuegos A, Shelley AM, Bark N, Park M, Lindenmayer JP, Suckow R, Zukin SR
The international journal of neuropsychopharmacology 2001 4(4):385-391

Bibliography

PubMed
PMID 11806864
DOI
10.1017/s1461145701002590
Funding
Indexed support: NIMH NIH HHS. See the publication for grant and funder details.
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
Sample12 additional adults with schizophrenia
InterventionAdjunctive high-dose glycine, 0.8 g/kg/day, versus placebo alongside antipsychotic treatment
Duration6-week crossover periods
EndpointsNegative symptoms; Serum glycine; Antipsychotic concentrations

What the study showed, in plain terms

This small adjunctive study reported symptom improvement without a significant change in antipsychotic drug concentrations. It examined whether altered medication levels could explain earlier clinical signals.

Key findings

  • Negative symptoms decreased by a reported 34% during glycine treatment.
  • Serum antipsychotic concentrations did not significantly change.

What this study can and cannot tell us

Small clinical crossover study; positive early findings were not consistently replicated at scale.

Persistence of improvement after discontinuation complicates crossover interpretation.

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Editorial review

Reviewed by the Biohack Blueprint research team

Last verified

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