Phenylketonuria (PKU) is an inherited disorder that causes the level of phenylalanine (phe) to be too high in the blood. Phenylalanine comes from protein digestion. People with PKU do not have enough of an enzyme called phenylalanine hydroxylase that helps break down phe. https://sanjanacmi.livepositively.com/phenylketonuria-treatment-overview-of-causes-and-symptoms-of-phenylketonuria/new=1