Neonatal Seizure Drug Calculator

NEONATAL SEIZURES DRUGS

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Drug Concentration Dose Volume Notes
Fosphenytoin IV
(20 mg PE/kg) 		5 mg PE/mL
Dilute 1 mL (PE 50 mg) with 9 mL 0.9% NaCl for a final concentration of PE 5 mg/mL. Give over 10-30 min (max rate: 3 mg PE/kg/min).
Dosed as PHENYTOIN equivalents (PE) 75 mg/mL fosphenytoin = 50 mg PE/mL
MAX 1 g PE
Fosphenytoin IV
(10 mg PE/kg) 		5 mg PE/mL
Dilute 1 mL (PE 50 mg) with 9 mL 0.9% NaCl for a final concentration of PE 5 mg/mL. Give over 10-30 min (max rate: 3 mg PE/kg/min).
Dosed as PHENYTOIN equivalents (PE) 75 mg/mL fosphenytoin = 50 mg PE/mL
MAX 1 g PE
Levetiracetam IV
(60 mg/kg) 		20 mg/mL
Dilute 4 mL (400 mg) with 16 mL of 0.9% NaCl for a final concentration of 20 mg/mL. Give over 15 minutes.
Lorazepam IV
(0.1 mg/kg) 		0.4 mg/mL
Dilute 1 mL (4 mg) with 9 mL of 0.9% NaCl for a final concentration of 0.4 mg/mL. Give over 3 - 5 mins.
Lorazepam Rectal
(0.1 mg/kg) 		0.4 mg/mL
Dilute 1 mL (4 mg) with 9 mL of 0.9% NaCl for a final concentration of 0.4 mg/mL.
Midazolam IV
(150 mcg/kg) 		1000 mcg/mL
Give undiluted over 5 min
Caution: 2 concentrations available.
Phenobarbital IV
(20 mg/kg) 		5 mg/mL
Dilute 1 mL (30 mg) with 5 mL of 0.9% NaCl for a final concentration of 5 mg/mL. Give over 20 min.
Phenobarbital IV
(10 mg/kg) 		5 mg/mL
Dilute 1 mL (30 mg) with 5 mL of 0.9% NaCl for a final concentration of 5 mg/mL. Give over 10 min.
Pyridoxine IV 100 mg/mL
Standard dose: 0.5-1 mL (50-100 mg). Give undiluted over 2 min.
Revised March 2024
References:
  • Slaughter et al. Pharmacological treatment of neonatal seizures: A systematic review. J Child Neurol 2013; 28(3): 351-64
  • Sharpe et al. Levetiracetam versus Phenobarbital for Neonatal Seizures: A Randomized Controlled Trial. Pediatrics June 2020, 45 (6) e20193182
  • Han JY, Moon CJ, Youn YA, Sung IK, Lee IG. Efficacy of levetiracetam for neonatal seizures in preterm infants. BMC Pediatr. 2018;18(1):131. Published 2018 Apr 10. doi:10.1186/s12887-018-1103-1

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