NOW Foods ARGININE 1000mg (Double Strength, 120 Tablets)
Pharmaceutical-grade free-form amino acid engineered to promote natural nitric oxide production, healthy circulation, and cardiovascular wellness.
Quick Summary: L-Arginine is a vital building block your body uses to create nitric oxide—a natural compound that relaxes blood vessels and keeps blood moving freely. Each single tablet provides a full 1,000 mg of double-strength L-Arginine (derived from 1,250 mg of L-Arginine HCl), twice the potency of standard 500 mg capsules. Sourced and distributed through VitaNet, LLC, serving customers nationwide since 1995 from Hartville, Ohio[cite: 1].
How L-Arginine 1000 mg Works in Your Body: The Nitric Oxide Engine
L-Arginine is what nutrition scientists call a conditionally essential amino acid. While your body can synthesize small quantities on its own, times of intense physical exertion, cardiovascular strain, or metabolic demand require higher amounts than standard food intake can supply.
Think of your vascular system like a network of flexible garden hoses. When the lining of your blood vessels receives L-Arginine, an enzyme called endothelial nitric oxide synthase (eNOS) converts it into nitric oxide (NO) gas. Nitric oxide signals the smooth muscle cells surrounding your arteries to soften and relax—a process called vasodilation.
Primary Physiological Benefits Supported by Clinical Research:
Vascular Elasticity & Healthy Blood Pressure: By signaling blood vessels to dilate, oral L-Arginine supplementation helps maintain normal systemic vascular resistance and healthy systolic and diastolic blood pressure ranges (American Heart Journal, Dong et al., 2011; 162(6):959-965).
Exercise Oxygen Delivery & Muscle Recovery: Dilated vessels deliver nutrient-rich, oxygenated blood directly to hard-working muscle tissues while rapidly flushing out cellular metabolic byproducts like lactic acid and ammonia (Journal of Applied Physiology, Bailey et al., 2010; 109(5):1394-1403).
Natural Urea Cycle Detoxification: Arginine serves as a mandatory intermediate in the liver's urea cycle, helping your body convert toxic excess ammonia into harmless urea for safe kidney elimination.
Cellular Protein Synthesis & Tissue Repair: It acts as an indispensable nitrogen donor for cellular DNA synthesis and systemic tissue rebuilding.
NOW Foods Lab Testing & Strict Contaminant Constraints
Many generic brands on mass-market platforms repackage untested raw powders from anonymous brokers. NOW Foods operates one of the most advanced private analytical testing facilities in the dietary supplement industry, conducting over 19,000 analytical tests every month across their Bloomingdale, Illinois, and Sparks, Nevada facilities.
State-of-the-Art Analytical Instrumentation Behind Every Tablet:
Heavy Metal Screening via ICP-MS: NOW uses Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to detect trace elemental toxicities down to parts-per-billion (ppb). Every production batch must pass limits for Lead, Arsenic, Cadmium, and Mercury that comply with stringent California Proposition 65 limits (Lead < 0.5 mcg/day)—standards far stricter than baseline federal regulations.
Potency & Amino Acid Fingerprinting via HPLC & UPLC: High-Performance Liquid Chromatography separates and quantifies the active amino acid molecules to ensure that every single tablet delivers 100% of the stated 1,000 mg of L-Arginine, confirming zero degradation and zero filler spiking.
Residual Solvent Detection via GC-MS: Gas Chromatography-Mass Spectrometry guarantees that no volatile organic chemical solvents used during the crystallization of L-Arginine HCl carry over into the finished product.
Stringent Microbiological & Pathogen Screening: Every lot is validated by automated microbiology plating to confirm the absolute absence of Salmonella spp., Escherichia coli, and Staphylococcus aureus, while maintaining total yeast, mold, and aerobic microbial plate counts well within United States Pharmacopeia (USP) specifications.
NOW Foods manufacturing facilities are audited and certified under Underwriters Laboratories (UL) Good Manufacturing Practices (GMP) and maintain ISO/IEC 17025 accreditation for laboratory competence.
Complete Supplement Facts & Ingredient Listing
We believe in 100% label transparency. Double-checked against official NOW Foods manufacturing records (Item # 0035 / Vitanet N0035):
Not manufactured with: wheat, gluten, soy, milk, egg, fish, shellfish, tree nuts, or sesame ingredients. Facility standard: Produced in an audited GMP facility that processes other ingredients containing these allergens. Form: Pharmaceutical Grade free-form L-Arginine. Suitable for vegetarians and vegans.
How to Take L-Arginine 1000 mg for Maximum Absorption
Amino acids do not absorb like standard vitamins. Because L-Arginine shares intestinal transport channels with other dietary amino acids (such as lysine, valine, and leucine), following these simple rules prevents nutrient competition and optimizes results:
1. Suggested Dosage & Frequency
Take 1 tablet 1 to 2 times daily as needed. Because this double-strength formula packs 1,000 mg into each tablet, a single morning and evening tablet is sufficient for most adults without needing handfuls of pills.
2. The "Empty Stomach" Advantage
Always take your tablet between meals or right at bedtime. If taken with a heavy protein meal (like steak, chicken, or eggs), those competing amino acids will crowd out the L-Arginine, drastically cutting down how much enters your bloodstream.
3. Hydration & Carbohydrate Transport
Swallow each tablet with at least 8 ounces of water or fruit juice. A small amount of carbohydrates triggers a mild insulin release that actually helps shuttle free amino acids directly into muscle and vascular tissue.
