Arginine

Also known as: L-arginine, arginine sodium succinate, L-arginine HCl

Evidence under review. — Not yet rated

Amino acid with some evidence for blood flow support; most oral supplement claims lack strong clinical backing.

What it does

Arginine is an amino acid the body uses to produce nitric oxide, a molecule that helps relax and widen blood vessels. One clinical trial found intravenous arginine sodium succinate improved...
Evidence quality

Evidence base hasn't been formally rated yet. See research below.
Clinical dose

No established dose from provided studies
Found in

1.M.R OG Pre-Workout Formula, Augustinus Bader The Hair Revitalizing Complex, BEYOND RAW (Brand) and 14 more

What the Science Says

Arginine is an amino acid the body uses to produce nitric oxide, a molecule that helps relax and widen blood vessels. One clinical trial found intravenous arginine sodium succinate improved walking distance in patients with peripheral artery disease better than a standard drug. Lab research also suggests arginine plays a role in immune cell function, particularly in helping macrophages fight infection.

What It Doesn't Do

No evidence from these studies that oral arginine supplements boost athletic performance or build muscle. No proof it meaningfully raises nitric oxide levels in healthy people at typical supplement doses. Don't expect it to cure circulation problems on its own. The skin-aging study used arginine as a delivery vehicle, not as the active ingredient.

Evidence-Based Benefits

Intravenous arginine sodium succinate improved walking distance in peripheral artery disease patients better than pentoxifylline.

Moderate Evidence

Effective at: 12-day IV infusion course (dose not specified in abstract)

Supporting studies (click to view on PubMed):

PMID 41805668

Arginine availability helps macrophages produce nitric oxide, supporting the immune system's ability to fight infection.

Weak Evidence

Effective at: No established dose from provided studies

Supporting studies (click to view on PubMed):

PMID 42164505

Absorption & Bioavailability

Unknown from provided studies — the clinical vascular trial used intravenous infusion, not oral supplementation. Oral bioavailability data not covered in the provided papers.

Red Flags to Watch For

Most clinical evidence in these papers used intravenous arginine, not oral supplements — results may not translate to pills or powders
At high concentrations (1 mM), arginine caused measurable DNA damage in lab studies of urea cycle disorders — context matters but warrants caution at very high doses
Arginine is used in LysaKare infusions for cancer patients and can affect potassium levels — people with kidney disease or on medications should consult a doctor
Many products use arginine as a filler or delivery agent rather than as the primary active ingredient

Supplement

Mostly Legit

Everyday Dose

Supplement

Mostly Legit

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Frequently Asked Questions

What does Arginine do?

Amino acid with some evidence for blood flow support; most oral supplement claims lack strong clinical backing.

What is the effective dose of Arginine?

No established dose from provided studies

Is Arginine safe?

Most clinical evidence in these papers used intravenous arginine, not oral supplements — results may not translate to pills or powders

What doesn't Arginine do?

No evidence from these studies that oral arginine supplements boost athletic performance or build muscle.

Research Sources

PubMed
NIH DSLD

This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-05-25