Repository of Research and Investigative Information

Repository of Research and Investigative Information

Kurdistan University of Medical Sciences

L-lysine as an adjunct to risperidone in patients with chronic schizophrenia: A double-blind, placebo-controlled, randomized trial

(2014) L-lysine as an adjunct to risperidone in patients with chronic schizophrenia: A double-blind, placebo-controlled, randomized trial. Journal of Psychiatric Research.

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Increasing evidence suggest that the nitric oxide signaling system of the brain may contribute to the pathophysiology of schizophrenia, making this system a target for development of novel therapeutics. The objective of this study was to investigate the efficacy and safety of l-lysine as an adjunctive to risperidone in the treatment of patients with chronic schizophrenia during an 8-week trial. Seventy-two chronic schizophrenia inpatients with a Positive and Negative Syndrome Scale (PANSS) total score of ≥60 participated in a randomized, double-blind, placebo-controlled trial in the active phase of their disease and underwent 8 weeks of treatment with either l-lysine (6g/day) or placebo as an adjunctive to risperidone. Patients were evaluated using PANSS and its subscales at baseline and weeks 2, 4, 6 and 8. The primary outcome measure was to evaluate the efficacy of l-lysine in improving schizophrenia symptoms. Repeated measures analysis demonstrated significant effect for time×treatment interaction on the PANSS total (P<0.001), negative (P<0.001) and general psychopathology (P<0.001) subscale scores but not the PANSS positive subscale scores (P=0.61). The frequency of adverse events (AEs) did not differ significantly between the two treatment groups and no serious AE was observed. The present study demonstrated that l-lysine can be a tolerable and efficacious adjunctive therapy for improving negative and general psychopathology symptoms in chronic schizophrenia. However, the safety and efficacy of higher doses of l-lysine and longer treatment periods still remain unknown. © 2014 Elsevier Ltd. All rights reserved.

Item Type: Article
Keywords: lysine; placebo; risperidone; lysine; neuroleptic agent; risperidone, abdominal pain; adult; Article; comparative study; controlled study; diarrhea; dizziness; double blind procedure; drug efficacy; drug safety; Extrapyramidal Symptom Rating Scale; female; follow up; Hamilton scale; headache; human; major clinical study; male; mental patient; named inventories, questionnaires and rating scales; nausea; negative syndrome; Positive and Negative Syndrome Scale; randomized controlled trial; rash; schizophrenia; vomiting; xerostomia; chronic disease; complication; depression; psychological rating scale; schizophrenia; treatment outcome; young adult, Adult; Antipsychotic Agents; Chronic Disease; Depression; Double-Blind Method; Female; Follow-Up Studies; Humans; Lysine; Male; Psychiatric Status Rating Scales; Risperidone; Schizophrenia; Treatment Outcome; Young Adult
Page Range: pp. 125-131
Journal or Publication Title: Journal of Psychiatric Research
Volume: 59
Identification Number: 10.1016/j.jpsychires.2014.08.016
Depositing User: مهندس جمال محمودپور

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