What is the treatment for lithium overdose?

Treatment of Lithium Overdose

The treatment of lithium toxicity requires immediate intervention with supportive care, discontinuation of lithium, fluid resuscitation, and hemodialysis in severe cases, as there is no specific antidote for lithium poisoning. 1

Assessment and Initial Management

• Lithium toxicity should be suspected in patients presenting with neurological symptoms (tremor, confusion, ataxia), gastrointestinal symptoms (nausea, diarrhea), or polyuria-polydipsia, especially in those taking lithium medication 2

• Determine the pattern of toxicity, which influences treatment approach 3:

  • Acute: single large ingestion in lithium-naïve patients
  • Acute-on-chronic: overdose in patients on maintenance therapy
  • Chronic: most common, usually unintentional accumulation due to impaired elimination

• Obtain serum lithium levels immediately, recognizing that levels above 1.5 mEq/L indicate toxicity, with levels ≥3.5 mEq/L considered potentially lethal 4

Treatment Algorithm

Step 1: Immediate Interventions

• Discontinue lithium medication immediately 1
• Perform gastric lavage if acute ingestion occurred recently (within 1-2 hours) 1
• Initiate IV fluid resuscitation to correct fluid and electrolyte imbalances 1
• Monitor vital signs with particular attention to cardiac status, as bradycardia and heart blocks may occur 5

Step 2: Supportive Care

• Maintain adequate hydration to enhance lithium excretion 1
• Consider administering osmotic diuretics (mannitol) or aminophylline to increase lithium excretion 1
• Provide respiratory support as needed with regular monitoring of respiratory function 1
• Monitor neurological status closely, as CNS toxicity is the primary concern 3

Step 3: Hemodialysis Decision

• Hemodialysis is indicated in the following situations 3, 6:

  • Severe neurological symptoms (seizures, altered consciousness)
  • Serum lithium levels ≥3.5 mEq/L, particularly in chronic toxicity
  • Significant renal impairment limiting lithium excretion
  • Hemodynamic instability or cardiac complications
  • Persistent severe symptoms despite supportive care

• Note that patients with acute lithium toxicity may have milder symptoms despite high serum levels and might not require hemodialysis, while chronic toxicity patients often have more severe symptoms at lower levels 4

Special Considerations

• Cardiac monitoring is essential as cardiac complications occur in approximately 5.7% of hospitalized lithium overdose cases, with bradycardia being the most common 7
• Patients with chronic lithium toxicity are at higher risk for severe symptoms and may require more aggressive intervention than those with acute toxicity 4
• Persistent neurological deficits, particularly cerebellar damage, can occur following severe lithium toxicity 3
• Regular follow-up is necessary after recovery to assess for persistent neurological sequelae 3

Prevention of Recurrence

• Regular monitoring of serum lithium concentrations is recommended during maintenance therapy 2
• Temporarily suspend lithium during intercurrent illnesses, planned IV radiocontrast administration, or prior to major surgery 2
• Educate patients and families about early symptoms of lithium toxicity and the importance of seeking immediate medical attention 1