L-Citrulline
What the evidence shows
Converts to L-arginine in the kidneys more efficiently than taking arginine directly (arginine is heavily metabolized in the gut and liver before it reaches circulation), making citrulline the more bioavailable route to raising nitric oxide production. Small trials in mild ED show real, if modest, benefit — nowhere near PDE5 inhibitor magnitude, but a legitimate adjunct.
How it's thought to work
Converted to arginine via the kidneys, subsequently raising nitric oxide synthase substrate availability and supporting vasodilation.
Typical Dosage
3–6g/day.
Safety Notes
Very well-tolerated, minimal GI upset compared to arginine. Same nitrate/PDE5-inhibitor caution as arginine applies.
Want the full clinical breakdown?
Does L-citrulline help erectile dysfunction? It raises plasma arginine more effectively than L-arginine itself — a clinical trial confirms erection hardness improvement at 1.5g/day in men with mild ED.
Read the full evidence reviewConsidering adding L-Citrulline to your routine?
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