Some men use L-arginine for erectile dysfunction (ED) and to improve libido and sexual performance.
According to the Mayo Clinic, ED is characterised by the inability of the man to get or keep an erection for sex.
L-arginine is an amino acid and a precursor to nitric oxide. Nitric oxide is a signalling molecule that plays many roles in the human body, one of which is the relaxation of smooth muscle during an erection.
L-arginine supplements are sometimes used for ED because of its involvement in nitric oxide synthesis.
An erection is the result of a series of physiological steps, beginning with sexual stimulation, which causes the brain to send nerve impulses that relax the smooth muscles and arteries that supply blood to the penis. This relaxation allows blood to engorge the penis, causing it to become erect.
An interruption at any step of the process can impair a man’s ability to get an erection.
There are many causes of ED, including: hypertension (high blood pressure), decreased blood flow, old age, diabetes mellitus, hormone problems, depression or other psychological difficulties, smoking, excessive alcohol consumption, drug abuse, pelvic surgery and disorders of the nervous system.



- Boosts nitric oxide production for workouts
- Reduces fatigue & promotes muscle growth
- Supports immune function & sexual health
L-Arginine for ED and Men’s Health
Related Topics
- L-Arginine
- L-Arginine Benefits
- Benefits for Men
- Benefits for Bodybuilding
- Effects on Blood Pressure
- Arginine Aspartate
- Arginine Alpha-Ketoglutarate
- Arginine Pyroglutamate
- Arginine Ornithine and Lysine
- Suggested Dosages
- Food Sources
- Comparison to L-Citrulline
- Best Supplement
- Topical Cream
- 500 mg Tablets
- Arginine Extreme
- Buy L-Arginine Powder
- Side Effects
L-arginine is characterised as a semi-essential amino acid.
This means that the body normally produces enough L-arginine, but sometimes supplementation is required.
For example, supplementation is sometimes necessary for individuals with protein malnutrition, excessive lysine consumption and high ammonia levels.
In general, L-arginine is involved in protein synthesis and is also a precursor to nitric oxide. L-arginine is a substrate for the enzyme known as endothelial nitric oxide synthase (eNOS), which acts on L-arginine to produce nitric oxide.
Nitric oxide is a signalling molecule involved in a number of physiological functions, including the development of erections. It relaxes smooth muscle and blood vessels, which is necessary to allow sufficient blood flow to the penis for an erection.
L-arginine levels can be increased by eating a diet rich in the amino acid. Examples of L-arginine-rich foods include green leafy vegetables, certain seafood, lean meats and cheeses.
L-arginine supplements are available in the form of capsules, liquids, powders, strips and tablets.
For the treatment of ED and for generally improving sex drive and fertility, L-Arginine is often combined with other supplements. It is often used with Pycnogenol (Pine Bark Extract), L-Citrulline, Horny Goat Weed, Tongkat Ali and Korean Ginseng.
Understanding Erectile Dysfunction
ED is sometimes associated with male infertility, but the two are separate conditions. ED refers to the inability to get and sustain an erection.
Male infertility refers to the difficulty or inability to conceive a child. This may encapsulate a host of other physiological issues, including sperm quantity, sperm motility and ability to achieve organism.
In a healthy male, an erection results when sexual stimulation is experienced – either mentally or physically. This stimulation triggers a series of physiological events that allow blood to flow to the penis and stay there until ejaculation.
An important part of this process is the relaxation of smooth muscle, which allows for the expansion of the penis and the containment of blood in the penis.
The penis contains three cylinder-shaped tubes of tissue. These tubes are referred to the corpus spongiosum and a pair of corpora cavernosa (individually known as the corpus cavernosum – CC). Blood is supplied to these tissues by the helicine arteries.
For an erection to take place, the smooth muscle within both the arteries and the CC must relax to allow for more blood flow. As the penis fills with blood and expands, veins are constricted and blood is kept in the penis. A defect in this relaxation pathway is associated with ED.
Nitric oxide triggers the accumulation of the molecule cGMP, which stands for cyclic guanosine monophosphate. Researchers note that cGMP is a main mediator allowing for the relaxation of the CC and surrounding muscle. This pathway explains why the presence of nitric oxide plays an important role in achieving an erection.
Mechanisms of ED Medications and Treatments
Without an accumulation of cGMP relaxation of the smooth tissue does not occur and an erection is not generated.
Many available ED medications work by inhibiting an enzyme called PDE5 (phosphodiesterase type 5), which degrades cGMP and impedes the accumulation necessary to cause an erection.
