Treatment of Lithium Toxicity
Hemodialysis is the most effective treatment for severe lithium toxicity, while mild to moderate toxicity may be managed with supportive care and cessation of lithium. 1
Assessment of Lithium Toxicity
• Lithium toxicity is classified into three grades: mild, moderate, and severe, with treatment approach determined by severity 2 • Toxic levels of lithium are dangerously close to therapeutic levels (therapeutic range: 0.6-1.0 mM) 3 • Serum lithium levels of 1.5-2.0 mM may cause mild and reversible toxic effects on kidney, liver, heart, and glands 3 • Levels >2.0 mM may cause neurological symptoms, including cerebellar dysfunction 3 • Prolonged lithium intoxication >2 mM can cause permanent brain damage 3 • Important: Clinical signs of toxicity may be present even with normal serum lithium levels, particularly in patients with renal impairment 4
Treatment Algorithm
Mild Lithium Toxicity
• Discontinue or reduce lithium dosage 2 • Monitor serum lithium levels until normalized 1 • Ensure adequate hydration and electrolyte balance 5 • Resume treatment at lower dose after 24-48 hours if clinically indicated 1
Moderate to Severe Lithium Toxicity
• Immediate cessation of lithium 1 • Gastric lavage if recent ingestion 1, 5 • Correction of fluid and electrolyte imbalances 1 • Maintain adequate urine output 1 • Consider hemodialysis for:
- Serum lithium levels >2.0 mM 3
- Patients with impaired renal function 5
- Presence of significant neurological symptoms 1
- Deteriorating clinical status despite supportive measures 2
Specific Interventions
• Hemodialysis: Most effective method for rapid elimination of lithium from the body in severe toxicity 1, 2 • Peritoneal dialysis: Less effective alternative for patients with impaired renal function who cannot undergo hemodialysis 5 • Sodium administration: Maintaining high-normal sodium levels may help reduce intracellular lithium concentration 2 • Urea, mannitol, and aminophylline: Can increase lithium excretion 1 • Infection prophylaxis: Essential during treatment of severe toxicity 1 • Regular monitoring: Chest X-rays and respiratory function should be assessed regularly 1
Prevention of Lithium Toxicity
• Regular monitoring of serum lithium concentrations, especially during the acute phase of treatment 6 • Serum concentrations should be determined twice per week during the acute phase until stabilized 6 • Educate patients and families about early symptoms of toxicity 1, 7 • Use conservative dosing and exercise caution when combining lithium with other medications 7 • Be particularly cautious in patients with renal impairment 4 • Temporarily suspend lithium during intercurrent illness, planned IV radiocontrast administration, bowel preparation, or prior to major surgery 6
Common Signs and Symptoms of Lithium Toxicity
• Early/mild: Tremor, nausea, diarrhea, polyuria-polydipsia 6 • Moderate: Confusion, drowsiness, ataxia, coarse tremor 4 • Severe: Semi-coma, coma, seizures, oliguria, cardiovascular collapse 5
Important Considerations
• There is no specific antidote for lithium toxicity 1, 5 • The clinical presentation of toxicity is more important than serum lithium levels alone when determining treatment approach 4 • Chronic lithium intoxication often begins with insidious kidney impairment followed by "prodromal" symptoms 5 • Once moderate severity is reached, decreasing kidney function can create a vicious cycle that accelerates toxicity 5 • Forced diuresis is only effective in patients with unimpaired renal function 5