Also known as: PKU.

What is phenylketonuria?

Phenylalanine is an amino acid present in many foods high in protein. Ordinarily, the body produces an enzyme that breaks down this amino acid. But people with phenylketonuria do not produce this enzyme, so phenyalanine can build up in the body to dangerous levels.

What causes phenylketonuria?
Phenylketonuria is caused by a genetic mutation. The disease is an inherited disorder that is passed along from parents to their children.

What are the symptoms of phenylketonuria?
As phenylalanine builds up in the body, it can lead to symptoms such as:
  • Delayed physical development
  • Delayed intellectual development
  • Neurological problems
  • Behavioral problems
  • Skin rashes
  • A small head
  • Hyperactivity
  • And other symptoms

What are phenylketonuria care options?

Individuals with phenylketonuria will have to adhere to a strict diet for life that limits protein intake in order to avoid a dangerous buildup of phenylalanine. A special formula can help provide an adequate supply of protein to individuals with phenylketonuria.

Reviewed by: Parul B Jayakar, MD

This page was last updated on: 7/26/2018 11:17:55 AM

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