Amino L-Tyrosine 475 mg by Seroyal Genestra is a dietary supplement that provides the body with an amino acid that cannot be manufactured internally. This direct source of tyrosine acts as a support for the brain by aiding in neurotransmitter production. It is also used to help with mood swings and the functionality of the thyroid. pituitary and adrenal glands. This further aids the body in preventing memory loss. reducing fatigue and increasing focus.