The purpose of this study is to investigate how acetaminophen (APAP) is released into the
urine and blood; to determine how the blood levels of acetaminophen and its breakdown
products affect the preterm infant's health; to decrease adverse drug reactions; and to
collect data on how the genetic make-up or characteristics affect how APAP is handled within
the preterm infant. By taking several blood and urine samples during the study, we will be
able to check the blood levels (called pharmacokinetics) of APAP in preterm babies.