Main content Phenylketonuria (PKU) Test

    Phenylketonuria (PKU) Test



    What Affects the Test

    Reasons your baby may not be able to have the test or why the results may not be helpful include:

    • Your baby was born early (premature). A baby who weighs less than 5 lb (2.3 kg) may have high levels of phenylalanine but not have phenylketonuria (PKU).
    • Your baby has been drinking milk for less than 24 hours. Best results occur after your baby has been breast-feeding or drinking formula for 2 full days.
    • Your baby is vomiting or refusing to eat. If the PKU test is done before your baby has eaten for 2 days, the results may not be correct.
    • Your baby is getting Reference antibiotics Opens New Window.


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