Quick Search
CAS number: 74-79-3
EC number: 230-571-3
Chemical Formula: C6H14N4O2
Molar Mass: 174.204 g·mol−1
L-arginine is an amino acid naturally found in red meat, poultry, fish, and dairy.
L-arginine is necessary for making proteins and is commonly used for circulation.
L-arginine is converted in the body into a chemical called nitric oxide.
Nitric oxide causes blood vessels to open wider for improved blood flow.
L-arginine also stimulates the release of growth hormone, insulin, and other substances in the body.
L-arginine can be made in a lab and used in supplements.
People use L-arginine for chest pain and various blow flow issues, erectile dysfunction, high blood pressure during pregnancy, and a serious disease in premature infants called necrotizing enterocolitis (NEC).
L-arginine's also used for many other conditions, but there is no good scientific evidence to support these other uses.
L-arginine is an amino acid that helps the body make proteins.
L-arginine can be obtained naturally in the diet and is also found in dietary supplement form.
Foods rich in L-arginine include plant and animal proteins, such as dairy products, meat, poultry, fish, and nuts.
In addition to building protein, L-arginine releases nitric oxide in the blood.
Nitric oxide acts to widen blood vessels in the blood stream, which may help aid certain circulatory conditions.
A person’s body naturally produces L-arginine under normal circumstances.
People also get additional L-arginine as part of their regular diet.
Red meats, fish, dairy, and eggs all contain low amounts of L-arginine that help the body to replenish L-arginines necessary resources.
Arginine, also known as l-arginine (symbol Arg or R), is an α-amino acid that is used in the biosynthesis of proteins.
L-arginine contains an α-amino group, an α-carboxylic acid group, and a side chain consisting of a 3-carbon aliphatic straight chain ending in a guanidino group.
At physiological pH, the carboxylic acid is deprotonated (−COO−), the amino group is protonated (−NH3+), and the guanidino group is also protonated to give the guanidinium form (-C-(NH2)2+), making arginine a charged, aliphatic amino acid.
L-arginine is the precursor for the biosynthesis of nitric oxide.
L-arginine is encoded by the codons CGU, CGC, CGA, CGG, AGA, and AGG.
Arginine is classified as a semiessential or conditionally essential amino acid, depending on the developmental stage and health status of the individual.
Preterm infants are unable to synthesize or create arginine internally, making the amino acid nutritionally essential for them.
Most healthy people do not need to supplement with arginine because L-arginine is a component of all protein-containing foods and can be synthesized in the body from glutamine via citrulline.
Occasionally, a person’s need for L-arginine may exceed the body’s ability to produce or consume L-arginine naturally.
This is often true for older adults or people with certain medical conditions.
In these cases, people may be prescribed artificial L-arginine in the form of oral medication, injections, or creams.
Several potential health conditions may benefit from an increased intake of L-arginine.
L-arginine is an amino acid.
Amino acids are the building blocks of proteins and divided into essential and nonessential categories.
Nonessential amino acids are made in the body, but essential amino acids are not.
As such, they must be provided through dietary intake.
L-arginine is considered semi-essential or conditionally essential, meaning that L-arginine becomes essential under certain circumstances and conditions, including pregnancy, infancy, critical illness, and trauma.
L-arginine’s necessary for the production of nitric oxide, a signaling molecule that’s needed for a variety of bodily processes and functions, including blood flow regulation, mitochondrial function, and cellular communication.
Additionally, L-arginine acts as a precursor to other amino acids, including glutamate, proline, and creatine, and is essential for the health and functioning of your immune system.
Arginine is necessary for the development of T-cells, which are white blood cells that play central roles in immune response.
Because L-arginine has so many critical roles in your body, a deficiency in this amino acid can disrupt cellular and organ function and lead to serious adverse health outcomes.
L-arginine is produced in several ways.
L-arginine can be synthesized from the amino acid citrulline through the breakdown of body proteins, or L-arginine can be obtained through dietary protein intake.
L-arginine’s concentrated in certain protein-rich foods, including meat, poultry, dairy, nuts, soy products, and fish.
The average daily intake of L-arginine from foods is reported to be 4–6 grams.
For reference, research shows that a typical Western diet provides between 25–30% of total arginine present in the body.
Additionally, L-arginine can be obtained by taking supplements.
L-arginine supplements are widely available and can be found in powder, liquid, capsule, and tablet form at grocery stores, supplement stores, and online.
This article mainly focuses on the benefits and uses of L-arginine supplements.
L-arginine is an amino acid that helps make proteins.
L-arginine also becomes the gas nitric oxide (NO) in the body.
