L-citrulline / citrulline malate

Also known as citrulline, citruline, citrulline malate.

Last reviewed October 9, 2026 · Jump to references

What is L-citrulline / citrulline malate?

In plain words

L-citrulline is an amino acid the body makes naturally; citrulline malate combines it with malate, a substance involved in energy production. The body turns citrulline into arginine, which helps make a signal that relaxes blood vessels. Researchers study these forms for blood flow, exercise performance, and muscle soreness. Findings on exercise benefits are mixed, and some people experience stomach upset.

Technical definition

L-citrulline is a non-proteinogenic amino acid involved in the urea cycle; citrulline malate combines L-citrulline with malate, a citric acid cycle intermediate. L-citrulline is converted primarily in the kidneys to L-arginine, a substrate for nitric oxide synthase, thereby supporting nitric oxide production rather than directly activating a receptor. Both forms are marketed as dietary supplements in the United States, not FDA-approved medicines for treating disease.

Educational information only. This page does not provide medical advice or determine whether a supplement is appropriate for you. Review supplements with a qualified healthcare professional, especially if you take medication, are pregnant, have surgery scheduled, or have a chronic medical condition.

Evidence by use

Each use is rated on its own. There is no single overall effectiveness score.