title: The effect of sodium nitroprusside on psychotic symptoms and spatial working memory in patients with schizophrenia: a randomized, double-blind, placebo-controlled trial.
abstract: Sodium nitroprusside (SNP) has been reported to rapidly reduce psychotic symptoms in patients with schizophrenia. This has the potential to revolutionize treatment for schizophrenia. In this study, we tested the hypothesis that SNP leads to a reduction in psychotic symptoms and an improvement in spatial working memory (SWM) performance in patients with schizophrenia.
  
  
  
  This was a single-centre, randomized, double-blind, placebo-controlled trial performed from 27 August 2014 to 10 February 2016 (clinicaltrials.gov identifier: NCT02176044). Twenty patients with schizophrenia aged 18-60 years with a diagnosis of schizophrenia or schizoaffective disorder were recruited from psychiatric outpatient clinics in the South London and Maudsley NHS Trust, London, UK. Baseline symptoms were measured using the Positive and Negative Syndrome Scale (PANSS) and the 18-item Brief Psychiatric Rating Scale (BPRS-18), and SWM was assessed using the CANTAB computerized test. Participants received either an infusion of SNP (0.5 μg/kg per min for 4 h) or placebo and were re-assessed for symptoms and SWM performance immediately after the infusion, and 4 weeks later.
  
  
  
  SNP did not lead to any reduction in psychotic symptoms or improvement in SWM performance compared to placebo.
  
  
  
  Although this study was negative, it is possible that the beneficial effects of SNP may occur in patients with a shorter history of illness, or with more acute exacerbation of symptoms.
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: J M
authors.initials: JM
authors.lastname: Stone
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: P D
authors.initials: PD
authors.lastname: Morrison
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: I
authors.initials: I
authors.lastname: Koychev
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: F
authors.initials: F
authors.lastname: Gao
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: T J
authors.initials: TJ
authors.lastname: Reilly
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: M
authors.initials: M
authors.lastname: Kolanko
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: A
authors.initials: A
authors.lastname: Mohammadinasab
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: S
authors.initials: S
authors.lastname: Kapur
authors.affiliation: King's College London, Institute of Psychiatry Psychology and Neuroscience,London,UK.
authors.forename: P K
authors.initials: PK
authors.lastname: McGuire
mesh_terms: D000328:Adult; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008570:Memory, Short-Term; D008875:Middle Aged; D009599:Nitroprusside / Q000627:therapeutic use*; D011618:Psychotic Disorders / Q000188:drug therapy* / Q000503:physiopathology / Q000523:psychology; D012559:Schizophrenia / Q000188:drug therapy* / Q000503:physiopathology; D012565:Schizophrenic Psychology; D065852:Spatial Memory; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D014665:Vasodilator Agents; D009599:Nitroprusside
keywords: Clinical trial; nitric oxide; schizophrenia; sodium nitroprusside; spatial working memory