NOW Foods L-Phenylalanine 500mg, 120 Capsules
L-Phenylalanine is an essential amino acid that can be readily converted into the amino acid tyrosine.  Because tyrosine is necessary for the synthesis of proteins and the production of the neurotransmitters dopamine and norepinephrine, phenylalanine is an extremely important nutrient that must be obtained through the diet or supplementation.*