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Dilantin Toxicity

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Dilantin Toxicity, Phenytoin Toxicity

  • See Also
  1. Phenytoin
  2. Fetal Hydantoin Syndrome
  • Signs
  1. Phenytoin level 20 to 30 mcg/ml
    1. Nystagmus on lateral gaze
    2. Smooth Extraocular Movements lost
    3. Sedation
  2. Phenytoin level >30 mcg/ml
    1. Vertical Nystagmus
    2. Diplopia
    3. Ataxia or lurching gait
    4. Coarse extremity Tremor
    5. Slurred speech
    6. Altered Level of Consciousness
  3. Phenytoin Level >95 mcg/ml
    1. Lethal (deaths have occurred as low as 50 mcg/ml)
  • Differential Diagnosis
  1. Posterior fossa tumor
  2. Acute viral cerebellitis
  3. Guillain-Barre Syndrome
  4. Botulism
  5. Anxiety Disorder
  • Labs
  • Serial levels
  1. Serum free Phenytoin
  2. Serum Glucose
  3. Serum Creatinine
  4. Urinalysis
  5. Electrocardiogram
  6. Liver Function Tests
  • Management
  1. Manage Hypotension
  2. Gastric Decontamination
  3. Treat complete Heart Block
    1. Atropine
    2. Pacemaker
  4. Treat Seizures
    1. Diazepam 0.1 to 0.3 mg/kg IV to 20 mg/dose
    2. May repeat Diazepam dosing in 20 minutes
  • References
  1. Ellenhorn (1997) Medical Toxicology, p. 605-8
  2. Katzung (1989) Pharmacology, p. 289-91