Arginine is a conditionally-essential amino acid. The body is normally able to synthesize a limited amount arginine; the rest must come from diet or supplements. Arginine has many health benefits and is a popular supplement both by itself and in other formulas. Health Benefits of Arginine By far, most of the health benefits attributed to arginine are due to its key role in nitric oxide (NO) production, which dilates bloods vessels and improves blood flow. This may benefit heart health and circulation in general. High doses of arginine may stimulate the secretion of growth hormone. Arginine, along with glycine and methionine, is also used to produce creatine. Additionally, Research shows that arginine may promote wound repair, may help decrease the severity or incidence of migraine headaches, and may help improve some types of erectile dysfunction. Using Arginine: Use arginine products as directed. Side-effects and Cautions: May occur with high doses of 15 grams or more, and include nausea, abdominal cramping and diarrhea. Sensitive individuals may experience side effects at lower doses. Do not use arginine supplements if you suffer from argininemia. Consult your physician before using arginine if you have any medical conditions, or are taking any of the following medications: nitroglycerin, Viagra, cyclosporine, ibuprofen, organic nitrates, or the herbal supplement yohimbe. High doses of arginine may cause herpes or cold sore outbreaks in prone individuals.