What is it used for?
May help support a modest improvement in exercise capacity in individuals with stable cardiovascular diseases (CVD) [Source note 2].
L-Arginine is (a non-essential amino acid) involved in protein synthesis [Source note 3].
Who does this guide cover?
Adults 18 years and older
How is it taken?
Oral
Which forms are covered?
this reference excludes foods or food-like dosage forms as indicated in the Compendium of references Guidance Document.
.
Quantities
Improvement in exercise capacity in individuals with stable CVD
6 - 21 grams of L-Arginine, per day; Not to exceed 8 grams per single dose (Doutreleau et al. 2010; Shao and Hathcock 2008; Doutreleau et al. 2006; Evans et al. 2004: Lim et al. 2004; Palloshi et al. 2004; Bode-Bogër et al. 2003; Bednarz et al. 2000; Hambrecht et al. 2000; Lerman et al. 1998; Adams et al. 1997; Ceremużyński et al. 1997; Clarkson et al. 1996; Rector et al. 1996).
Protein synthesis
0.21 - 21 grams of L-Arginine, per day; Not to exceed 8 grams per single dose [Source note 4].
How is it used?
The reference does not require an additional label statement in this section. This does not establish an absence of risk.
How long is it used?
Products providing 3 g or more of L-Arginine, per day
Ask a healthcare professional for use beyond 8 weeks if you have a cardiovascular disease (Salmani et al. 2021; Sydow et al. 2002; Hambrecht et al. 2000; Clarkson et al.1996; Rector et al. 1996).
Products providing more than 9 g and up to 14 g of L-Arginine, per day
Ask a healthcare professional for use beyond 6 months [Source note 5].
Products providing more than 14 g of L-Arginine, per day
Ask a healthcare professional for use beyond 12 weeks [Source note 6].
Note: Durations of use can be combined on the label (e.g., Ask a health care practitioner for use beyond 6 months, or beyond 8 weeks if you have a cardiovascular disease).
Warnings and precautions
All products
Ask a healthcare professional/ physician before use if you are pregnant or breastfeeding.
Improvement in exercise capacity in individuals with stable CVD
Ask a healthcare professional/ physician if your symptoms worsen.
Products providing more than 0.42 g of L-Arginine, per day
Ask a healthcare professional/ physician before use if you have a cardiovascular disease and are attempting an increase in physical activity [Source note 7].
Ask a healthcare professional/ physician before use if you are taking medication for cardiovascular diseases, erectile dysfunction, and/or blood thinners [Source note 8].
When should it be avoided?
Products providing more than 9 g of L-Arginine, per day
Do not use if you have had a heart attack/myocardial infarction [Source note 9].
Possible side effects
Products providing more than 9 g of L-Arginine, per day
When using this product you may experience gastrointestinal discomfort/disturbances [Source note 10].
Storage
Must be established in accordance with the requirements described in the applicable product regulations.
Preparation details
Ingredient identity, preparation requirements, and other details that define the scope of this guide.
Ingredients and preparations
| Proper name(s) | Common name(s) | Source Information / Source ingredient(s) | Source Information / Preparation(s) |
|---|---|---|---|
| L-Arginine |
| Synthetic |
References: Proper names: NIH 2023; RSC 2023; Common name: NIH 2023; RSC 2023; Source information: NIH 2023; USP-NF 2023; BP 2009; Ph. Eur. 2007.
Other ingredients
Must be chosen from the current source ingredient database and must meet the limitations outlined in the database.
Preparation and quality requirements
The finished product specifications must be established in accordance with the requirements described in the source authority source’s product quality guidance.
The active ingredient must comply with the requirements outlined in the source ingredient database.
Guide change history
Updates to this SupplementSafety.org guide.
Minor updates
Updated guide wording, organization, and source presentation. Added our editorial change history.
Initial release
Initial SupplementSafety.org guide prepared from source reference material.
Validation: Not yet completed. Editorial updates do not constitute clinical validation.
Sources
Source information
This guide organizes source material about uses, preparations, amounts, and precautions. Read the conditions alongside each statement; the information may apply only to particular preparations or populations.
The source document includes supporting references. We have not independently summarized or assessed every cited study for this guide.
- Source document version
- July 25, 2025
- Source captured
- Aug 15, 2026
- Editorial work
- Editorial preparation. Independent clinical review has not been recorded for this guide.
Full citations are available through the link above. Verification is required to open them; reading this guide does not require verification.
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Explore our supplement–medication interaction checker. Its coverage and review status are shown with the results; a missing finding does not establish that a combination is safe.