What is the management of lithium toxicity?

Management of Lithium Toxicity

The management of lithium toxicity requires immediate discontinuation of lithium, supportive care, and in severe cases, hemodialysis to rapidly eliminate lithium from the body. 1

Assessment and Classification

Lithium toxicity is classified based on severity:

• Mild toxicity: Serum lithium levels slightly above therapeutic range
• Moderate toxicity: Higher levels with more pronounced symptoms
• Severe toxicity: Very high levels (>2.5 mmol/L) with life-threatening manifestations

Clinical Manifestations

• Neurological: Tremor, ataxia, confusion, lethargy, seizures, coma
• Gastrointestinal: Nausea, vomiting, diarrhea
• Cardiovascular: ECG changes, hypotension
• Renal: Polyuria, polydipsia, renal dysfunction

Management Algorithm

Step 1: Initial Assessment and Stabilization

• Immediately discontinue lithium
• Assess airway, breathing, circulation
• Obtain serum lithium level, electrolytes, renal function tests
• Monitor vital signs and neurological status

Step 2: Decontamination (for acute ingestions)

• Gastric lavage if recent ingestion (within 1-2 hours) 1
• Activated charcoal is NOT effective for lithium absorption 2

Step 3: Supportive Care

• Correct fluid and electrolyte imbalances 1
• Maintain high-normal sodium levels to reduce intracellular lithium 3
• Monitor and support respiratory function 1
• Monitor cardiac function with continuous ECG

Step 4: Enhanced Elimination

Based on severity:

• Mild toxicity (minimal symptoms, levels <1.5 mmol/L):

  • Discontinuation of lithium
  • IV fluids to enhance renal excretion
  • Close monitoring

• Moderate toxicity (significant symptoms, levels 1.5-2.5 mmol/L):

  • Aggressive IV hydration
  • Consider hemodialysis if renal function is impaired or symptoms are severe

• Severe toxicity (levels >2.5 mmol/L or life-threatening symptoms):

  • Immediate hemodialysis 1, 4
  • Hemodialysis is more effective than peritoneal dialysis 3
  • Prolonged intermittent renal replacement therapy (PIRRT) may be as effective as intermittent hemodialysis 5

Special Considerations

Rebound Phenomenon

• Monitor for rebound increases in serum lithium levels after hemodialysis due to redistribution from tissues
• Repeated dialysis sessions may be necessary 5

Chronic vs. Acute Toxicity

• Chronic toxicity often presents with more severe neurological symptoms despite lower serum levels
• Lower threshold for hemodialysis in chronic toxicity with neurological symptoms

Risk Factors for Toxicity

• Renal impairment
• Dehydration
• Sodium depletion
• Drug interactions (NSAIDs, diuretics, ACE inhibitors)
• Advanced age

Prevention of Recurrence

• Regular monitoring of lithium levels (therapeutic range: 0.6-0.8 mmol/L) 6
• Monitor renal function every 3-6 months 2, 6
• Patient education about early symptoms of toxicity 1
• Avoid medications that interact with lithium
• Maintain adequate hydration and stable sodium intake

Follow-up

• Assess for permanent neurological sequelae
• Re-evaluate need for lithium therapy
• If lithium is restarted, use lower doses with more frequent monitoring
• Consider alternative mood stabilizers if risk of recurrent toxicity is high

Remember that lithium has a narrow therapeutic window, and toxic levels are close to therapeutic levels, making careful monitoring essential 1.