Ingredient profile
L-arginine AKG in Melonex: line 2 of the blend
L-arginine AKG is the amino acid L-arginine bound to alpha-ketoglutarate, often sold as AAKG. It is line 2 of the Melonex blend, so one capsule holds at most 250 mg of it, partner included. Arginine is the raw material for nitric oxide. Blood pressure trials used 4 to 24 g a day, and arginine is not for people after a heart attack.
Written by the Melonex label deskUpdated
What it is01
What is L-arginine alpha-ketoglutarate?
L-arginine alpha-ketoglutarate is L-arginine joined to a partner molecule, alpha-ketoglutarate. The Melonex label prints it as "L-Arginine (Alpha-Ketoglutarate dihydrate)".
Gyms and sports shops often sell this form as AAKG. Once the partner comes off, the body handles the arginine the same way as arginine from any other source.
Arginine is a semiessential amino acid. It is found in plant and animal proteins, and eating enough protein supplies it (Health Library, Arginine).
| Name on the label | L-Arginine (Alpha-Ketoglutarate dihydrate) |
|---|---|
| What it is | L-arginine bound to alpha-ketoglutarate (often sold as AAKG) |
| Place on the label | Line 2 of 3 in the 500 mg proprietary blend |
| Amount per capsule | Not listed; line 2 of 3 in the 500 mg blend, so at most 250 mg per capsule |
| Amount used in research | About 4-24 g a day of L-arginine in blood pressure trials |
| Strength of evidence | Small blood pressure drops in pooled trials |
| How it is meant to work | Arginine is what nitric oxide synthase uses to make nitric oxide |
| Main caution | Not for use after a heart attack; may add to blood pressure drugs, nitrates and sildenafil. |
Amount02
How much L-arginine AKG is in a Melonex capsule?
A Melonex capsule holds at most 250 mg of L-arginine AKG. The label lists it second in a 500 mg blend of three, and a second line can never outweigh the first.
With an even split it holds about 167 mg. Arginine AKG and arginine HCl together hold at most 333 mg, since citrulline malate takes at least 167 mg.
| Scenario | 1 capsule | 2 capsules |
|---|---|---|
| Even split | About 167 mg | About 333 mg |
| Most the label order allows | 250 mg | 500 mg |
| Both arginine lines, at most | About 333 mg | About 667 mg |
| Lowest dose in arginine trials | 4 g of arginine a day (Dong 2011, arginine meta-analysis) | |
In the body03
What does arginine do in the body?
Arginine is the starting material that nitric oxide synthase enzymes turn into nitric oxide and citrulline (Cziraki 2020, arginine-NO pathway). Nitric oxide raises cGMP in vessel muscle, which helps the vessel relax.
Arginine you swallow is partly used up before it reaches the blood. That is one reason citrulline, line 1 of Melonex, raised blood arginine more in a dosing study (Schwedhelm 2008, citrulline kinetics).
The wider picture is in nitric oxide basics.
Evidence04
What did arginine trials find for blood pressure?
Arginine trials found a small drop in both numbers at gram doses. Eleven trials with 387 people, at 4 to 24 g a day, lowered pressure by about 5.39/2.66 mm Hg compared with placebo (Dong 2011, arginine meta-analysis).
The median dose in those trials was 9 g a day (Khalaf 2019, arginine and citrulline). Results were similar in trials of 4 weeks or more and in people not taking blood pressure medicine (Dong 2011, arginine meta-analysis).
Mayo Clinic says oral arginine may lower blood pressure in healthy people and in people with mildly raised pressure (Mayo Clinic, L-arginine). Not every source reads the evidence the same way, though. One hospital health library lists the blood pressure and vessel-widening claims for arginine as unsubstantiated (Health Library, Arginine).
Both views agree on one point: the studied amounts are in grams. A Melonex capsule holds a fraction of a gram of this line.
Small drop
About 5.39 systolic and 2.66 diastolic, mm Hg, in pooled trials.
Grams a day
4 to 24 g, with a median of 9 g. Two capsules hold at most 0.5 g of this line.
