Source: Examine.com — Arginine — Blood-flow effects need ~3–6 g; oral arginine is poorly absorbed, so citrulline is generally preferred.
Blood-flow studies use 3–6 g; citrulline raises arginine more reliably, so arginine under ~3 g does little.
An amino acid and nitric-oxide precursor once popular for pumps and blood flow.
Converts to nitric oxide to widen blood vessels — but much is destroyed in digestion, so citrulline (which raises arginine more reliably) is usually the better choice.
Safe; large doses can cause GI upset. Doses under ~3 g (common in T-boosters) do very little.
| Per serving | |
|---|---|
| Typical branded single-ingredient product | $0.42 |
| Bulk powder at the clinical dose (500g, $25.97) | $0.16 |
Buying bulk powder instead of a branded bottle saves about 62% per serving.
Bulk price: $25.97/500g →Educational only — not medical advice. Grades and clinical doses are computed from public labels against sourced research (citations on the main site); prices last verified 2026-07-21. Expensive Powder has no sponsors; bulk links may earn an affiliate commission, which never affects a grade. Talk to a clinician before starting any supplement.