Mega Arginine 1300 mg of L-arginine hydrochloride in one mega capsule. L-arginine is a conditionally essential amino acid that is produced in the body and also functions as a precursor to nitric oxide (NO), among other functions. The nature of conditionally essential amino acids is due to the fact that the body cannot produce them in sufficient quantities under certain conditions, and therefore they must be introduced into the body mainly through a varied and balanced diet. L-arginine comes mainly from plant and animal sources, but a varied and balanced diet can be supplemented with a product in capsule form, such as Mega Arginine. For women and men. Not just for athletes. For those looking for an easy-to-dosage capsule product containing L-arginine. For those who prefer blister packaging (for 120 capsules).