No Melonex trial
Nobody has tested the capsules, or arginine AKG at these amounts.
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See packsHeart attack05
Why is arginine not for people after a heart attack?
Arginine is not advised after a heart attack because a trial in that group saw more deaths. VINTAGE MI gave 9 g a day for 6 months after a first heart attack. It was stopped early: six people on arginine died, and none on placebo (VINTAGE MI trial, JAMA 2006).
Mayo Clinic says arginine is not recommended after a recent heart attack because it might raise the risk of death (Mayo Clinic, L-arginine).
Do not start Melonex on your own. Show the label to your cardiologist first.
Interactions06
Which medicines interact with arginine?
Arginine interacts with medicines that lower blood pressure, thin the blood, lower blood sugar or hold on to potassium (Mayo Clinic, L-arginine). The risk grows with dose, but the label alone cannot tell you yours.
- Blood pressure drugs, nitrates and sildenafil: pressure may drop too low
- Blood thinners and antiplatelets: bleeding risk may rise
- Diabetes drugs: blood sugar may fall further
- Potassium-sparing diuretics: potassium may climb too high
Bring the bottle to your doctor or pharmacist before you start, and never drop a prescription for a supplement. More in supplements and heart medicines.
Next07
How is arginine AKG different from arginine HCl?
Arginine AKG and arginine HCl differ only in the partner bound to the arginine. AKG uses alpha-ketoglutarate; HCl uses hydrochloride. Melonex lists AKG second and HCl third, so AKG is the larger of the two.
The partner matters for the math. A heavier partner leaves less arginine in each milligram of the line. The label gives no ratio for either form, so we report line weights only.
The label does not say why both are used, and no study has compared them inside Melonex. Read the L-arginine HCl profile for line 3.
FAQ08
Questions about L-arginine AKG
What does AAKG mean on a supplement label?
AAKG is shorthand for arginine alpha-ketoglutarate, the form on line 2 of Melonex. It is arginine bound to alpha-ketoglutarate. Melonex prints the full name, L-Arginine (Alpha-Ketoglutarate dihydrate), rather than the short form. Either way, the label weight includes the partner, not just the arginine.
Does arginine AKG improve workouts or muscle?
The evidence does not support it. One health library says there is no evidence that arginine improves athletic performance (Health Library, Arginine). Melonex is not sold as a sports product, and its arginine AKG line holds at most 250 mg a capsule.
Can arginine raise potassium levels?
Yes, it may. Arginine may raise blood potassium, which can be dangerous (Health Library, Arginine), and it should not be combined with potassium-sparing diuretics (Mayo Clinic, L-arginine). People with kidney disease or on those diuretics should ask a doctor before taking Melonex.
Should I avoid arginine during a cold sore or herpes outbreak?
Yes. A hospital health library says people with an active herpes infection should not use arginine (Health Library, Arginine). Wait until you have talked with your doctor, since Melonex contains two forms of arginine. The citrulline on line 1 also turns into arginine, so it does not avoid the issue.
Is arginine hard on the kidneys?
It can be for some people. Single amino acid supplements may strain the kidneys, according to one health library (Health Library, Arginine). If you have kidney disease, show the Melonex label to your doctor before you start.
How much arginine AKG do two Melonex capsules give?
At most 500 mg, and about 333 mg with an even split. That weight includes the alpha-ketoglutarate partner. Arginine trials started at 4 g a day (Dong 2011, arginine meta-analysis), so two capsules give a small fraction of that.
Do I need extra arginine if I eat enough protein?
Most people do not. Arginine is found in plant and animal proteins, and eating enough protein supplies it (Health Library, Arginine). A supplement adds a little more, but it is not needed to meet a basic requirement.
Who wrote this09
Written and reviewed by
Pages built from the label, the sales page and linked NIH, FDA, AHA, CDC, FTC and peer-reviewed sources.
Last updated . Read our editorial standards and how we check reviews. This website is run by a USA authorized Melonex retailer, not by the manufacturer or the distributor. We earn money when you buy through our order links.
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