Doctor's Best Pure L-Arginine Powder is an amino acid powder supplement that helps nitric oxide production for improved blood flow and workout performance. The key active ingredient, L-Arginine hydrochloride, acts as a direct precursor to nitric oxide, supporting vasodilation and better blood flow. Doctor's Best has built its reputation since 1990 on science based formulas, transparent labeling, and vegan friendly supplements.

Available Sizes & Variants:

300 grams of L-Arginine powder - ideal for everyday, at home supplementation.

Benefits & Features:

• Supports nitric oxide production for better blood flow and circulation.
• Improves delivery of oxygen and nutrients to muscles during workouts, which can aid performance and recovery.
• Pure, single ingredient formula with no additives, fillers, or artificial colours.
• Suitable for vegan, gluten free and non GM diets, making these supplements accessible to a wide range of users.
• Produced in facilities that follow Good Manufacturing Practices and independently lab tested for ingredient purity and label accuracy, providing ongoing quality assurance and peace of mind you can feel with every scoop.

Doctor's Best has built its reputation on science based formulas since 1990, with transparent sourcing and vegan certification. This L-Arginine powder keeps things simple: a single active ingredient, no fillers, and production in facilities that follow Good Manufacturing Practices. The result is a reliable supplement you can weave into a busy training schedule, whether you’re aiming to push harder at the gym or support daily cardiovascular health.

L-Arginine HCl, L-Arginine HCl

• GTIN: 753950003743
• Manufacturer: Doctor's Best
• Categories: ArginineDoctor's BestL-ArginineNitric Oxide Boosters
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Mix 1 level scoop (approximately 6 grams) in 240 ml of juice or beverage of your choice daily, or as recommended by a nutritionally informed physician. Store in a cool, dry place. Consult your physician before using this product if you are pregnant, lactating, have a medical condition, are on prescription medications, or other supplements that may lower blood pressure while taking this product. Not for use by individuals under the age of 18 years.

Please consult the product packaging for accurate instructions on how to use the product.

*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

The Active Ingredient Is: L-Arginine (L-Arginine Hydrochloride)

L-Arginine is an amino acid that acts as a direct precursor to nitric oxide, a molecule involved in normal blood vessel function and circulation.

This form is L-Arginine hydrochloride, a vegan, gluten-free amino acid supplement with no added fillers, designed for purity and accessibility.

What Does L-Arginine Do?

L-Arginine is involved in the production of nitric oxide, supporting vasodilation and improved blood flow. It also plays a role in supporting energy metabolism related to muscle function and recovery during and after activity.

This product is not intended to diagnose, treat, cure, or prevent any disease.

Welzo chose Doctor’s Best as the supplier for this L-Arginine product based on a thorough, brand-led check of quality, reliability and solid scientific grounding. Doctor’s Best has a long-standing reputation since 1990 for science-based formulations and transparent labeling, which fits our commitment to evidence-led supplementation for the UK market. Their manufacturing philosophy emphasises GMP practices and independent lab verification of ingredient purity and content, showing a high standard of production quality that our team recognises and trusts. This brand’s commitment to vegan, gluten-free and non-GMO formulations further supports safe and allergen-conscious choices for a broad consumer base, matching Welzo’s safety-first approach. For our pick, Doctor’s Best’s single-ingredient L-Arginine powder offers a clean, simple profile ideal for users seeking a pure amino acid option. Our partnership with this brand stems from a clear, expert-driven vetting process in which our medical team checks compliance with our quality certification process. This evaluation is backed by our team of medical experts and our quality certification process.