Arginine is a conditionally essential amino acid. Your body uses it to make nitric oxide, a molecule that relaxes blood vessels and helps blood flow move freely through the body.
Many people take arginine to improve workout recovery and exercise performance. Better blood flow means muscles get more oxygen and nutrients during activity. For heart health, it supports normal blood pressure and keeps arteries flexible.
Take arginine on an empty stomach, often 30 to 60 minutes before a workout or at bedtime. Forms include L-arginine, L-arginine HCl, and hydrochloride salts.
Key cautions: Arginine can interact with blood pressure drugs and blood thinners. It may trigger herpes simplex virus outbreaks. Do not use if you have an arginine allergy.