L-Arginine: benefits, dosage, contraindications
Other name(s)
2-Amino-5-Guanidinopentanoic acid
Scientific name(s)
2-Amino-5-guanidinopentanoic acid
Family or group:
Amino acids
Indications
Rating methodology
EFSA approval.
Angina pectoris ✪✪✪✪✪
Oral intake of L-arginine seems to alleviate symptoms and improve exercise tolerance and quality of life in patients with mild to severe angina. Some patients with severe angina and frequent rest attacks despite treatment with standard anti-anginal agents might also benefit from L-arginine. Doses of 2 to 6 g have been used three times a day for up to one month.
Posologie
Oral
2 - 6 g
1 - month
Adults
Effect of supplementation with long-chain 9-3 polyunsaturated fatty acids on behavior and cognition in children with attention deficit/hyperactivity disorder (ADHD): a randomized placebo-controlled intervention trial.
Clinical and inflammatory effects of dietary L-arginine in patients with intractable angina pectoris.
Effect of supplemental oral L-arginine on exercise capacity in patients with stable angina pectoris.
Effects of oral L-arginine supplementation on exercise-induced QT dispersion and exercise tolerance in stable angina pectoris.
Hypertension ✪✪✪✪✪
It has been proven that oral administration of L-arginine can slightly reduce systolic and diastolic blood pressure in healthy people and patients with mild hypertension. Additionally, L-arginine seems to have additive vasodilatory effects when used with angiotensin-converting enzyme inhibitors or with nitrate derivatives (drugs used in hypertension). Daily oral doses of 4 to 12 g have been used for 2 to 24 weeks.
Posologie
Oral
4 - 12 g
24 - weeks
Adults
Effect of oral L-arginine on blood pressure and symptoms and endothelial function in patients with systemic hypertension, positive exercise tests, and normal coronary arteries.
Effects of L-arginine infusion on renal hemodynamics in patients with mild essential hypertension.
Short-term oral administration of L-arginine improves hemodynamics and exercise capacity in patients with precapillary pulmonary hypertension.
L-arginine in the management of cardiovascular diseases.
Angiotensin-converting enzyme inhibition, but not calcium antagonism, improves a response of the renal vasculature to L-arginine in patients with essential hypertension.
Effect of oral L-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials.
[Pressor, renal and endocrine effects of systemic infusion of L-arginine in hypertensive patients].
Interactions of L-arginine, isosorbide mononitrate, and angiotensin II inhibitors on arterial pulse wave.
Oral arginine reduces systemic blood pressure in type 2 diabetes: its potential role in nitric oxide generation.
Blood pressure and metabolic changes during dietary L-arginine supplementation in humans.
Pregnancy ✪✪✪✪✪
Most researches show that L-arginine is beneficial for patients with pre-eclampsia (gestational hypertension). Indeed, taking 3 g orally for 3 weeks reduces systolic and diastolic blood pressure in pregnant women with hypertension compared to placebo. L-arginine also seems to prevent pre-eclampsia. A clinical study showed that taking L-arginine at 3 g per day from the 20th week of gestation reduced the risk of pre-eclampsia by about 74% compared to placebo, in high-risk women.
Posologie
Oral
3 g
3 - weeks
Pregnant women
L-arginine supplementation in women with chronic hypertension: impact on blood pressure and maternal and neonatal complications.
Therapeutic Benefits of L-Arginine: An Umbrella Review of Meta-analyses
Effects of acute L-arginine infusion on non-stress test in hypertensive pregnant women.
L-arginine supplementation in patients with gestational hypertension: a pilot study.
Effect of L-arginine therapy on the glomerular injury of preeclampsia: a randomized controlled trial.
Effect of L-arginine on blood pressure in pregnancy-induced hypertension: a randomized placebo-controlled trial.
Arginine supplementation for improving maternal and neonatal outcomes in hypertensive disorder of pregnancy: a systematic review
Effects of prolonged oral supplementation with l-arginine on blood pressure and nitric oxide synthesis in preeclampsia.
Dietary supplementation with L-arginine or placebo in women with pre-eclampsia.
Type 2 diabetes ✪✪✪✪✪
The intake of 3 grams of L-arginine orally three times a day for one month appears to improve insulin sensitivity in patients with type 2 diabetes. Further preliminary clinical research shows that taking 8 grams of L-arginine orally with meals increases postprandial insulin secretion in patients with type 2 diabetes. In a recent randomized, double-blind, placebo-controlled study conducted on subjects with glucose intolerance and metabolic syndrome, supplementation with arginine (6.4 g/day) for 18 months did not reduce the incidence of diabetes, but it significantly improved glucose tolerance due to better insulin sensitivity and improved beta cell function.
