Understanding Phenylketonuria (PKU)

PhenylKetonUria (fen-­ul­-ke­-toe-­NU-­re-­uh) is an inborn error of metabolism that causes an amino acid known as phenylalanine (fen-­ul-­AL-­uh­-neen), or “Phe,” to build up in the blood because the phenylalanine hydroxylase (PAH) enzyme is either missing or not working properly.

Know more about PKU and how to manage Phe levels

About 1 in 10,000 to 15,000 babies in the United States is born with PKU.1 Newborns are checked for PKU with a simple blood test, making it possible to diagnose and begin treatment at an early stage. If PKU isn’t treated, high or unstable Phe levels can cause serious physical and mental health problems.

Treatment guidelines recommend that treatment begin as early as possible and continue through life.2 By starting early and managing Phe levels for life, most symptoms can be prevented or treated.

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Get additional information and learn how you can manage PKU.

What Is PKU?

Get additional information and learn how you can manage PKU.

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Learn more about what causes PKU and the 3 main types of PKU.

Causes and Types of PKU

Learn more about what causes PKU and the 3 main types of PKU.

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Learn about how Phe can affect the body and the importance of keeping blood Phe levels low.

All About Phe

Learn about how Phe can affect the body and the importance of keeping blood Phe levels low.

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Learn about the signs and symptoms of untreated PKU.

Signs and Symptoms of PKU

Learn about the signs and symptoms of untreated PKU.

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Learn about available treatment options and how you can take control of PKU.

How Is PKU Treated?

Learn about available treatment options and how you can take control of PKU.

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Find answers to your most commonly asked questions about PKU.

Understanding PKU FAQs

Find answers to your most commonly asked questions about PKU.

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References: 1. National Human Genome Research Institute. Learning about phenylketonuria. http://genome.gov/pdf. Updated August 15, 2012. Accessed May 28, 2014. 2. Vockley J, Andersson HC, Antshel KM, et al; for the American College of Medical Genetics and Genomics Therapeutic Committee. Phenylalanine hydroxylase deficiency: diagnosis and management guideline. Genet Med. 2014;16(2):188-200.