Medication Summary
Treatment of phenytoin toxicity is primarily focused on limiting the systemic burden of phenytoin by gastrointestinal decontamination and administration of benzodiazepines to manage any seizures that may occur.
GI decontaminant
Class Summary
Multiple-dose activated charcoal is thought to enhance the elimination of phenytoin that was administered orally or intravenously.
Activated charcoal (Liqui-Char)
Preferred GI decontamination method when decontamination is desired. It may be administered with a cathartic (eg, 70% sorbitol), except in young pediatric patients in whom electrolyte disturbances may be of concern. Limited benefit if administered greater than 1 h after ingestion.
Benzodiazepines
Class Summary
Used for seizure control, although seizures in the presence of toxic levels of phenytoin are rare.
Lorazepam (Ativan)
DOC for drug-induced seizures. Longer duration of action compared to the other agents.
Midazolam (Versed)
IV/IM formulation with short duration of sedation. Used as alternative in termination of refractory status epilepticus. Because water soluble, takes approximately 3 times longer than diazepam to peak EEG effects. Thus, clinician must wait 2-3 min to fully evaluate sedative effects before initiating procedure or repeating dose.
Diazepam (Valium)
Depresses all levels of CNS (eg, limbic and reticular formation), possibly by increasing activity of GABA. Commonly available, also useful for treatment of seizures or agitation.