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Lithium Toxicity
Aka: Lithium Toxicity, Lithium Poisoning, Lithium Intoxication
- See Also
- Lithium
- Mechanism
- Lithium has a narrow therapeutic range
- Lithium concentrates most in CNS and renal tissue
- Risk Factors: Toxicity
- Renal dysfunction (Low Glomerular Filtration Rate)
- Volume depletion (associated with greater Lithium reabsorption)
- Vomiting or Diarrhea
- Acute Heart Failure
- Cirrhosis
- Diuretics
- Medications
- Thiazide Diuretics (e.g. Hydrochlorothiazide, Chlorthalidone)
- ACE Inhibitors
- NSAIDS
- Findings: Gastrointestinal
- Nausea or Vomiting
- Diarrhea
- Findings: Neurologic (late sign in acute toxicity, common in chronic toxicity)
- Listless or sluggish
- Ataxia
- Confusion
- Agitation
- Tremors or Myoclonic Jerks
- Seizures and encephalopathy (severe cases)
- Labs: General
- Complete Blood Count (CBC)
- White Blood Cell Count is commonly increased with Lithium Toxicity
- Serum chemistry (chem8)
- Nephrotoxicity (assoc. with chronic Lithium Toxicity)
- Increased Serum Creatinine, Blood Urea Nitrogen
- Nephrogenic Diabetes Insipidus
- Hyponatremia
- Urine Pregnancy Test
- Thyroid Stimulating Hormone (TSH)
- Hypothyroidism or Hyperthyroidism
- Unknown Ingestion and Altered Level of Consciousness testing
- Acetaminophen Level
- Salicylate Level
- Urine Drug Screen
- Serum Glucose
- Labs: Lithium Level
- Precautions
- Peak levels may not be reached for >12 hours after Overdose of sustained release Lithium
- For a given level, symptoms may be more mild in acute toxicity than in chronic toxicity
- Therapeutic Level: 0.8 to 1.2 mEq/L
- Mild Toxicity: 1.5 to 2.5 mEq/L
- Tremor
- Slurred Speech
- Listlessness
- Moderate Toxicity: 2.5 to 3.5 mEq/L
- Coarse Tremor
- Myoclonic Jerks
- Severe Toxicity: >3.5 mEq/L
- Encephalopathy
- Seizures
- Diagnostics
- Electrocardiogram
- T Wave Flattening
- QTc Prolongation
- Bradycardia
- Differential Diagnosis
- See Altered Level of Consciousness
- See Unknown Ingestion
- Serotonin Syndrome
- Neuroleptic Malignant Syndrome
- Alcohol Withdrawal
- Benzodiazepine Withdrawal
- Closed Head Injury
- Cerebrovascular Accident
- Management: General
- See ABC Management
- Gastric Decontamination (acute toxicity only)
- AVOID Activated Charcoal (no benefit)
- Whole Bowel Irrigation
- Consider in awake asymptomatic patients within 2-4 hours of large Lithium SR ingestion
- Give 500 to 2000 ml Polyethylene glycol via Nasogastric Tube until rectal output clear
- Fluid Resuscitation
- First-line management of Lithium Toxicity
- Isotonic crystalloid (NS or LR)
- Administer IV hydration at twice maintenance for 2-3 Liters of crystalloid
- Rate of replacement should be decreased if Hyponatremia (prevent Central Pontine Myelinolysis)
- Altered Mental Status
- See Altered Level of Consciousness
- See Unknown Ingestion
- Bedside Serum Glucose (and treat Hypoglycemia)
- Consider Naloxone
- Consider Thiamine
- Seizures
- See Status Epilepticus
- Benzodiazepines
- Disposition
- Admit Lithium Toxicity to medical ward (severe toxicity to ICU)
- May discharge when patient is asymptomatic and serum Lithium <1.5 mEq/L
- Management: Hemodialysis Indications
- Serum Lithium Level >5 mEq/L
- Serum Lithium Level >4 mEq/L AND concurrent Serum Creatinine >2.0 mg/dl)
- Serum Lithium Level >2.5 mEq/L AND
- Neurologic symptoms (Seizures, decreased mental status) OR
- Conditions in which flud Resuscitation is limited (e.g. Congestive Heart Failure) OR
- Conditions limiting Lithium excretion (e.g. Renal Failure)
- Serum Lithium Level >1.5 mEq/L AND
- Life threatening complications attributed to Lithium Toxicity
- Increasing serum Lithium levels despite maximal medical therapy with fluid Resuscitation
- Complications: Chronic Lithium Toxicity
- Syndrome of Irreversible Lithium Effectuated Neurotoxicity (SILENT)
- Persistent neurologic and psychiatric effects despite Lithium discontinuation
- Effects may include Extrapyramidal Effects, Dementia, Ataxia, Brainstem or cerebellar dysfunction
- Nephrogenic Diabetes Insipidus
- Thyroid Dysfunction
- References
- Perrone and Chatterjee (2018) UpToDate, accessed 8/20/2018
- Micromedex, accessed 8/20/2018
- Mike Avila, MD (2018), email communication, received 8/15/2018