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NOW L-Arginine 500mg (100 capsules)
NOW L-Arginine 500mg (250 capsules)
NOW Extra Strength L-Arginine, 100mg (120 tablets)
454g Jar of NOW Free form L-Arginine Powder

NOW - L-Arginine

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Info: Available in 2 Strengths and Quantities

L-Arginine is one of the most versatile amino acids in our bodies, which helps our cells synthesize proteins, nitric oxide, urea, polyamines, proline, glutamate, creatine and agmatine. One of its first and perhaps most important identified function is in helping to create urea in order to excrete toxic ammonia from the body, but it also helps make nitric oxide (NO), a relaxing factor which regulates vascular tone and blood flow.

Product Notes:

Although our bodies normally make enough arginine on their own, people with protein malnutrition or excessive ammonia production may not; similarly for those with excessive lysine intake, burns, infections, peritoneal dialysis, rapid growth, urea synthesis disorders, or sepsis. Symptoms of arginine deficiency include poor wound healing, hair loss, skin rash, constipation, and fatty liver.

Alternatively, many body builders take it because it can also help produce creatine, an energy substrate for muscles, plus it can increase anabolic hormones such human growth hormone (HGH) and glucagon. Those users may prefer to take it in the powdered form.

A 454 gram jar (733739802101) of Free form L-Arginine Powder may also available by request; please contact us for details.


Each capsule (NPN: 80002671) contains:
500 mg L-Arginine.

Non-Medicinal Ingredients: Capsule (gelatin, water), Magnesium Stearate (vegetable source).

Each Tablet (NPN: 80002670) contains:
1000 mg L-Arginine (from L-Arginine HCl)

Non-medicinal ingredients: Microcrystalline Cellulose, Stearic Acid (vegetable source), Silica, Croscarmellose Sodium, Tablet Coating (hypromellose, stearic acid, cellulose).

Each Level Teaspoonful (15 ml) of the Powder (NPN: 80024998) contains:
2,300 mg L-Arginine (no other ingredients).

The L-Arginine used in these products is Pharmaceutical Grade (USP).

Suggested Usage:

Adults: Take two 500 mg Capsules 1 to 3 times daily as required, between meals, or at bedtime with a carbohydrate drink to facilitate absorption. Or,

Adults: Take one 1,000 mg Tablet 1 to 3 times daily, between meals or at bedtime with a carbohydrate drink to facilitate absorption. Do not use beyond 8 weeks. Or,

For the Powder: Adults: For Protein Synthesis: Take 1 to 3 level teaspoons (2.3 to 6.9G), one to 3 times per day between meals, or at bedtime with a drink. Do not exceed 8 g per single dose, or 21 g per day.

For Improvement in Exercise Capacity in individuals with stable CVD: Take 2 to 3 level teaspoons (4.6 to 6.9 g), two to three times per day between meals or at bedtime with a drink. Do not exceed 8 g per single dose, or 21 g per day.

Consult a healthcare practitioner for use beyond 12 weeks.

For each type, keep bottle tightly closed, and store in a cool, dry place.


Capsules and Tablets: Do not use if you have gout, decreased platelet count, elevated blood-urea-nitrogen, serum creatine and creatinine, delayed menses, asthma, or if you are pregnant or breastfeeding. Also do not use if you have had a myocardial infarction (heart attack) or have established coronary artery disease.

Consult a healthcare practitioner prior to use if you have human herpes virus, sickle cell anemia, are taking antihypertensives, cyclosporine, estrogens, birth control medications, medroxyprogesterone, norethindrone, nitrates, potassium-increasing drugs, sildenafil, xylitol, and/or aminophyllins.

Powder: Do not use if you have had a heart attack/myocardial infarction. Consult a healthcare practitioner prior to use if you are pregnant or breastfeeding, if you have a renal/kidney disease, or if you are following a low protein diet, if you suffer from a cardiovascular disease and are attempting an increase in physical activity, or if you are taking medication for cardiovascular diseases, erectile dysfunction, and/or blood thinners. Some people may experience gastrointestinal discomfort (such as diarrhea).

The Benefits of L-Arginine

L-arginine is an amino acid classified as "semi-essential," which means the body can make adequate amounts for proper health from the kidneys and liver. But to obtain maximal benefits, additional supplementation is required. (In case you are curious, the 'L' at the beginning of L-arginine means it is one of the most common amino acids.)

L-arginine performs many functions in the human body. It's a protein building block that helps the pituitary gland function, supports the immune system, helps wounds heal, aids blood flow, lowers cholesterol, balances levels of sodium, fights build-up of plaque, and eliminates waste products. There is also evidence showing L-arginine can relieve migraine headaches, metabolize fat, and raise good cholesterol levels. It even creates other amino acids and substances such as creatine, L-proline (which is responsible for helping wounds heal), and L-glutamine, which can be converted into energy if the body requires it. L-arginine is also thought to improve one's sense of smell, and help long term memory.

One of the most beneficial aspects of L-arginine is that it acts as a precursor to a gas called nitric oxide. Nitric oxide causes blood vessels to engorge and dilate through a relaxation process known as vasodilation, which can aid sexual performance in both men and women. If L-arginine is taken with yohimbe or ginkgo biloba, it can even be effective at treating erectile dysfunction. Dilated and engorged blood vessels from vasodilation also relieve stress on the heart.

Because L-arginine production lessens with age, some researchers believe the loss speeds up various degenerative processes. Hence, it's important to get enough of the amino acid since it can act as a mild anti-aging nutrient.

Body builders take L-arginine because it gives them a fuller muscular "pump" during workouts. There is also evidence showing it helps secretion of normal hormones, as well as the release of natural growth hormone, which bodybuilders and fitness enthusiasts find especially appealing. L-arginine also removes toxins from the body and supports a healthy immune system, which allows athletes to recover faster. But here is a warning: If you regularly consume protein shakes, as many bodybuilders do, be aware that many manufacturers add additional amino acids to their powders, so be careful not to overdose.

Although there are no precise guidelines for amounts of L-arginine to take, it's recommended to stay lower than 2000 milligrams per day. And if you have a heart condition or a mental health issue, consult a medical professional before taking L-arginine. Side effects from large amounts are thickening of the skin, nausea, diarrhea, and fatigue. But these will go away when dosages are lowered. L-arginine in higher amounts can also create stomach acid, which sometimes irritates ulcers and heartburn. Also consult a doctor if you take blood pressure medication, since L-arginine alters potassium levels in the body. If you are a diabetic, seek advice from a medical professional since L-arginine also raises blood sugar.

There are many natural food sources for L-arginine if you don't like pills. Poultry, beef, lobster, shrimp, salmon, pumpkin seeds, sesame seeds, cottage cheese, soybeans, oatmeal, chocolate, peanuts, raisins, almonds, and other nuts.

In summary, almost everyone can benefit from taking L-arginine. Athletes, people on diets, older people to hinder the aging process, those with high cholesterol levels, etc. So be sure to start your supplementation regimen as soon as you can.

Barcodes for each NOW product:

L-Arginine 500mg (100 capsules): 733739800305
L-Arginine 500mg (250 capsules): 733739800312
L-Arginine 1000 mg (double strength) (120 tablets): 733739800350
Free form L-Arginine Powder (454 g): 733739802101

Product Options:
500 mg Strength, 100 Capsules - $14.99 - UPC: 733739800305
500 mg Strength, 250 Capsules - $27.99 - UPC: 733739800312
1000 mg Strength, 120 Tablets - $29.99 - UPC: 733739800350