NO is important for erectile function because L-arginine helps blood vessels relax, so more oxygen-rich blood can circulate through your arteries.
Healthy blood flow to the arteries of the penis is essential for normal erectile function.
L-Arginine is an amino acid critical to the production of nitric oxide (NO) in the body.
NO helps regulate and improve blood circulation.
L-Arginine cannot be made in the body, but must obtained through food or supplementation.
Kyowa Quality L-Arginine is an pure, allergen-free ingredient that has been manufactured to the highest quality standards.
Eggs, meats, milk, soy proteins, peanuts, and walnuts are all sources of arginine.
The physiologically active form, L-arginine, is obtained by breaking down proteins.
Arginine also may be synthesized in the laboratory.
Because L-arginine may be synthesized in the body, L-arginine is classified as a nonessential amino acid in adults.
However, in children and in people with certain conditions (eg, infection, trauma), L-arginine synthesis may become compromised and then may be considered semi-essential.
Natural ways to get enough L-arginine:
A major benefit of obtaining L-arginine through diet is that L-arginine is difficult to get too much.
Therefore, some of the side effects of consuming too much L-arginine can be avoided.
On the other hand, food consumption alone may not provide enough L-arginine to meet a person’s needs.
A person should discuss their options with their doctor prior to changing their diet.
The best natural source for L-arginine is food high in protein.
For some people, animal proteins, such as red meat (beef), chicken and turkey breast, pork loin, and dairy products, may be the primary source of L-arginine.
For people who do not eat meat, plant-based proteins that contain L-arginine include lentils, chickpeas, peanuts, pumpkin seeds, and soybeans.
People who find they have a deficient amount of L-arginine to meet their needs may want to modify their diet to include foods rich in protein.
A dietician or doctor may be able to make meal plan suggestions to boost natural intake of L-arginine prior to taking supplements.
Uses of L-arginine:
L-arginine supplements are taken by many populations, including athletes and those who have certain medical conditions like high blood pressure, for a variety of reasons.
They’re also used in the clinical setting to treat critically ill people or those with wounds.
Research has shown that L-arginine may offer a variety of potential benefits when used as a supplement.
However, results are mixed, and L-arginine may not be as effective for some conditions as many supplement companies claim.
Athletic performance enhancement:
Limited evidence suggests that L-arginine supplements may enhance exercise performance by increasing nitric oxide in the body, which improves blood flow and oxygenation to muscles.
For example, a 2017 randomized study in 56 male soccer players found that treatment with 2 grams of L-arginine daily for 45 days significantly increased sport performance, compared with a placebo group.
Another small study in 9 men demonstrated that those who drank a beverage containing 6 grams of L-arginine 1 hour before intense exercise had significantly increased blood levels of nitric oxide and were able to exercise longer, compared with a placebo group.
However, most studies investigating this relationship have found that L-arginine is not beneficial for improving athletic performance.
L-citrulline, a precursor to L-arginine that’s discussed later in this article, may be a better choice for boosting athletic performance.
Blood pressure regulation:
L-arginine supplements may benefit those with high blood pressure.
Studies have shown that taking L-arginine supplements may help lower both your systolic (the top number) and diastolic (the bottom number) blood pressure readings.
L-arginine is needed for the production of nitric oxide, which is necessary for the relaxation of the cells that make up blood vessels, as well as blood pressure regulation.
A 2016 review of 7 studies found that supplementing with L-arginine by both oral and intravenous (IV) administration significantly reduced systolic and diastolic blood pressure in adults with high blood pressure by up to 5.4 mm/Hg and 3.1 mm/Hg, respectively.
Management of critical illness:
Arginine becomes essential when your body is compromised due to conditions like infection and trauma, and your arginine needs significantly increase due to physiologic demands.
Under these circumstances, your body can no longer fulfill your arginine needs, which must be met through external sources.
Arginine depletion during critical illness or after surgery leads to serious adverse effects, including impaired immune function and blood flow.
To avoid these potential complications, arginine supplements are used frequently in the clinical setting to treat a variety of conditions.
For example, oral or IV arginine is commonly used to treat serious infections like necrotizing enterocolitis in infants, cases of sepsis, burns, chronic disease, and wounds, as well as in pre- and post-surgical and trauma patients.
Blood sugar regulation:
Research shows that L-arginine may benefit those with diabetes by improving glucose metabolism and insulin sensitivity.
L-arginine is needed for the production of nitric oxide.
Nitric oxide plays important roles in cellular function and how your body responds to insulin, a hormone that shuttles blood sugar from your blood into cells, where L-arginine’s used for energy.
