This Product has not been evaluated by the Food and Drug Administration. They are not intended to Diagnose Treat Cure or prevent any disease. While we work to ensure that product information is correct on occasion manufacturers may alter their ingredient lists. Tyrosine is a conditionally indispensable amino acid required for the production of the neurotransmitters dopamine adrenaline and noradrenaline as well as for the skin pigment melanin. Noradrenaline (norepinephrine) and adrenaline (epinephrine) are the main actors in the body's response to acute stress and along with dopamine help to support a positive mood and mental alertness. In addition tyrosine is especially critical for the normal function of the thyroid gland.