L-Arginine and L-Citrulline
L-Citrulline converts to arginine in the kidneys far more efficiently than oral arginine; the two share the same nitric oxide pathway.
L-Arginine
The nitric oxide precursor for blood flow and cardiovascular health.
L-Citrulline
A superior nitric oxide booster that outperforms arginine for pumps and endurance.
Great to combine
These two are frequently stacked together; they complement each other and are commonly taken at the same time.
How to take them
L-Arginine
- Dose
- 3–6 g per day for cardiovascular/ED benefit; 6–10 g pre-workout for performance
- Timing
- 30–60 minutes before exercise for performance; spread throughout the day for cardiovascular goals
L-Citrulline
- Dose
- 6–8 g citrulline malate (2:1) or 3–4 g pure L-Citrulline, 30–60 min pre-workout
- Timing
- 30–60 minutes before exercise
Buying L-Arginine and L-Citrulline?
Choose third-party-tested brands in the forms we recommend on each supplement's page.
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Frequently asked
Can you take L-Arginine and L-Citrulline together?
Yes, they are commonly taken together. L-Citrulline converts to arginine in the kidneys far more efficiently than oral arginine; the two share the same nitric oxide pathway.
What's the best time to take L-Arginine and L-Citrulline?
Around the same time works well. L-Arginine: 30–60 minutes before exercise for performance; spread throughout the day for cardiovascular goals. L-Citrulline: 30–60 minutes before exercise.
How do L-Arginine and L-Citrulline interact?
Synergy: Work better together than alone. L-Citrulline converts to arginine in the kidneys far more efficiently than oral arginine; the two share the same nitric oxide pathway.
Related pairings
L-Arginine + Magnesium
Magnesium supports vascular smooth muscle relaxation alongside nitric oxide from arginine.
L-Arginine + Vitamin C
Vitamin C protects nitric oxide from oxidative breakdown, extending the vasodilatory effect of arginine.
L-Arginine + Zinc
Zinc is a cofactor for nitric oxide synthase, the enzyme that converts arginine to NO.
Creatine + L-Citrulline
A popular pre-workout pairing: citrulline for blood flow and pumps, creatine for power and strength output.