Theophylline metabolism during the first month of life and development.
The metabolic pathway of theophylline (T) was studied in 12 newborns, one young infant, six children, and three adult volunteers. T was injected IV, and blood and urine samples were assayed for T, caffeine (C), and their metabolites by a high-pressure liquid chromatography technique. We confirmed the methylation of T to C in newborn infants but not in older subjects. Demethylation of T to 3-methylxanthine was found in the young infant, in children, and in adults, but not in newborns. The major products excreted by neonates were T, 1-methyluric acid, and 1,3-dimethyluric acid. Children excreted a larger fraction of methyluric acids than adults. Renal and body clearance of T and C are reported and discussed in relation to the age.
D000328:Adult; D002110:Caffeine / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D007668:Kidney / Q000378:metabolism; D008297:Male; D013806:Theophylline / Q000378:metabolism*; D014970:Xanthines / Q000378:metabolism
D014970:Xanthines; C008514:methylxanthine; D002110:Caffeine; D013806:Theophylline