What happens during a PKU screening test?A health care provider will clean your baby's heel with alcohol and poke the heel with a small needle. The provider will collect a few drops of blood and put a bandage on the site.The test should be done no sooner than 24 hours after birth, to ensure the baby has taken in some protein, either from breast milk or formula. This will help ensure the results are accurate. But the test should be done between 24–72 hours after birth to prevent possible PKU complications. If your baby wasn't born in the hospital or if you left the hospital early, be sure to talk to your child's health care provider to schedule a PKU test as soon as possible.
