DOCTORS BEST: L Tryptophan With Tryptopure 500Mg, 90 vc

L-Tryptophan is an essential amino acid (protein building block) in human nutrition that helps promote healthy sleep. Essential amino acids are not synthesized by the body and must be obtained in the diet. Doctor's Best L-Tryptophan with TryptoPure® is manufactured and tested for purity according to the Japanese Pharmacopeia (JP) and the United States Pharmacopeia (USP) standards.