Impact of ontogeny on linezolid disposition in neonates and infants.

The impact of age on linezolid disposition during the first few months of life has not been previously investigated. We characterized linezolid pharmacokinetics after a single, 10.0-mg/kg intravenous dose in 42 infants stratified as follows: group 1 (n = 9), gestational age <34 weeks and postnatal age <8 days; group 2 (n = 7), gestational age <34 weeks and postnatal age 8 days to 12 weeks; group 3 (n = 11), gestational age >or=34 weeks and postnatal age <8 days; and group 4 (n = 15), gestational age >or=34 weeks and postnatal age 8 days to 12 weeks.