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L-arginine add-on Therapy in Patients With Schizophrenia

Not Applicable
Completed
Conditions
Schizoaffective Disorder
Schizophrenia
Interventions
Dietary Supplement: L-Arginine
Other: Placebo
Registration Number
NCT02398279
Lead Sponsor
Hacettepe University
Brief Summary

This study evaluates the addition of L-Arginine to the usual regimen in the treatment of schizophrenia in adults. As a requisite of crossover design, half of the participants started with L-Arginine and the other half with placebo and switched over after a three weeks use and one week of a washout period.

Detailed Description

L-arginine is the precursor of nitric oxide (NO), a neuromodulator of dopamine, gamma-aminobutyrate (GABA) and glutamate systems. Nitric oxide donors which increase NO levels at the cellular level could improve N-methyl-D-aspartate (NMDA) receptor dysfunction. Using L-arginine could bypass the blocked NMDA receptors and improve the therapeutic efficacy by reversing the dysfunction.

The investigators proposed that using L-Arginine, a dietary supplement in most cultures, might constitute a safe option as an add-on treatment which may display beneficial effects on positive, negative, cognitive and affective symptoms associated with schizophrenia.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
12
Inclusion Criteria
  • Schizophrenia-Schizoaffective Disorder
  • Clinical Global Impression >4
  • Able to take oral medication and likely to comply the required evaluations
  • On stable medication regimen for 8 weeks
  • Competent and willing to give informed consent
Exclusion Criteria
  • Uncontrolled medical illness (renal disease, hepatic, cardiac diseases, gout, asthma, diabetes, sickle cell anemia, low-high blood pressure)
  • History of Myocardial Infarction (MI)
  • History of genital herpes infections/ receiving lysine containing treatments
  • Pregnancy/ lactation
  • Substance related and Addictive Disorders
  • Drugs that might induce hypotension
  • Intolerance to L-arginine and ingredients of placebo or L-arginine capsule

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
L-Arginine-FirstL-ArginineFor the first three weeks, L-Arginine 3 g bid (500mg capsules 6 x 2), one week wash-out, then for the next three weeks placebo capsules (6 x 2)
L-Arginine-FirstPlaceboFor the first three weeks, L-Arginine 3 g bid (500mg capsules 6 x 2), one week wash-out, then for the next three weeks placebo capsules (6 x 2)
Placebo-FirstL-ArginineFor the first three weeks, placebo capsules (6 x 2), one week wash-out, then for the next three weeks L-Arginine 3 g bid (500 mg capsules 6 x 2)
Placebo-FirstPlaceboFor the first three weeks, placebo capsules (6 x 2), one week wash-out, then for the next three weeks L-Arginine 3 g bid (500 mg capsules 6 x 2)
Primary Outcome Measures
NameTimeMethod
Change from baseline in Positive and Negative Syndrome Scalebaseline and week 3

Evaluating change in Positive and Negative Syndrome Scale between baseline and Week 3, comparing subjects treated with L-Arginine for 3 weeks to subjects treated with placebo for 3 weeks.

Secondary Outcome Measures
NameTimeMethod
Change from baseline in Neuropsychological Test Batterybaseline and week 3

Evaluating change in Neuropsychological Test Battery between baseline and Week 3, comparing subjects treated with L-Arginine for 3 weeks to subjects treated with placebo for 3 weeks.

Change from baseline in the The Calgary Depression Scale for Schizophreniabaseline and week 3

Evaluating change in The Calgary Depression Scale for Schizophrenia between baseline and Week 3, comparing subjects treated with L-Arginine for 3 weeks to subjects treated with placebo for 3 weeks.

Change from baseline in Clinical Global Impression - Severitybaseline and week 3

Evaluating change in Clinical Global Impression - Severity between baseline and Week 3, comparing subjects treated with L-Arginine for 3 weeks to subjects treated with placebo for 3 weeks.

Change from baseline in Abnormal Involuntary Movement Scalebaseline and week 3

Evaluating change in Abnormal Involuntary Movement Scale between baseline and Week 3, comparing subjects treated with L-Arginine for 3 weeks to subjects treated with placebo for 3 weeks.

Change from baseline in Uku Side Effects Rating Scalebaseline and week 3

Evaluating change in Uku Side Effects Rating Scale between baseline and Week 3, comparing subjects treated with L-Arginine for 3 weeks to subjects treated with placebo for 3 weeks.

Change from baseline in blood pressurebaseline and week 7
Change from baseline in respiratory ratebaseline and week 7
Change from baseline in heart ratebaseline and week 7
Change from baseline in temperaturebaseline and week 7
Change from baseline in electrocardiogrambaseline and week 7
Change from baseline in weightbaseline and week 7
Change from baseline in complete blood countbaseline and week 7

Composed of different measures. Change in any measure indicates impairment in the composite measure

Change from baseline in alanine aminotransferasebaseline and week 7
Change from baseline in aspartate aminotransferasebaseline and week 7
Change from baseline in ureabaseline and week 7
Change from baseline in alkaline phosphatasebaseline and week 7
Change from baseline in creatininebaseline and week 7
Change from baseline in sodiumbaseline and week 7
Change from baseline in calciumbaseline and week 7
Change from baseline in total cholesterolbaseline and week 7
Change from baseline in potassiumbaseline and week 7
Change from baseline in chloridebaseline and week 7
Change from baseline in thyroid-stimulating hormonebaseline and week 7
Change from baseline in free T4baseline and week 7
Change from baseline in HDLbaseline and week 7
Change from baseline in LDLbaseline and week 7
Change from baseline in triglyceridesbaseline and week 7
Change from baseline in human chorionic gonadotropinbaseline and week 7

Pregnancy test in women

Trial Locations

Locations (1)

Hacettepe University Faculty of Medicine Department of Psychiatry

🇹🇷

Ankara, Turkey

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