329 ONCE VERSUS TWICE DAILY DOSING OF CEFTAZIDIME IN THE PRETERM INFANT

Ceftazidime (CAZ) pharmacokinetics were studied on day 3 of life in 28 preterm infants who were randomized at birth to receive once or twice daily 25 mg/kg CAZ. Thirteen infants were treated once daily, 15 infants twice daily. Blood samples were collected from an arterial catheter at 0, 0.5, 1, 2, 4, 8, 12h after the CAZ dose in both groups and an additional sample at 24h in the once daily group and analyzed by HPLC-assay. The results were (mean±SD):Conclusions. 1. Twice daily dosing of 25 mg/kg CAZ results in high serum trough levels of CAZ. 2. Dosage reduction from twice to once daily results in a significant decrease of serum trough levels of CAZ to more desired levels. 3. The frequency of CAZ administration may be adjusted after the efficacy of once daily 25 mg/kg CAZ has been studied.