[Monitoring theophylline in premature newborn infants].

In order to defined the PO theophylline dose which produced effective theophylline concentrations between 4-10 micrograms/ml in prematures babies, we analized the theophylline pharmacokinetic of 6 adequate weight for gestational age female prematures, aged 31-34 gestational weeks, to which we administered PO 5 mg/kg of theophylline as the attack dose, following by a PO maintained dose of 2.5 mg/kg/12 h. In steady-state we did the pharmacokinetic studies after the administration of one dose. We found that only maintenance doses of 2.5 mg/kg/12 h produced therapeutic theophylline concentrations. Considering the pharmacokinetic data, we conclude that PO maintenance dose of 3 mg/kg/12 h of theophylline will be necessary to reach effective theophylline concentration.