Pharmacology and cerebrospinal fluid penetration of moxalactam in children and dosage recommendations.

The pharmacokinetics and penetration into cerebrospinal fluid (CSF) of moxalactam were evaluated in 20 children with bacterial meningitis. After moxalactam was given iv as a loading dose of 100 mg/kg followed by two doses of 50 mg/kg every 6 hr, the mean serum concentrations were 205 micrograms/ml at the end of the last infusion and 11 micrograms/ml at 6 hr. The beta elimination half-life was 3.6 hr for children younger than nine months of age and 1.7 hr for children older than nine months of age. The mean CSF concentration of moxalactam was 3.8 micrograms/ml (range, 0.9-22.6 micrograms/ml). The mean concentration of moxalactam in CSF was 19.1% (range, 3.1%-97%) that in serum. Bactericidal titers were at least 1:32 in 12 CSF specimens. Concentrations of moxalactam in CSF correlated significantly (P less than 0.001) with concentrations of protein in CSF. Concentrations of moxalactam in CSF were greatly in excess of minimal inhibitory/bactericidal concentrations for Haemophilus influenzae type b. Dosages of moxalactam for the treatment of systemic infections due to H. influenzae type b in children are proposed.