Natural Standard® Patient Monograph, Copyright © 2017 ( All Rights Reserved. Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.


L-arginine was first isolated in 1886, reportedly from the extract of a lupine (Lupinus spp.) seedling. Lupinus is a genus in the legume (Fabaceae) plant family.

Arginine is an amino acid normally made by the body. Arginine is also found in many foods that have protein.

Arginine becomes nitric oxide (a blood vessel-widening agent called a vasodilator) in the body. Early evidence suggests that arginine may help treat medical conditions that improve with increased vasodilation. These conditions include chest pain, atherosclerosis (clogged arteries), heart disease, heart failure, erectile dysfunction, peripheral vascular disease, and headaches from blood vessel swelling).

Arginine also triggers the body to make protein and has been studied for healing wounds, bodybuilding, enhancing sperm production, and preventing tissue wasting in people with critical illnesses. However, caution is warranted. Arginine use was associated with death in some people with heart conditions. Caution is also needed when using arginine to treat pre-eclampsia (high blood pressure in pregnancy).

Arginine hydrochloride has been used to treat metabolic alkalosis. This use should be under the supervision of a qualified healthcare professional.

This evidence-based monograph was prepared by The Natural Standard Research Collaboration