Document Type : Short Communication


1 Pediatrician, Neonatal specialist assistant, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

2 Neonatologist, Professor, Neonatal Research Center, Imam Reza Hospital, Faculty of Medicine, Mashhad, University of Medical Sciences, Mashhad, Iran

3 Neonatologist, Assistant professor, Neonatal Research Center, Imam Reza Hospital, Faculty of Medicine, Mashhad, University of Medical Sciences, Mashhad, Iran.

4 Mashhad university of medical science

5 2Neonatal intensive care nurse. Faculty of Nursing and Midwifery, Mashhad University of Medical Science, Mashhad, Iran.

6 Associated Professor of neonatology, Neonatal research center, faculty of medicine, Mashhad University of Medical, Mashhad, Iran



Introduction: Newborns may be treated with phenobarbital for many reasons. Because in each region, depending on different races and genetic factors, different pharmacokinetic conditions govern the drug. It is essential to control blood levels of certain drugs, especially phenobarbital, and maintain these levels during treatment. In this study, we measure the level of phenobarbital in newborns who receive intravenous.
Methods: In this study, venous blood was collected from 50 neonates who received intravenous phenobarbital at a loading dose of 20 mg/kg weight, and at least, three days had passed since the maintenance dose of 5 mg/kg body weight in 24 hours, and sent to the laboratory. Phenobarbital blood levels were measured, and the results were analyzed descriptively.
Results: In this study, the average weight of newborns in two groups was 9.93 ± 2.58 kg. The mean blood concentration of phenobarbital, three days after starting the maintenance dose in the group of infants weighing more than 2.5 kg was 3.33 ± 9.1 micrograms/liter, in the group of infants weighing less than 2 kg. and half a kilogram or LBW was 5.9 ± 9.5 micrograms/liter, and in the group weighing less than 1.5 kg VLBW was 14.4 ± 15.46 micrograms/liter. There was no significant difference between case and control group (p>0.05). Three days after starting the maintenance dose in all three groups, the mean blood phenobarbital concentration was 9.86 ± 0.86 micrograms/liter.
Conclusion: Blood phenobarbital levels in our newborns are below therapeutic levels at day two, so phenobarbital levels should be evaluated.


Main Subjects


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