Other name(s):

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

Unsubstantiated claims

There may be benefits that have not yet been proven through research.

Citrulline is a nonessential amino acid. It 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. It may reduce neutrophilia. It may also improve symptoms in people with sickle cell disease. Further research is needed to determine if citrulline is helpful in these conditions.

Recommended intake

Amino acids (AAs) can be taken as single AAs or in AA combinations. They also come as part of multivitamins, proteins, and food supplements. The forms include tablets, fluids, and powders.

If you eat 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 lessen how well your metabolism works. 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 single amino acids for long periods of time.

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