F*CK Getting Old

Supplement Database

Citrulline Malate

6 g · Pre-workout

Evidence

3.0/5
Human Studies
30
Animal Studies
15
Clinical Status
Dietary Supplement
Confidence
Moderate
Long-Term Safety
Well-tolerated in performance trials; most studies are short-duration around exercise, not long-term daily use

What this score is: a measure of how much research exists and how far along it is (animal-only vs. human trials, research-stage vs. FDA approved) — not how safe, effective, or worth trying a compound is. A low score usually means “early stage” or “understudied,” not “bad.” A high score doesn’t mean “better” for your goals than a lower-scored one.

This is not my personal rating of the compound, not a recommendation, and not medical advice. It’s a general research synthesis for informational purposes only, not a live literature count. See the linked research and talk to a licensed clinician before making decisions based on it.

Mechanism

Citrulline is converted to arginine in the kidneys, which is then converted to nitric oxide, promoting vasodilation. It is more bioavailable orally than direct arginine supplementation because it bypasses first-pass liver metabolism that breaks down much of an oral arginine dose before it reaches circulation.

Common Protocols

  • 6–8 g of citrulline malate, roughly 30–60 minutes before training

Side Effects

  • Mild GI upset at higher doses
  • Generally well-tolerated

Interactions

  • May have additive blood-pressure-lowering effects with medications for hypertension or erectile dysfunction (e.g. PDE5 inhibitors) — caution combining

Practical Details

Cost
$
Typical Dose
6 g
Storage
Store in a cool, dry place

Research Links

Nitric oxide precursor; pump and endurance support