dl-Phenylalanine is a combination of the well-tolerated essential amino acids, d-phenylalanine and l-phenylalanine. Together, these compounds promote mental functioning, support a positive outlook, and relax the musculoskeletal system. l-Phenylalanine is a precursor to tyrosine, which converts to the neurotransmitters norepinephrine, epinephrine, dopamine and tyramine. Tyrosine and its metabolites have been shown to support emotional well-being, memory and learning. d-Phenylalanine may regulate the levels of certain endorphins, thereby calming stressed muscles and joints. By maintaining healthy tyrosine and endorphin levels, dl-phenylalanine nutritionally supports mental acuity and emotional well-being, while relaxing stressed muscles and joints. Each VCapsule Contains dl-phenylalanine (free-form) 500 mg. vitamin C (ascorbyl palmitate) 10 mg.