SupplementEmergingAmino Acid
L-Arginine
Half-life
~30-120 minutes
What is L-Arginine?
Conditionally essential amino acid that serves as nitric oxide (NO) substrate. Improves vascular function.
How L-Arginine works
Substrate for nitric oxide synthase (NOS) — produces nitric oxide which increases vasodilation, blood pressure reduction, and muscle glucose uptake.
Benefits & uses
- NO/blood flow support (limited orally)
- May support circulation
Common uses: Nitric oxide support, vasodilation, blood flow, endurance, erectile function.
Muscle
L-Arginine dosage
- Typical dose
- 3–6 g (limited by absorption)
L-Arginine half-life
~30-120 minutes (highly variable by form)
L-Arginine side effects
- GI upset on empty stomach
- May worsen cold sore outbreaks (HSV activation — high arginine/lysine ratio)
- Borderline efficacy in many studies vs. citrulline
- GI upset at higher doses
Track L-Arginine in Protokol.
Log doses, model half-lives, check interactions, and line it all up against your bloodwork. Free on iPhone and Android.
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