The four available PDE5 inhibitors are sildenafil (Viagra), tadalafil (Cialis), vardenafil (Levitra) and avanafil (Stendra).
Some opt to take L-arginine as a means of increasing nitric oxide production and cGMP concentration. Natural Medicines rates a high dose of oral L-arginine (5 g per day) as Possibly Effective for erectile dysfunction.
In a 1999 study, men with organic ED reported subjective improvements in erectile function while taking 5 g of L-arginine. [1] The same effect has not been observed at lower doses. [2]
L-arginine is sometimes combined with French Maritime pine bark extract (pycnogenol) for the symptoms of ED. This supplement also increases nitric oxide activity and acts as a vasodilator to support erectile function.
Other treatment options for ED include (but are not limited to) penile implants, prostaglandin tablets, penile injections, penis pumps and/or reconstructive vascular surgery.
L-Arginine: Safety for ED Symptoms
Natural Medicines rates the use of L-arginine as “Possibly Safe” when used short term at appropriate doses. [2] There is insufficient data to determine the safety of long-term use.
Follow the label instructions when taking L-arginine. Do not use L-arginine for ED if you are taking a PDE5 inhibitor like Viagra.
Speak with your doctor before taking L-arginine for ED. This is particularly important if you suffer from herpes, low blood pressure or any cardiovascular disorder.
- Chen J, Wollman Y, Chernichovsky T, Iaina A, Sofer M, Matzkin H.Effect of oral administration of high-dose nitric oxide donor L-arginine in men with organic erectile dysfunction: results of a double-blind, randomized, placebo-controlled study. BJU Int. 1999 Feb;83(3):269-73.
- Natural Medicines. L-Arginine: Professional Monograph. Reviewed May 2013.
- Klotz T, Mathers MJ, Braun M, Bloch W, Engelmann U. Effectiveness of oral L-arginine in first-line treatment of erectile dysfunction in a controlled crossover study. Urol Int. 1999;63(4):220-3.
- Lacchini R, Muniz JJ, Nobre YT, Cologna AJ, Martins AC, Tanus-Santos JE. Relationship between Arginase 1 and Arginase 2 levels and genetic polymorphisms with erectile dysfunction. Nitric Oxide. 2015 Oct 29. pii: S1089-8603(15)30025-2.
- Stanislavov R, Nikolova V. Treatment of erectile dysfunction with pycnogenol and L-arginine. J Sex Marital Ther. 2003 May-Jun;29(3):207-13.
- Kobori Y, Suzuki K, Iwahata T, Shin T, Sadaoka Y, Sato R, Nishio K, Yagi H, Arai G, Soh S, Okada H, Strong JM,Rohdewald P. Improvement of seminal quality and sexual function of men with oligoasthenoteratozoospermia syndrome following supplementation with L-arginine and Pycnogenol®. Arch Ital Urol Androl. 2015 Sep 30;87(3):190-3.
- Lai X, Kline JA, Wang M. Development, validation, and comparison of four methods to simultaneously quantify l-arginine, citrulline, and ornithine in human plasma using hydrophilic interaction liquid chromatography and electrospray tandem mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci. 2015 Oct 17;1005:47-55.
- Kalman DS, Feldman S, Samson A, Krieger DR.A clinical evaluation to determine the safety, pharmacokinetics, and pharmacodynamics of an inositol-stabilized arginine silicate dietary supplement in healthy adult males. Clin Pharmacol. 2015 Oct 7;7:103-9.
- Bersani FS, Wolkowitz OM, Lindqvist D, Yehuda R, Flory J, Bierer LM, Makotine I, Abu-Amara D, Coy M, Reus VI, Epel ES, Marmar C, Mellon SH. Global arginine bioavailability, a marker of nitric oxide synthetic capacity, is decreased in PTSD and correlated with symptom severity and markers of inflammation. Brain Behav Immun. 2015 Oct 26.
- Toni M, De Angelis F, di Patti MC, Cioni C. Nitric Oxide Synthase in the Central Nervous System and Peripheral Organs of Stramonita haemastoma: Protein Distribution and Gene Expression in Response to Thermal Stress. Mar Drugs. 2015 Oct 30;13(11):6636-64.
- DiSanto ME. Pathways to relaxation of corporal smooth muscle. Curr Sex Health Rep. 2006 Sept;3(3): 113-119.
Article last updated on: March 18th, 2018 by Nootriment