L-Tyrosine is an amino acid that the body produces from L-Phenylalanine. Tyrosine is needed for the production of thyroxine and melatonin. It has been suggested that the brain cannot produce enough tyrosine from L-Phenylalanine under stress. Use: Improve thyroid function, for stress management, to increase low energy levels, for increased alertness, as an appetite suppressant, and to increase sexual desire. Refer to ‘instructions for use’ for details on dosage for specific conditions.