- What is L-arginine? L-arginine (or arginine) is an amino acid which is necessary for the body's production of nitric oxide, a compound that relaxes blood vessels and allows more blood to flow through arteries. The form in supplements is typically "free form" arginine, but is sometimes a compound, such as L-arginine HCl. (See What It Is). Not all labels clearly list the amount of arginine. (See What to Consider When Buying), but you can use the Results table to easily compare amounts of arginine in tested supplements.
- What are the health benefits of L-arginine? L-arginine may modestly improve symptoms, such as exercise intolerance, in congestive heart failure, angina, and leg pain due to intermittent claudication, as well as exercise endurance in recreational and older athletes. Some, but not all, studies have shown some modest benefits in sexual dysfunction and Raynaud's syndrome (See What It Does).
- How much L-arginine to take? Dosage depends on the condition being treated, but is typically several thousand milligrams per day (See Dosage).
- Best L-arginine products? Among the products that passed our laboratory tests (See What CL Found), we selected Top Picks for arginine for general use, cardiovascular, sexual enhancement, and sport.
- L-arginine safety and side effects: L-arginine supplementation appears to be generally safe and well tolerated in healthy individuals, although stomach upset may occur and capsules have been reported to irritate the esophagus — so be sure to take with water. L-arginine may interact with blood-pressure lowering and diabetes medications. Do not use if you have had a heart attack, and do not use to treat serious conditions including congestive heart failure, angina, or intermittent claudication without physician supervision. For details, see Concerns and Cautions.
L-Arginine Supplements Review
Choose the Best L-Arginine Supplement . Find Out Which L-Arginine Supplement Passed CL's Tests

Alphabetical list of L-arginine supplement brands compared in this review

Country Life L-Arginine Caps

Daily Wellness ArginMax- Women

Elements of Health Care L-Arginine Plus - Grape

GNC L-Arginine

Havasu Nutrition L-Arginine Extra Strength

MuscleTech L-Arginine SX-7 Black Onyx

NOW L- Arginine

PipingRock.com L-Arginine

Purethentic Naturals Premium Arginine
Puritan's Pride L-Arginine

Rexall [Dollar General] L- Arginine

Solgar L-Arginine 500 mg

Spring Valley [Walmart] L- Arginine

Sundown Naturals L-Arginine 500 mg

Swanson Super Strength L-Arginine

The Vitamin Shoppe L-Arginine

Twinlab L-Arginine

Vitacost L- Arginine HCl

Vitamin World Maximum Strength L-Arginine
Make sure the L-arginine supplement you take passed our test and is right for you!
Isn't your health worth it?
See the Review Now
Already a member? Sign in here.
Join now at www.consumerlab.com/join/
Summary
You'll get the following information about L-arginine supplements in this comprehensive review:
- Which L-arginine supplements passed or failed testing
- Which L-arginine supplements are the best value and CL's Top Picks
- What L-arginine can and cannot do for your health
- How forms of L-arginine ("free form," L-arginine HCl, and L-arginine-alpha-ketoglutarate) differ from one another
- The dose of L-arginine for specific uses
- What to look for on product labels and how to take L-arginine supplements
- Why the amino acid citrulline is often added to L-arginine supplements and whether it's been shown to help
- Cautions, side effects, and drug interactions with L-arginine
Join to unlock the full report and get full access to over 1,300 reviews
See the Review NowAlready a member? Sign in here.
Join now at www.consumerlab.com/join/
As a ConsumerLab.com member, you may print a copy of this report for your personal use.
You can access a special print version by clicking the "Print" icon in the upper right corner of this report. You can then use your web browser's print functions to print the whole report or just selected pages.
You may also email or post a link to this report using the web address above. Non-members using the link will see a free summary and can join to view the full report. Other means of copying or distributing this report, in part or full, are not permitted.
If you are sight-impaired and your computer is having trouble converting the text in this report to speech, contact us for assistance at Membership@ConsumerLab.com or by phone at 914-722-9149.