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Now Foods, Arginine & Citrulline, 500/250, 120 Capsules

Now Foods, Arginine & Citrulline, 500/250, 120 Capsules

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In Stock
  • Expiration Date: Feb 2020
  • Shipping Weight:
    0.41 lbs
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  • Product Code: NOW-00037
  • UPC Code: 733739000378
  • Package Quantity: 120 Capsules
  • Dimensions:
    2.7 x 2.7 x 4.6 in, 0.35 lbs
    Switch to Metric units
Product Overview


  • Sports
  • Supports Protein Metabolism
  • Helps Maintain Muscle Tissue
  • GMP Quality Assured
  • A Dietary Supplement

Arginine and Citrulline are two amino acids that are integral to protein metabolism and utilization, as well as to the maintenance of muscle tissue. Both are key intermediates in the urea cycle, where they participate in the detoxification of ammonia via the production of urea. Arginine that has not been converted to urea enters general circulation where it is distributed to various tissues and metabolized for other uses such as protein synthesis. Scientific studies have shown that supplementing Citrulline along with Arginine helps maintain nitrogen balance better than supplementation with Arginine alone.

Suggested Use

As a dietary supplement, take 2 capsules 1 to 3 times daily as needed, preferably with juice or water on an empty stomach, before exercise or at bedtime. Consider taking this product in combination with NOW L-Norvaline, P-5-P and AAKG.

Other Ingredients

Gelatin (capsule) silica, cellulose, stearic acid (vegetable source) and magnesium stearate (vegetable source).

Contains no sugar, salt, starch, yeast, wheat, gluten, corn, soy, milk, egg, shellfish or preservatives.


Do not eat freshness packet. Keep in bottle.

Store in a cool, dry place. Please recycle.

This supplement should be avoided by persons with glaucoma or herpes simplex unless otherwise prescribed by a physician. Do not use if you have had a myocardial infarction or have established coronary artery disease.

Supplement Facts
Serving Size: 2 Capsules
Servings Per Container: 60
  Amount Per Serving % Daily Value
L-Arginine (Free-Form) 1.0 g (1,000 mg) *
L-Citrulline (Free-Form) 500 mg *
* Daily Value not established.
iHerb Customer Reviews

great product, subtle effect but good anyway

Posted by 4948347269892280796 on Mar 13, 2017 | Verified Purchase

I am a coeliac sufferer, and some other fish oil combinations are not kind to my digestive system, this one is, As prescribed by my doctor, it is part of a group of supplements that that assist with my digestion, absorption of nutrients and healthy intestinal flora

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Just started

Posted by 5207670714953253399 on Oct 21, 2016 | Verified Purchase

About an hour after ingestion I get a sort of rush that settles down 1/2 an hour later. I am not taking this to lose weight or gain muscle, rather to jump-start a sluggish metabolism, and it seems to be working. No after taste, quality product and packaging.

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compromised product??

Posted by Reviewer1642736 on Oct 10, 2012 | Verified Purchase

I just ordered this product on 10/8/12 and received it on10/10/12. i open the package that the bottle was shipped in and the unopened bottle looks like the capsules have broken open inside the still sealed bottle. never had this problem before, not really happy with the situation. Just spoke to customer service via live chat and problem is already resolved, great like the quick response

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too subtle, but good for muscle soreness for me

Posted by Reviewer1733570 on Jul 20, 2012 | Verified Purchase

I haven't noticed increased energy or pumps, I've also hoped this might have helped my bad peripheral circulation but there were no improvements felt. I did however notice that muscle soreness was significantly reduced after working out on this which is why I give 3 stars.

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Posted by Reviewer2906996 on Jul 01, 2012 | Verified Purchase

This supplement has greatly helped my irregular heart beat and angina. Been able to greatly reduce the amount of nitroglycerin i take for controlling those.

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