Classification: barbiturate; anticonvulsant
  • sedative
  • used to treat seizures that fail to respond to phenytoin
  • For Status Epilepticus:
    • Loading Dose: 15 mg/kg IV 
    • Maintenance Dose:  15 mg/kg as daily single dose, or 1.5 mg/kg q 8 h
Administration: IV direct:
  • undiluted OR diluted to 10mL with D5W, NS, RL 
IV Infusion:
in 50-100mL D5W, NS, RL
  • maximum rate of administration 60mg/min
Adverse Effects:
  • respiratory depression
    • laryngospasm, bronchospasm, apnea especially if administered too rapidly
  • hypotension; caution in patients with cardiovascular disease
  • solution is very alkaline; extravasation may produce tissue necrosis and thrombophlebitis
  • intra-arterial injection may cause severe pain with reactions ranging from transient pain to gangrene
  • skin rashes
Drug Interactions:
  • phenobarbital + beta adrenergic blockers (eg. propranolol) = decreased beta blocker effect
  • phenobarbital + haloperidol = decreased haloperidol effect
  • phenobarbital + meperidine = increased meperidine CNS depression (increased production of normeperidine)
  • phenobarbital + theophylline = decreased theophylline effect
Monitoring Therapy:
  • respiratory rate
  • BP
  • HR, ECG
  • arterial blood pressure
  • serum concentrations, therapeutic 65-170 uM/L (pre-dose), toxic >215 uM/L
  • administration site 
CCTC Protocol:
  • May be administered IV direct or by IV infusion by an approved nurse in CCTC.
  • Should be administered via a central line if possible.

Lynne Kelly, Pharmacist, CCTC
Brenda Morgan, Clinical Nurse Specialist, CCTC
Last Update: August 7, 2006

LHSCHealth Professionals

Last Updated March 24, 2009 | © 2007, LHSC, London Ontario Canada