Phenylalanine

Phenylalanine (Phe) is a type of amino acid. There are three different forms of penylalanine---L-phenylalanine, D-phenylalanine, and DL-phenylalanine. In humans, different forms of phenylalanine have been proposed to be a possible treatment for depression because of their association with norepinephrine, which affects mood.