SOLARAY L-Phenylalanine 500 mg, 60 VegCaps

What the brand says

L-phenylalanine serves as a building block for the various proteins that are produced in the body. L-phenylalanine can be converted to L-tyrosine (another amino acid) and subsequently to L-dopa, norepinephrine, and epinephrine. L-phenylalanine can also be converted (through a separate pathway) to phenyl ethylamine, a substance that occurs naturally in the brain and elevates one's mood.