Clinical pharmacology of lorazepam in infants and children

Abstract

Lorazepam is a benzodiazepine has antiepileptic activity; it may be administered intravenously, intramuscularly, orally, by intranasal or buccal application and following oral dosing it is well absorbed. In infants, the initial intravenous dose of lorazepam is 100 µg/kg and in children the initial oral and intravenous dose is 50 to 100 µg/kg and the dose varies according to the child age. Lorazepam has been found efficacy and safe in infants and children but it may induce adverse-effects. Lorazepam is a racemate and the R and S enantiomers are conjugated with glucuronic acid in human liver microsomes and the respective Km and Vmax values are 29+8.9 and 36+10 µM and 7.4+1.9 and 10+3.8 pmol/min*mg. Lorazepam interacts with drugs and the interaction may affect the activity or metabolism of lorazepam. The pharmacokinetics of lorazepam have been studied in infants and children and in diseased children. In infants and children the elimination half-life is about 15 hours and it is about 24 hours and about 37 hours in children with severe malaria and convulsions following intravenous and intramuscular administration, respectively. The treatment and trials with lorazepam have been studied in infants and children. Lorazepam freely crosses the human placenta and poorly migrates into the breast-milk. The aim of this study is to review the published data on lorazepam dosing, efficacy and safety, adverse-effects, metabolism, interaction with drugs, pharmacokinetics, treatment and trials in infants and children and the lorazepam transfer across the human placenta and migration into the breast-milk.