Diazepam elimination in premature and full term infants, and children.

In recent years a considerable amount of data have been produced on the activity of the microsomal drug metabolizing Systems in the human fetus [10, 16, 17,18, 19, 21, 26, 29, 32]. They all indicate that the various metabolic Systems responsible for drug degradation are already present in the intrauterine life, though their specific activity is in most cases considerably lower than that of adult Standards. "In vitro" data, while certainly necessary, do not provide an exact index of the rate of "in vivo" metabolism and therefore the Information which can be derived is not easily applicable to clinical Problems. In fact drug effects are also determined by other factors, such äs absorption rate, plasma protein binding, tissue distribution and excretion rate. All these factors vary both with age and physiopathological Status [21, 26]. For this reason studies and observations on newborn infants provide further useful Information, which can eventually be applied to everyday practice. Most of the data currently available on drug kinetics and metabolism in the newborn infant concern antibiotic and sulfonamide compounds [8, 11, 23, 24, 26, 27, 28] though some observations have also been carried out with other drugs [13, 14, 21, 22, 30, 31]. In most cases they indicate a slower disposition of the drug äs compared to children. No data on the metabolic disposition of benzodiazepines in the newborn infant have been available up to now, despite the fact that this class of drug is widely administered during Curriculum vitae