Pure Encapsulations DL-Phenylalanine 180cPure Encapsulations DL Phenylalanine supports brain, memory, muscles, and emotional well being. It is made with hypoallergenic, vegan ingredients and helps promote mental acuity and comfort. DLPA is a dietary supplement that supports mental functioning and emotional well being. It is a combination of D phenylalanine and L phenylalanine which have been shown to support positive outlook, memory, and muscle relaxation.