Ingredient 3 of 3
L-Arginine HCl in Melonex: Third in the Blend, 167 mg at Most
L-arginine HCl is the third and last name in the Melonex blend, so by label order it is at most 167 mg of the 500 mg. It is arginine bound to hydrochloric acid, which makes it dissolve well. Trials of arginine used grams a day; 167 mg is a small fraction of that.
Written by the Melonex label deskUpdated
What is L-arginine HCl?
It is the amino acid arginine joined to hydrochloric acid to form a salt. The salt dissolves well in water and is a common way to supply arginine.
| Name on the label | L - Arginine HCL |
|---|---|
| What it is | Amino acid arginine as its hydrochloride salt |
| Place in the blend list | 3 of 3, most to least by weight |
| Amount per capsule | not printed; the label order caps it at 167 mg of the 500 mg blend |
| Amount used in research | Pooled trials of L-arginine alone mostly used grams a day; no further change above 9 g a day |
| Strength of evidence | Small average drops in pooled trials of arginine alone; Mayo says it might help, MSK calls the evidence mixed and limited |
| Marketed or traditional use | Sold for blood-vessel support |
| Main caution | Not recommended after a recent heart attack (Mayo, MSK, Cleveland Clinic). Can add to blood-pressure medicines; Mayo also names nitrates, sildenafil and potassium-sparing diuretics. |
The body uses arginine as the raw material for nitric oxide, which helps relax the muscle in blood vessel walls 6. Taken by mouth, much arginine is broken down in the gut and liver before it reaches the blood, which is one reason researchers also study citrulline 7.
Where is it in the Melonex blend?
It is last in the list. The label order caps it at 167 mg of the 500 mg, and the real amount is not printed.
Because the HCl part adds weight, the arginine itself is less than the line. Two of the three names are arginine forms, so arginine is a major part of the blend, but the label does not tell you how much. See the proprietary blend page.
What does arginine research show?
Pooled trials show small average drops in blood pressure at gram doses, with large differences between studies. Heart-attack patients were harmed in one trial.
| Source | What it says |
|---|---|
| NCCIH | Some research suggests oral arginine may lower blood pressure; evidence is mixed and limited 1 |
| Memorial Sloan Kettering | Evidence is mixed and limited; no benefit in heart-attack patients 2 |
| Drugs.com | Lists uses but reports no solid support for them 3 |
| Meta-analysis, 22 trials | Systolic -6.40 mm Hg at gram doses 5 |
| VINTAGE MI trial | 153 people after a first heart attack; stopped early 4 |
These findings are about arginine taken in grams a day, not about this capsule. They support careful wording, not a promise.
How does 167 mg compare with trial doses?
It is a fraction. The meta-analysis looked at doses of grams a day; the label ceiling is under two tenths of a gram.
Even if all three lines were arginine, which they are not, two capsules a day would be 1 g of blend. Reading trial results as a promise about this product would be wrong.
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See packsHow do you read arginine HCl on the whole label?
Read it as one line out of three, under a total of 500 mg, with a plain rule about order and no promise about amount.
The label gives three facts: the name, its place and the total. It leaves out the milligrams of this line, the source of the ingredient, and any lab result. The brand's claims on the front, Heart Support* and Circulation Support*, are starred to the FDA statement that the claims are not evaluated and that the product is not meant to treat, cure or prevent any disease 10.
That matters because it is easy to move from "arginine relaxes vessels" to "so the capsule does this for me". The chain has missing links: the amount, the form, the person and the length of use. A published trial answers a question about its own capsule, its own dose and its own volunteers.
What should you ask before you buy?
Ask for the amount, the lot's lab report and the maker's name, and ask your pharmacist about your own medicines.
- What is the milligram amount of this line in my lot?
- Is there a certificate of analysis I can read, and who issued it?
- Is the facility named anywhere, or only called FDA registered?
- Does this fit with the medicines I take now?
Contact details sit on the contact page. Pharmacists check interactions for free in most pharmacies, and it takes a few minutes 11. Our testing and quality page shows which proofs the brand shows and which it does not.
If you decide to try the product anyway, write down the start date, take the label dose, and keep your home blood-pressure log, as described on the home reading page. That log helps your clinician more than any capsule can.
What are the safety points?
Arginine can lower blood pressure further when taken with blood-pressure medicines, raise potassium with certain diuretics, and is not advised after a recent heart attack.
Mayo Clinic, MSK and NCCIH raise these points 12. Stomach upset, bloating and diarrhoea are the common side effects. Report a bad reaction to FDA MedWatch 12. Chest pain or stroke signs mean 911 1314. Read the side effects page.
FAQ01
Melonex questions people ask
What is L-arginine HCl?
It is arginine bound to hydrochloric acid. The salt dissolves well and is a common form of arginine in supplements.
How much arginine HCl is in Melonex?
At most 167 mg of the 500 mg blend, by label order. The real amount is not printed.
Is arginine HCl different from other arginine?
The arginine is the same. The salt part changes the weight and how the powder dissolves.
Does arginine lower blood pressure?
Some pooled trials at gram doses found small drops, and others were mixed. This site does not claim Melonex lowers blood pressure.
Can arginine be unsafe?
Yes, for some people. It is not advised after a recent heart attack, and it can interact with blood-pressure medicines, nitrates, blood thinners and diabetes medicines.
Where do I report a bad reaction?
Report it to FDA MedWatch and tell the order desk. If you have chest pain or stroke signs, call 911 first.
Who wrote this02
Written and reviewed by
Pages built from the label, the sales page and linked NIH, FDA, CDC, FTC and peer-reviewed sources.
Last updated . Read our editorial standards and how we check reviews. This website is the information site for a USA Authorized Melonex Retailer. It is not the manufacturer or the distributor named on the label. We earn money when you buy through our order links.
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