L-Arginine Safety: Possible Side Effects of Excessive L-Arginine

There are several powerful new drugs that help in preventing and treating chronic health issues. Before moving on to discuss L-arginine its uses and side effects, we need to know what is L-arginine. L-arginine is an amino acid, a chemical building block, obtained from our diet, which is essential for our body to make proteins. L-Arginine is gaining a lot of attention lately for its potential heart benefits. Let us discuss some of the benefits and side effects of excessive L-arginine.

Arginine deficiency is quite rare as it is abundant in many different types of foods such as red meat, poultry, fish, grains, wheat germ, dairy products, nuts, and seeds. However, it is also made in laboratories for making medicines. Our body converts L-arginine into a chemical called nitric oxide. Nitric oxide makes our blood vessels to open wider that leads to an improved blood flow. It also stimulates the release of insulin, the growth hormone and other substances in the body.

Sources of l-arginine

Uses of L-Arginine

L-arginine is responsible for a number of functions in the body including healing wounds, maintaining hormone and immune functions, helping the kidneys in removing the waste products, and dilating and relaxing the arteries. L-arginine is effective for chest pain. It can reduce the symptoms and improve your exercise tolerance. However, it cannot cure the disease itself. It is also effective for treating erectile dysfunction, lowering high blood pressure, preventing inflammation of the digestive tract in premature infants, preventing nitrate tolerance, relieving leg pain associated with poor blood flow, and improving recovery and reducing several infections after surgery.


L-Arginine Side Effects

  • Allergic Reactions: Some people may experience anaphylaxis, a severe allergic reaction, to L-arginine. The severity of allergy increases with the increase in the dosage. Some of the symptoms may include skin rashes, itching, shortness of breath, and swollen eyes. Asthmatic people may be more prone to this reaction.
  • Digestive Problems: L-arginine may increase the levels of stomach acids, especially gastrin. Increase in gastrin levels can cause abdominal pain and nausea. People may also experience issues such as bloating, diarrhea, and cramps.
  • Blood Pressure: Owing to its property as a vasodilator, it may result in low blood pressure. An individual having low blood pressure may also experience dizziness, fainting, and blurred vision.
  • Chemical Imbalance: Being an amino acid, L-arginine can affect chemical and electrolyte balance. It makes our body produce more chloride, potassium, creatinine, and blood urea nitrogen. It may also cause lowering of the levels of sodium and phosphate. Patients suffering from Liver and kidney disorders are more prone to these chemical imbalances.
  • Children: It is probably safe when used orally in appropriate doses in premature infants. However, an overdose of arginine can lead to serious side effects including death in children.
  • Pregnancy and Breastfeeding: A short-term arginine intake during pregnancy is possibly safe when taken orally. However, long-term usage is not exactly known. So, if you are pregnant, stay on the safe side.
  • Methyltransferase Deficiency: It is a genetic disorder when people are unable to convert arginine and similar chemical to creatine. People with this disorder need to use it with caution in order to prevent complication.
  • Herpes: L-arginine may make herpes worse. Some evidence shows that herpes needs L-arginine to multiply.


As mentioned earlier, there are certain foods that contain L-arginine. Therefore, if you are planning to opt for a supplement, you need to consider your diet for a safe dosage. If you are already in a diet that is high in L-arginine, try beginning the supplementation at a low dose in order to determine your body’s reaction. Too much arginine can lead to serious issues. You need to consider the side effects of excessive L-arginine. Also, consult your healthcare provider before taking any supplement.