Bupropion toxicity

Background

• Bupropion is a norepinephrine/dopamine reuptake inhibitor used for depression, ADHD, and smoking cessation
• Toxicity occurs with ingestion of >450mg/d

Clinical Features

• Agitation
• Dizziness
• Tremor
• Nausea/vomiting
• Drowsiness/lethargy
• Tachycardia
• Seizure
  • May develop in isolation from other symptoms
  • Develops within first 1-4hr for regular-release, up to 8hr for delayed release forms
• Hypotension and cardiogenic Shock

Differential Diagnosis

Seizure

• Epileptic seizure
  • First-time seizure
  • Seizure with known seizure disorder
  • Status epilepticus
  • Temporal lobe epilepsy
  • Non-compliance with anti-epileptic medications
  • Hyponatremia
  • INH toxicity
• Non-epileptic seizure
  • Meningitis
  • Encephalitis
  • Brain abscess
  • Intracranial hemorrhage
  • Alcohol withdrawal
  • Benzodiazepine withdrawal
  • Barbiturate withdrawal
  • Baclofen withdrawal
  • Metabolic abnormalities: hyponatremia, hypernatremia, hypocalcemia, hypomagnesemia, hypoglycemia, hyperglycemia, hepatic failure, uremia
  • Eclampsia
  • Neurocysticercosis
  • Posterior reversible encephalopathy syndrome
  • Impact seizure (head trauma)
  • Acute hydrocephalus
  • Arteriovenous malformation
  • Seizure with VP shunt
  • Toxic ingestion (amphetamines, anticholinergics, cocaine, INH, organophosphates, TCA, salicylates, lithium, phenothiazines, bupropion, camphor, clozapine, cyclosporine, fluoroquinolones, imipenem, lead, lidocaine, metronidazole, synthetic cannabinoids, theophylline, Starfruit)
  • Psychogenic nonepileptic seizure (pseudoseizure)
• Intracranial mass
• Syncope
• Hyperventilation syndrome
• Migraine headache
• Movement disorders
• Narcolepsy/cataplexy
• Post-hypoxic myoclonus (Status myoclonicus)

Evaluation

• CBC, CMP
• ECG to eval for QRS and QT prolongation

Management

• Activated charcoal or gastric emptying are not indicated
  • Consider whole-bowel irrigation for sustained-release formulations
• Seizure Treatment
  • Benzos are 1st line
  • Barbiturates are 2nd line
• Early vasopressor and ionotropic agents for hemodynamic instability (Bupropion depresses myocardial contractility)
• Sodium bicarbonate if QRS prolongation
• Intralipid for refractory cases

Disposition

• Consider discharge if asymptomatic after 8hr for regular-release ingestions

See Also

• Bupropion