L-arginine is an amino acid that is vital for the body to produce proteins. It is obtained from natural diet of food such as dairy products, fish, red meat, nuts and poultry. However, there are over-the-counter L-arginine supplements produced in laboratory for people with L-arginine deficiency.

L-arginine is considered a medical breakthrough because of its importance in treating more than a handful of diseases especially high blood pressure, high cholesterol, erectile dysfunction, heart failure, stroke and etc. As L-arginine is a precursor of Nitric Oxide which is important to widening of blood vessels and relaxation of cells muscles, making it a crucial vector in reducing risk of heart attack, improving blood circulation and boosting the immune system, many consider it as a life-saving medication. It is even used to improve recovery after surgery by reducing the recovery time.

However, as with any other drugs it is important to identify with the benefits as well as the side effects it might produce. With L-arginine which is mostly safe for most people, there are few side effects such as abdominal pain, bloating, diarrhea, gout, low blood pressure and etc that might possible affect some minority number of people. Patient with asthma, low blood pressure and had a recent heart attack should take caution too.