Therefore, increasing nitric oxide availability may help enhance the function of cells that secrete insulin and help your body use blood sugar more efficiently.
Some research has shown that long-term treatment with L-arginine supplements may prevent diabetes in at-risk populations.
A study in 144 people with impaired blood sugar regulation found that treatment with 6.4 grams of L-arginine per day for 18 months reduced the chances of diabetes development over a 90-month period, compared with a placebo group.
Traditional/Ethnobotanical uses of L-arginine:
L-arginine is a nonessential amino acid that may play an important role in the treatment of heart disease due to L-arginines block arterial plaque buildup, blood clots, platelet clumping, and to increase blood flow through the coronary artery.
L-arginine is commonly sold as a health supplement claiming to improve vascular health and treat erectile dysfunction in men.
L-arginine, which is promoted as a human growth stimulant, has also been used in bodybuilding.
In the 1800s, L-arginine was first isolated from animal horn.
Use in specific populations of L-arginine:
The safety of L-arginine has been demonstrated in many populations, including pregnant women and older adults.
However, some people, including those with conditions that affect the liver or kidneys, should avoid L-arginine.
L-arginine supplements are sometimes used in children in the clinical setting and deemed safe when prescribed in appropriate doses.
Yet, arginine supplementation in children should always be monitored by a healthcare provider.
L-arginine’s not recommended to give your child L-arginine unless L-arginine’s medically necessary and was suggested by a healthcare provider.
This advice is extremely important to follow, as giving a child too high a dose of L-arginine may result in serious side effects and can even be fata.
Alternatives of L-arginine:
After consumption, your gut and liver rapidly metabolize L-arginine before L-arginine has the chance to reach systemic circulation.
For this reason, some argue that L-citrulline, a precursor to L-arginine, may be a better choice for increasing arginine levels.
L-citrulline is an amino acid that may be used as an alternative to L-arginine when taken as a supplement.
L-citrulline is a nonessential amino acid that’s a precursor to L-arginine.
L-citrulline is converted into L-arginine through a series of enzymatic reactions that take place primarily in your kidneys.
Research shows that L-citrulline supplements can raise body levels of L-arginine.
In fact, some studies show that L-citrulline is more effective at increasing arginine levels than L-arginine supplements.
Research has likewise shown that L-citrulline supplements may offer benefits similar to those of L-arginine supplements.
For example, similarly to L-arginine, L-citrulline has been shown to help reduce blood pressure and improve erectile dysfunction in some studies.
Additionally, studies show that when L-citrulline used on L-arginines own or in combination with L-arginine, L-arginine may improve athletic performance and enhance muscle recovery in athletes.
Furthermore, some of these studies found that citrulline supplements may be more effective than L-arginine supplements at enhancing athletic performance.
Therefore, athletes may benefit more from L-citrulline or a combination of L-arginine and L-citrulline over L-arginine alone.
Benefits of L-arginine:
L-arginine has two effects: L-arginine turns into nitric oxide and helps the body build protein.
These effects give L-arginine an array of potential benefits that range from heart health and chest pain to helping to build muscles, repair wounds, and improve male fertility.
Although there are many claims about the benefits of L-Arginine, not all of them are supported by scientific research studies.
The following are some examples of researched benefits and uses of L-arginine:
Growth hormone reserve test,
Reducing high blood pressure,
Correcting inborn errors of urea synthesis,
Treating heart disease,
Treating erectile dysfunction (ED),
Easing inflammation of the digestive tract in premature infants,
Controlling blood sugar in people with diabetes.
Additionally, L-arginine may have the potential to help with many other issues.
However, more research needs to be done to evaluate further L-arginine’s potential to do the following:
Improve blood flow,
Heal wounds faster,
Alleviate anxiety,
Treat burns,
Improve kidney function for people with congestive heart failure,
Enhance exercise performance.
L-arginine also helps rid the body of ammonia (a waste product) and stimulates the release of insulin.
In addition, your body uses arginine to make nitric oxide (a compound that relaxes the blood vessels).
Although some studies suggest that L-arginine may benefit certain health conditions, other research shows that L-arginine may have harmful effects on some individuals.
Health Benefits of L-arginine:
By improving blood flow in the body, some proponents claim that L-arginine may help heart conditions, such as chest pain (angina), high blood pressure, leg cramping and weakness due to obstructed arteries (a condition known as intermittent claudication), and erectile dysfunction (ED).
Some people use L-arginine to boost the immune system, improve athletic performance, shorten recovery time after surgery, and promote weight loss.
L-arginine is also used for bodybuilding.
