title: Acetaminophen elimination kinetics in neonates, children, and adults.
abstract: The elimination of acetaminophen (APAP) following an oral dose of 10 mg/kg in newborn infants, children, and adults was compared. Urinary excretion of unchanged APAP, APAP-sulfate, and APAP-glucuronide was complete within 30 hr at all ages. Higher percentages of the dose were excreted in the urine as APAP-sulfate in neonates (0-2 days old) and children (3-9 yr old) than in 12-yr old children and adults. A pharmacokinetic analysis indicated that the higher rate of APAP-sulfate formation in younger age groups apparently compensated for a deficiency in glucuronide formation. No dramatic age-related differences in the overall elimination rate constant for APAP were observed despite the quantitative changes in the metabolic pathways during early childhood.
mesh_terms: D000082:Acetaminophen / Q000378:metabolism* / Q000652:urine; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D005965:Glucuronates / Q000652:urine; D006207:Half-Life; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007700:Kinetics; D008297:Male; D008954:Models, Biological; D013431:Sulfates / Q000652:urine
chemical_list: D005965:Glucuronates; D013431:Sulfates; D000082:Acetaminophen