Posologie
Orally
6.4 - 9 g
Adults
Long-term oral L-arginine administration improves peripheral and hepatic insulin sensitivity in type 2 diabetic patients
Evaluation of beta cell dysfunction by mixed meal tolerance test and oral L-arginine in patients with newly diagnosed type 2 diabetes mellitus
Intermittent claudication ✪✪✪✪✪
Clinical evidence shows that short-term use of L-arginine (up to 8 weeks) increases arterial dilation and improves intermittent claudications associated with peripheral arterial disease. However, long-term administration of L-arginine orally for 6 months does not improve walking speed and distance in patients with peripheral arterial disease. L-arginine has been used daily at 6 to 24 grams in divided doses for 8 weeks.
Posologie
Orally
6 - 24 g
8 - weeks
Adults
ADMA and oxidative stress are responsible for endothelial dysfunction in hyperhomocyst(e)inemia: effects of L-arginine and B vitamins
A pilot study of L-arginine supplementation on functional capacity in peripheral arterial disease
L-arginine in the management of cardiovascular diseases
L-arginine supplementation in peripheral arterial disease: no benefit and possible harm
Restoring vascular nitric oxide formation by L-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive disease
Erectile dysfunction ✪✪✪✪✪
Most clinical research shows that taking L-arginine orally can improve symptoms of erectile dysfunction. In a clinical trial, taking 5 grams of L-arginine daily for 8 weeks enhances desire, orgasm, and sexual satisfaction approximately twice as much as placebo. There is also evidence that taking L-arginine in combination with phosphodiesterase type 5 (PDE5) inhibitors (a treatment that facilitates erection) improves symptoms of erectile dysfunction. Clinical research shows that taking 5 grams of L-arginine daily in combination with 10 mg/day of tadalafil (a PDE5 inhibitor) for 8 weeks improves erectile function by about 83%, which was more effective than L-arginine or tadalafil alone, in patients with type 2 diabetes and mild to moderate erectile dysfunction. A dose of 2.5 to 5 grams of L-arginine daily has been used for up to 12 weeks.
Posologie
Orally
2.5 - 5 g
3 - months
Men
Clinical assessment of a supplement of Pycnogenol ae and L-arginine in Japanese patients with mild to moderate erectile dysfunction.
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.
Sports performance ✪✪✪✪✪
Several researchers believe that arginine can improve physical performance since it stimulates the secretion of growth hormone (GH) and contributes to the production of creatine, a substance playing an important role in muscle contraction. Moreover, clinical research shows that L-arginine seems to increase exercise endurance, but not strength, when used for sports performance. Indeed, some clinical research on healthy and active men shows that taking 6 grams of L-arginine increases the time to exhaustion during high-intensity exercise compared to placebo. Research on male soccer players shows that taking 2 grams of L-arginine daily for 45 days increases maximal oxygen uptake and thus cardiorespiratory capacity approximately 3.3 times more than placebo. However, it does not affect lean mass. Other research on male soccer players shows that taking 1.2 grams of L-arginine and 1.2 grams of L-citrulline daily for 7 days increases total power on a 10-minute cycling test and improves subjective perceptions of exertion compared to placebo.
Posologie
Orally
1.2 - 6 g
Adults
Obesity ✪✪✪✪✪
Preliminary clinical research suggests that taking L-Arginine at 3 grams orally three times a day for 12 weeks, in addition to following dietary advice, reduces waist circumference by 4-6 cm and weight by 1.8-2.9 kg in obese women aged 18 to 40 years.
Posologie
Orally
9 g
12 - weeks
Adults
Wounds ✪✪✪✪✪
A number of studies have shown that supplementation with l-arginine improves wound healing. Indeed, a randomized controlled study showed that taking 17 g/day of arginine in the form of arginine aspartate for 14 days improved healing in healthy older adults. Another study conducted on healthy adults showed improvement in surgical wounds with a dose of 17 to 25 g per day of arginine orally.
Posologie
Orally
17 - 25 g
14 - days
Adults
Cancer ✪✪✪✪✪
Enteral nutrition supplemented with L-arginine appears to reduce wounds and general infections following surgery in patients with head and neck cancer, but it does not seem to have beneficial effects on immune function markers such as interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) and postoperative hospital stay duration. Another prospective randomized study conducted on patients with head and neck cancer who had recent weight loss showed that postoperative intake of an oral supplement containing omega-3 fatty acids and arginine for 12 weeks, was beneficial with an improvement in biomarker levels, such as albumin, prealbumin, and lymphocytes, and an improvement in weight gain. Enteral nutrition supplemented with L-arginine at a rate of 0.81 to 1.3 grams has been used.