There are several additional areas that researchers are interested in exploring regarding L-arginine and L-arginines effects on the human body.
L-arginine is essential for anyone interested in taking L-arginine as a supplement to talk to their doctor about the potential benefits and risks before starting to use L-arginine.
Also, people should fully understand and examine the claims a manufacturer is making about their product before using L-arginine.
Other potential benefits of L-arginine:
In addition to the potential benefits listed above, some research suggests that L-arginine supplements may be helpful when used in the following ways:
Treatment of erectile dysfunction.
A 2019 review of 10 studies found that taking arginine supplements in doses ranging from 1.5–5 grams daily significantly improved erectile dysfunction, compared with a placebo or no treatment.
Improving blood flow.
Some evidence suggests L-arginine supplements may improve blood vessel function and blood flow in specific populations.
However, study results are conflicting, and many have found that L-arginine has no benefit.
Treating and preventing preeclampsia.
Studies have demonstrated that treatment with L-arginine during pregnancy may help prevent and treat preeclampsia, a dangerous condition characterized by high blood pressure and protein in the urine.
This list is not exhaustive, and L-arginine has been studied for L-arginines potential beneficial effects on various conditions, including obesity, heart disease, cancer, polycystic ovary syndrome (PCOS), infertility, and anxiety, either used on L-arginines own or in combination with other supplements.
However, research on the effects of L-arginine in people with these and many other conditions is limited and inconclusive, highlighting the need for future studies.
In addition to the potential benefits and uses above, many people take L-arginine supplements for a variety of other reasons, including reducing the risk of the common cold and boosting weight loss.
Yet, many of these purported benefits aren’t backed by scientific research.
Some people take L-arginine as a supplement.
As with any supplement, a person should use L-arginine with caution.
Although L-arginine is considered safe in moderate doses, too much L-arginine can have severe side effects, including death.
L-arginine is important to understand how the supplement may interact with the body and with additional medications before taking L-arginine.
Overdose of L-arginine:
As mentioned above, arginine is generally considered safe, even when used in high doses.
However, L-arginine’s possible to take too much arginine, which is especially dangerous for children.
Pregnancy and breastfeeding of L-arginine:
L-arginine is used in pregnancy under certain circumstances, including preeclampsia.
L-arginine supplementation during pregnancy is typically prescribed and monitored by a healthcare provider for a specific reason, such as preeclampsia or the risk of preeclampsia and intrauterine growth restriction (IUGR).
There’s some evidence that L-arginine supplements may improve pregnancy outcomes, as well as fetal and maternal health in women from both high- and low-resource areas.
This is because during pregnancy, the body’s need for L-arginine grows due to fetal development and placental growth.
This increased need may not be met through diet, especially in women living in low-resource settings without access to protein-rich foods.
Additionally, although the increased demand for arginine during pregnancy can be provided through diet, protein or individual amino acid supplements may be necessary under certain circumstances.
This may include women who follow restrictive diets or are experiencing severe nausea and vomiting during pregnancy, rendering them unable to meet demands through dietary intake.
However, supplements during pregnancy should always be approved and monitored by a healthcare provider.
If you are pregnant and interested in taking supplemental L-arginine, consult your healthcare provider for advice.
L-arginine supplements have not been researched in breastfeeding women.
For this reason, L-arginine’s important to ask your healthcare provider whether taking L-arginine supplements is safe and necessary for your individual needs during breastfeeding.
History of L-arginine:
Arginine was first isolated in 1886 from yellow lupin seedlings by the German chemist Ernst Schulze and his assistant Ernst Steiger.
He named L-arginine from the Greek árgyros (ἄργυρος) meaning "silver" due to the silver-white appearance of arginine nitrate crystals.
In 1897, Schulze and Ernst Winterstein (1865–1949) determined the structure of arginine.
Schulze and Winterstein synthesized arginine from ornithine and cyanamide in 1899, but some doubts about arginine's structure lingered until Sørensen's synthesis of 1910.
