Source Naturals L-Phenylalanine, Powder, 100 Grams Go to amazon.com Related posts Expert choice for dl phenylalanine powder FeatureAn essential amino acidFirst converted to tyrosine, which beomes L-dopa, which coverts to norepinephrineVegetarian and hypoallergenic friendly DescriptionAn essential amino acid;First converted to tyrosine, which beomes L-dopa, which coverts to norepinephrine;Vegetarian and hypoallergenic friendly