L-Citrulline
The recycler that keeps MemoHoney's nitric oxide cycle running.
| Amount per capsule | 250 mg* |
|---|---|
| Category | Amino acid |
| Stimulant? | No |
What it is
L-Citrulline is a non-essential amino acid first identified in watermelon, from which it takes its name (citrullus). In supplement form, it's typically used as L-Citrulline HCl or citrulline malate, valued less for its own direct effects and more for what it becomes once inside the body.
How it works
Unlike arginine, citrulline largely bypasses first-pass metabolism in the liver, meaning more of it survives to reach the kidneys, where it's converted into arginine and released into circulation. This makes citrulline an effective way to raise plasma arginine levels indirectly — and, by extension, to sustain nitric oxide production for longer than supplementing arginine alone.
The "recycling" effect
Think of it as a supply chain: arginine converts into nitric oxide and citrulline as byproducts; citrulline then converts back into arginine, which can be used again. This cycle is why pairing L-Arginine with L-Citrulline is common in circulation-focused formulas rather than relying on either ingredient alone.
Metabolic clearance
Some citrulline formulations, including citrulline malate, are also studied in the context of clearing metabolic byproducts associated with fatigue during sustained physical or mental exertion — relevant to that "heavy, foggy" feeling some people describe after a long day.
Safety notes
L-Citrulline is generally well tolerated at typical supplement doses. Because it ultimately raises arginine and nitric oxide activity, the same caution applies as with L-Arginine: check with a doctor first if you take blood pressure medication, blood thinners, or other vasodilators, or if you are pregnant or nursing.