Properties of L-arginine:
Chemical formula: C6H14N4O2
Molar mass: 174.204 g·mol−1
Appearance: White crystals
Odor: Odourless
Melting point: 260 °C; 500 °F; 533 K
Boiling point: 368 °C (694 °F; 641 K)
Solubility in water: 14.87 g/100 mL (20 °C)
Solubility: slightly soluble in ethanol
insoluble in ethyl ether
log P: −1.652
Acidity (pKa): 2.18 (carboxyl), 9.09 (amino), 13.2 (guanidino)
Synonyms of L-arginine:
NCGC00024715-02
NCGC00024715-03
NCGC00024715-04
NCGC00024715-05
NCGC00024715-10
NCGC00260762-01
25212-18-4
4455-52-1
AK-81231
AS-14190
K277
L-Arginine, BioUltra, >=99.5% (NT)
SBI-0207062.P001
AB0014136
A0526
A7079
EU-0100077
L-Arginine, SAJ special grade, >=98.0%
A 5006
C00062
D02982
L-Arginine, Vetec(TM) reagent grade, >=98%
M02981
Y-8965
14932-EP2316830A2
AB00374192_03
Norvaline, 5-[(aminoiminomethyl)amino]-, (L)-
L-arginine
arginine
74-79-3
L-(+)-Arginine
L(+)-Arginine
L-Arg
H-Arg-OH
(S)-2-Amino-5-guanidinopentanoic acid
(L)-Arginine
Arginina
ARGININE, L-
Arginine (VAN)
L-Arginin
Argininum
Arginina
L-Ornithine, N5-(aminoiminomethyl)-
Argamine
Argivene
Detoxargin
Levargin
L-alpha-Amino-delta-guanidinovaleric acid
Minophagen A
1-Amino-4-guanidovaleric acid
CCRIS 3609
NSC 206269
arg
HSDB 1429
AI3-24165
UNII-94ZLA3W45F
MFCD00002635
(S)-2-Amino-5-guanidinovaleric acid
BRN 1725413
CHEBI:16467
(S)-2-Amino-5-((aminoiminomethyl)amino)pentanoic acid
L-Norvaline, 5-((aminoiminomethyl)amino)-
(S)-(+)-arginine
L-Arginine, monohydrochloride
2-amino-5-guanidinovaleric acid
CHEMBL1485
(2S)-2-amino-5-guanidinopentanoic acid
(S)-2-Amino-5-[(aminoiminomethyl)amino]pentanoic acid
94ZLA3W45F
Pentanoic acid, 2-amino-5-((aminoiminomethyl)amino)-, (S)-
(2S)-2-amino-5-(carbamimidamido)pentanoic acid
L-2-Amino-5-guanidinopentanoic acid
Arginine (L-Arginine)
R-Gene
L-Norvaline, 5-[(aminoiminomethyl)amino]-
(2S)-2-amino-5-carbamimidamidopentanoic acid
DSSTox_CID_21056
DSSTox_RID_79618
Poly(L-arginine)
DSSTox_GSID_41056
L(+)-Arginine, 98+%
BDBM181132
HMS3260O15
N5-(aminoiminomethyl)-L-Ornithine
HY-N0455
ZINC1532525
L-Arginine, Vetec(TM), 98.5%
Tox21_113046
Tox21_500077
AC-083
ANW-36527
L-alpha-Amino-delta-guanidinovalerate
L-Arginine, reagent grade, >=98%
s5634
AKOS006239069
AKOS015854096
Tox21_113046_1
AM81500
CCG-204172
DB00125
LP00077
MCULE-5108123240
SDCCGSBI-0050065.P002
L-Arginine, 99%, natural, FCC, FG
(s)-2-amino-5-guanidino-pentanoic acid
5-[(aminoiminomethyl)amino]-L-Norvaline
NCGC00015064-01
NCGC00024715-01
002A635
A837397
Q173670
SR-01000075479
SR-01000597671
(S)-2-amino-5-[(aminoiminomethyl)amino]-Pentanoate
(S)-2-Amino-5-[(aminoiminomethyl)amino]pentanoate
SR-01000075479-1
SR-01000597671-1
W-104410
(S)-2-amino-5-[(aminoiminomethyl)amino]-Pentanoic acid
Arginine, European Pharmacopoeia (EP) Reference Standard
(2S)-2-amino-5-[(diaminomethylidene)amino]pentanoic acid
7F15B0C7-356D-45D7-AC33-03AEE4394A0E
S-(+)-2-Amino-5-[(aminoiminomethyl)amino]pentanoic acid
UNII-0O72R8RF8A component ODKSFYDXXFIFQN-BYPYZUCNSA-N
UNII-FL26NTK3EP component ODKSFYDXXFIFQN-BYPYZUCNSA-N
L-Arginine, United States Pharmacopeia (USP) Reference Standard
L-Arginine, Pharmaceutical Secondary Standard; Certified Reference Material
L-
L-Arginine, from non-animal source, meets EP, USP testing specifications, suitable for cell culture, 98.5-101.0%
L-Arginine, PharmaGrade, Ajinomoto, EP, USP, manufactured under appropriate GMP controls for Pharma or Biopharmaceutical production, suitable for cell culture
