title: A study of conjugation and drug elimination in the human neonate.
abstract: 1 An investigation has been made of the excretion of alpha-methyldopa, alpha-methyldopa sulphate, lorazepam and lorazepam glucuronide in the urine of neonates. 2 The rate of elimination of both the drugs in the newborn is slow compared with the adult rate, and apparent half-life being 3 to 4 times longer than the reported adult values. 3 The newborn appear able to readily metabolise alpha-methyldopa to alpha-methyldopa sulphate and to slowly conjugate lorazepam with glucuronic acid. alpha-Methyldopa tends to be conjugated to a greater extent and lorazepam to about the same or slightly lesser extent in the newborn than in adults. 4 It is postulated that elimination in the neonate is mainly controlled by the rate of renal excretion in the case of alpha-methyldopa and by the rate of conjugation in the case of lorazepam.
mesh_terms: D014151:Anti-Anxiety Agents / Q000652:urine*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications; D007231:Infant, Newborn; D008140:Lorazepam / Q000031:analogs & derivatives / Q000378:metabolism / Q000652:urine*; D008297:Male; D008431:Maternal-Fetal Exchange; D008750:Methyldopa / Q000378:metabolism* / Q000627:therapeutic use / Q000652:urine; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000188:drug therapy; D013431:Sulfates / Q000652:urine
chemical_list: D014151:Anti-Anxiety Agents; D013431:Sulfates; D008750:Methyldopa; D008140:Lorazepam; C031290:lorazepam glucuronide