Evaluation of the Effect of L-Arginine on the Cognitive Function in Geriatric Patients

Evaluation of the Effect of L-Arginine on the Cognitive Function in Geriatric Patients, A Randomized Clinical Trial

This study aims to evaluate the effect of L-arginine supplementation on cognitive function in geriatric patients. Eligible participants will receive either L-arginine (6 grams once daily) or placebo, and their cognitive performance will be assessed using validated cognitive assessment tools over the study period. The participants will receive the intervention for 4 weeks and followed up every 2 weeks. The primary outcome is improvement in cognitive function, while secondary outcomes include safety, tolerability, and quality of life measures. The findings may provide evidence for the potential role of L-arginine in supporting cognitive health in elderly populations.

Study Overview

• Status: Recruiting
• Conditions: Cognition Disorders in Old Age; Cognitive and Behavioral Impairment
• Intervention / Treatment: Dietary supplement: L-Arginine; Other: Placebo

Detailed Description

Cognitive decline is a common problem in the geriatric population and can significantly affect independence, quality of life, and overall health outcomes. Emerging evidence suggests that L-arginine, a semi-essential amino acid and precursor for nitric oxide synthesis, may play a role in improving cerebral blood flow and neuronal function. These mechanisms could potentially contribute to better cognitive performance in elderly individuals.

This study is designed to evaluate the effect of L-arginine supplementation on cognitive function in geriatric patients. Participants who meet eligibility criteria will be randomized to receive either L-arginine supplementation or placebo. Cognitive function will be assessed at baseline and at defined intervals during the study period using validated neurocognitive assessment tools. Additional measures will include safety monitoring, tolerability, and secondary assessments such as quality of life indices.

The primary objective is to determine whether L-arginine supplementation improves cognitive function. Secondary objectives include evaluating the anti-inflammatory, antioxidant effect and safety profile of L-arginine in older adults and assessing its potential impact on daily living and overall well-being. The results of this study may provide valuable insights into the role of L-arginine in supporting cognitive health in elderly populations and inform future clinical practice.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Phase 2

Contacts and Locations

Study Locations

• Egypt
  • Cairo, Egypt
    • Recruiting
    • Neurology Department, Al-Azhar University Hospitals
    • Contact: Rama Elmor; Phone Number: +201013899711; Email: rama.mohamed@guc.edu.eg

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age >60 years
• Montreal Cognitive Assessment (MoCA) test score from 10-25 (mild to moderate cognitive impairment)

Exclusion Criteria:

• Presence of neurodegenerative diseases (e.g.: Alzheimer's disease, Parkinson's disease, Huntington's disease, Multiple Sclerosis)
• Patients with history of L-arginine intolerance or allergy
• Patients with asthma
• Patients who recently had an acute myocardial infarction
• Patients with history of stroke within 1 yaear
• Patients who started or discontinued medications that may affect cognitive function (e.g., CNS psychotropics, antihistamines, or acetylcholinesterase inhibitors) during the study period.
• Patients who initiated or stopped antihypertensive medications during the study period.
• Patients who initiated or stopped antidiabetic medications during the study period.
• Patients who initiated or stopped antihyperlipidemic medications during the study period.
• Patients prescribed medications for depression, anxiety, or stress that may impact cognitive function
• Patients on nitrates, phosphodiesterase-5 inhibitors, potassium sparing diuretics
• Refusal to provide written informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Placebo; Matching placebo once daily	Other: Placebo; Matching Placebo of L-arginine
Experimental: L-Arginine; 6 grams sachets of L-arginine once daily	Dietary supplement: L-Arginine; 6 grams L-arginine sachets taken orally once daily

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Montreal Cognitive Assessment (MOCA)	MOCA is a is a brief cognitive screening tool used to detect mild cognitive impairment (MCI) and early dementia. It assesses multiple cognitive domains including memory, attention, executive function, language, visuospatial skills, abstraction, calculation, and orientation. The score ranges from 0- 30. The higher the score the better the cognition. The normal range is from 26-30.	at baseline, after 2 weeks, and after 4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ADMA	Asymmetric dimethylarginine	at baseline and after 4 weeks
MDA	Malondialdehyde	at baseline and after 4 weeks
CRP	C-reactive protein	at baseline and after 4 weeks
Lipid Profile		at baseline and after 4 weeks
Kidney Function test	Serum Creatinine	at baseline and after 4 weeks
Liver Function Tests	ALT and AST	at baseline and after 4 weeks
Depression, Anxiety, Stress Scales-21 (DASS-21)	DASS-21 is a short self-report questionnaire used to assess depression, anxiety, and stress over the past week. It consists of 21 items, with 7 items for each subscale, rated on a 4-point Likert scale. Each subscale has a raw score range of 0-21and the higher the score the worse the outcome of symptoms of depression, anxiety, or stress.	at baseline, after 2 weeks, and after 4 weeks
The World Health Organization Quality of Life (WHOQOL-BREF)	WHOQOL-BREF is a brief, self-administered questionnaire that assesses an individual's perceived quality of life. It consists of 26 items covering four domains: physical health, psychological health, social relationships, and environment. Score can range from 0-100 for each domain with higher scores meaning a better quality of life.	at baseline, after 2 weeks, and after 4 weeks

Collaborators and Investigators

• Sponsor: German University in Cairo

Study record dates

Study Major Dates

• Study Start (Actual): August 27, 2025
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 30, 2026

Study Registration Dates

• First Submitted: January 4, 2026
• First Submitted That Met QC Criteria: January 4, 2026
• First Posted (Actual): January 14, 2026

Study Record Updates

• Last Update Posted (Actual): January 21, 2026
• Last Update Submitted That Met QC Criteria: January 18, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Elderly; Cognitive impairment; Geriatrics; Cognitive Function; L-arginine; Nitric Oxide
• Additional Relevant MeSH Terms: Mental Disorders; Neurocognitive Disorders; Cognition Disorders; Cognitive Dysfunction; Amino Acids, Peptides, and Proteins; Amino Acids; Amino Acids, Basic; Amino Acids, Diamino; Amino Acids, Essential; Arginine
• Other Study ID Numbers: L-Arg_on_MCI_in_Geriatrics

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No