Posologie
Orally
0.81 - 1.3 g
Adults
A randomized clinical trial with two doses of a omega 3 fatty acids oral and arginine enhanced formula in clinical and biochemical parameters of head and neck cancer ambulatory patients
Effect of c-reactive protein and interleukins blood levels in postsurgery arginine-enhanced enteral nutrition in head and neck cancer patients
Properties
Antioxidant
L-arginine has antioxidant effects and may reduce lipid peroxidation. It could prevent damage caused by oxidative radicals under certain conditions, notably in myocardial ischemia, atherosclerosis, and stress.
Usages associés
Cardiovascular
Nitric oxide produced from L-arginine induces vasodilation which might be responsible for a slight reduction in blood pressure. L-arginine also reduces the activity of the angiotensin-converting enzyme, thus decreasing the conversion of angiotensin-I into angiotensin-II. Angiotensin II is a vasoconstrictor. Consequently, the antihypertensive effects of L-arginine may be attributed to the reduced conversion of angiotensin I. Finally, L-arginine can reduce blood viscosity by decreasing platelet aggregation.
Usages associés
Metabolic
Diabetic individuals seem to have lower than normal levels of L-arginine. L-arginine can help increase glucose clearance, enhance insulin sensitivity and raise postprandial plasma insulin levels in diabetic and pre-diabetic patients. In animals, dietary L-arginine appears to increase lipolysis.
Usages associés
Fertility effect
In vitro research suggests that nitric oxide from L-arginine may stimulate sperm motility and metabolism in men suffering from asthenospermia. Additionally, nitric oxide is involved in erectile function.
Usages associés
Anticancer
There is evidence that L-arginine modifies immune system function and may potentiate tumor cell response to anticancer drugs and possibly reduce the immunosuppressive effects of chemotherapy agents. L-arginine appears to increase lymphocyte reactivity to polyclonal mitogenic agents and may also enhance natural cytotoxicity. However, L-arginine also promotes tumor growth by providing a nitrogen source and in certain situations, the nutritional value of L-arginine may outweigh its antitumor effects.
Usages associés
Neurological
Animal research shows that L-arginine intake in rats suffering from drug-induced seizures increases the delay before the first seizure and decreases mortality due to seizures. This effect may be due to increased nitric oxide levels from L-arginine.
Healing
L-arginine is metabolized into L-ornithine, then into L-proline, which is utilized in collagen synthesis and wound healing
Usages associés
Safety dosage
Adult: 1.5 g - 30 g
L-arginine is taken in doses of 1.5 to 6 g per day in divided doses to improve absorption. L-arginine has been used safely at doses up to 30 g per day for 18 months according to clinical studies.
Pregnant woman: 12 g
L-arginine has been used at a dose of 12 g per day for 2 days, with apparent safety, in pregnant women during the third trimester. Lower doses have also been used safely for up to 8 weeks.
Interactions
Médicaments
Antihypertensives: moderate interaction
The combination of L-arginine with certain antihypertensives, particularly angiotensin-converting enzyme (ACE) inhibitors, seems to have additive effects on vasodilation and blood pressure reduction. Theoretically, the concurrent use of L-arginine and ACE inhibitors may increase the risk of low blood pressure.
Antidiabetics: moderate interaction
Preliminary research in humans suggests that L-arginine decreases blood glucose levels in patients with type 2 diabetes. Theoretically, concurrent use of L-arginine may require dosage adjustment of antidiabetic medications.
Diuretics: moderate interaction
Potassium-sparing diuretics can increase potassium levels. The use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concurrent use may increase the risk of hyperkalemia.
Sildenafil: moderate interaction
In vivo, the concurrent use of L-arginine and sildenafil has led to an increase in vasodilation. Theoretically, concurrent use could lead to hypotension. However, this interaction has not been reported in humans.
Nitrates: moderate interaction
Theoretically, concurrent use may cause additive vasodilation and have a hypotensive effect. Use with caution.
Precautions
Breastfeeding women: avoid
It is preferable to avoid the use of L-arginine in breastfeeding women due to lack of reliable information.
Liver disorders: use with caution
Metabolic acidosis associated with arrhythmia and hyperkalemia and increased blood urea may occur in patients with liver disease and/or renal failure.
Hypotension: avoid
L-arginine increases nitric oxide, which causes vasodilation. Theoretically, L-arginine could worsen hypotension.
Renal failure: use with caution
Metabolic acidosis associated with arrhythmia and hyperkalemia and increased blood urea may occur in patients with liver disease and/or renal failure.
Herpes: use with caution
Theoretically, L-arginine could exacerbate herpes. Preliminary evidence suggests that L-arginine may be required for viral replication.
Contraindications
Myocardial infarction: prohibited
It is feared that L-arginine may increase mortality when taken by patients following a myocardial infarction. Researchers believe that L-arginine could increase reactive oxygen species and homocysteine levels.
