First Things First (assess & treat for the following)

Phenytoin

• Airway management
• ABCs of resuscitation
• Toxicity can be caused by propylene glycol as a diluent in IV formulation, or by phenytoin itself.
• Propylene glycol causes myocardial depression and cardiac arrest.
• Mild to moderate phenytoin intoxication
  • Nystagmus
  • Ataxia
  • Dysarthria
  • Nausea/vomiting
  • Diplopia
  • Hyperglycemia
  • Agitation
• Severe phenytoin intoxication
  • Stupor/coma
  • Respiratory arrest
  • Seizures have been reported; however, this should prompt the investigation into other causes.

Carbamazepine

• Airway management
• ABCs of resuscitation
• Toxicity effects from:
  • CNS depression
  • Anticholinergic effects
  • Cerebellar-vestibular brainstem function
• Mild to moderate overdose
  • Ataxia
  • Nystagmus
  • Ophthalmoplegia
  • Dyskinesia
  • Mydriasis
  • Sinus tachycardia
• Severe overdose
  • Myoclonus
  • Seizures
  • Hyperthermia
  • Coma
  • Respiratory arrest
  • Atrioventricular block
  • QRS widening
  • QT prolongation

Lamotrigine

• Airway management
• ABCs of resuscitation
• Clinical manifestations of overdose
  • Lethargy
  • Dizziness
  • Ataxia
  • Stupor
  • Nystagmus
  • Hypertonia
  • Seizures
  • QRS prolongation
  • Nausea/vomiting
  • Hypokalemia

Topiramate

• Airway management
• ABCs of resuscitation
• Manifestations of overdose:
  • CNS depression
  • Confusion
  • Slurred speech
  • Ataxia
  • Weakness
  • Tremor
  • Clonus
  • Seizures

Gabapentin

• Airway management
• ABCs of resuscitation
• Manifestations of overdose
  • CNS depression
  • Dizziness
  • Ataxia
  • Tremor
  • Slurred speech
  • Diplopia
  • Tachycardia
  • Hypotension or hypertension
  • Diarrhea