Other name(s):

a-amino-d-ureido-n-valeric acid

Unsubstantiated claims

Please note that this section reports on claims that have not yet been substantiated through scientific studies.

Citrulline removes ammonia from your body. It may also stimulate the immune system and boost energy levels. Early studies show that citrulline doesn’t help exercise performance. Citrulline may reduce neutrophilia. It may also improve symptoms in people with sickle cell disease.

Recommended intake

Amino acids (AAs) are available as individual AAs or in AA combinations. They also come as part of multi-vitamins, proteins, and food supplements. The forms include tablets, fluids, and powders.

Note that by eating enough protein in your diet, you get all of the amino acids you need.

There are no conditions that increase how much citrulline you need.

Side effects, toxicity, and interaction

Using a single amino acid supplement may lead to negative nitrogen balance. This can decrease how efficient your metabolism is. It can also make your kidneys work harder. In children, taking single amino acid supplements may also cause growth problems.

You should not take high doses of individual amino acids for long periods of time.

Women who are pregnant or breastfeeding should not use citrulline supplements.