Crucial Safety Cautions, Medical Contraindications & Interactions
Because L-Arginine exerts real, active effects on blood pressure and blood flow, responsible health guidance requires reviewing when this supplement is not appropriate.
Do not use L-Arginine if you have had a recent heart attack (myocardial infarction) or have established coronary artery disease, unless explicitly managed by your cardiologist. In the landmark clinical trial published in the Journal of the American Medical Association (Schulman et al., 2006; 295(1):58-64), high-dose L-Arginine supplementation following acute myocardial infarction failed to improve vascular stiffness and was associated with unfavorable clinical outcomes.
Other Important Health Considerations & Prescription Drug Interactions:
Blood Pressure Medications (Antihypertensives): Because L-Arginine naturally relaxes arterial walls, combining it with prescription blood pressure medications (such as ACE inhibitors, ARBs, or beta-blockers) can cause an additive effect, leading to dizziness or hypotension (abnormally low blood pressure). Consult your prescribing doctor to monitor your levels.
Erectile Dysfunction Drugs (PDE5 Inhibitors): Medications like sildenafil (Viagra) or tadalafil (Cialis) also work via the nitric oxide pathway. Taking large doses of L-Arginine concurrently can cause sudden, dangerous drops in blood pressure.
Herpes Simplex Virus (Cold Sores / HSV): The Herpes simplex virus requires L-Arginine to replicate inside cells, while another amino acid, L-Lysine, suppresses viral growth (Dermatologica, Griffith et al., 1981; 163(4):315-321). If you are prone to frequent cold sores or shingles, supplementing with arginine may trigger an outbreak unless counterbalanced with supplemental lysine.
Kidney Disease & Asthma: Individuals with renal insufficiency may have difficulty clearing nitrogenous wastes or regulating potassium levels. Those with active asthma should use caution, as arginine can alter airway responsiveness.
Upcoming Surgery: Discontinue L-Arginine at least two (2) weeks prior to any scheduled surgical or dental procedure to avoid interfering with vascular tone and blood pressure stability during anesthesia.
Why Choose VitaNet, LLC for Your NOW Supplements?
In an era where online marketplaces allow unvetted third-party sellers to store heat-sensitive vitamins in uncontrolled warehouses, where you buy matters just as much as what you buy.
Family-Owned Independent Heritage[cite: 1]
VitaNet, LLC has been serving customers online since 1995 with over 31 years of dedicated, hands-on nutritional experience from our headquarters at 887 Edison Street Northwest in Hartville, Ohio[cite: 1].
BBB A+ Accredited Business[cite: 1]
We hold an A+ rating with the Better Business Bureau, maintaining authentic customer service with real phone support (330-877-8786) and direct manufacturer distribution relationships[cite: 1].
100% Risk-Free Money-Back Guarantee[cite: 1]
Every product is backed by our unconditional 100% money-back guarantee—we even pay the return shipping costs on opened bottles if you are not completely satisfied with your purchase[cite: 1].
Frequently Asked Questions (FAQ)
What is the difference between regular L-Arginine 500 mg and this Double Strength 1000 mg tablet?
Standard L-Arginine supplements typically provide 500 mg per capsule, requiring you to swallow multiple pills throughout the day. NOW Foods ARGININE 1000mg uses a high-density, double-strength formulation providing 1,000 mg of pure pharmaceutical-grade L-Arginine (from 1,250 mg L-Arginine HCl) in a single tablet, cutting your daily pill count in half while ensuring consistent blood concentrations.
Why must I take L-Arginine between meals or with a carbohydrate drink?
Amino acids utilize shared carrier channels in your intestinal lining. When consumed alongside protein-heavy meals, other dietary amino acids compete for the same absorption pathways, drastically reducing the amount of arginine that enters your bloodstream. Taking it on an empty stomach with water or a small splash of juice ensures rapid, uninterrupted uptake into vascular tissue.
How does NOW Foods test this L-Arginine for heavy metals, purity, and contamination?
NOW Foods tests raw ingredients and finished lots using in-house ISO/IEC 17025 accredited laboratories. Every batch is analyzed via Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for heavy metals (Lead, Arsenic, Cadmium, Mercury), High-Performance Liquid Chromatography (HPLC) to verify 100% active potency, and Gas Chromatography (GC-MS) to ensure zero residual solvent contamination.
Can taking L-Arginine trigger cold sores or herpes flare-ups?
Yes, this is a known biochemical reaction. The Herpes simplex virus requires L-Arginine to replicate. If you carry the virus or are prone to cold sores, an excess of arginine relative to lysine can trigger an outbreak. If this happens, you should reduce your arginine dose, consult your physician, or consider balancing your routine with supplemental L-Lysine.
Can I take NOW L-Arginine 1000 mg if I have high blood pressure or take heart medications?
You must consult your physician before taking L-Arginine if you take prescription blood pressure medications (antihypertensives) or nitrates, as arginine can enhance their blood pressure-lowering effect. Furthermore, L-Arginine is strictly contraindicated for individuals who have experienced a recent heart attack (myocardial infarction) or have severe coronary artery disease.
What is VitaNet's return policy if this supplement does not suit my routine?
VitaNet, LLC offers an unconditional 100% money-back guarantee on all products[cite: 1]. If you are dissatisfied for any reason, VitaNet will refund your purchase and even pay the return shipping costs, even on opened bottles[cite: 1].