We discussed a case about an elderly woman with hx of T2DM, hypothyroidism, and bipolar disorder (in remission on Lithium), who presented with chronic progressive encephalopathy, polydipsia, polyuria, ataxia, tremors / myoclonic jerks, and AKI. She was found to have Lithium toxicity.

Lithium

• Lithium is almost entirely excreted by the kidneys, so even minor declines in function can trigger toxicity

Manifestations / Complications

• GI: nausea, vomiting, diarrhea
• Neuro (acute): encephalopathy, agitation, ataxia, neuromuscular excitability (tremors, myoclonic jerks), seizures, non-convulsive status epilepticus
• Neuro (chronic): Syndrome of Irreversible Lithium Effectuated Neurotoxicity (SILENT), which is persistent encephalopathy despite normalized Lithium levels
• Renal: Nephrogenic diabetes insipidus

Labs

• Check Lithium levels frequently because it may NOT have peaked yet!

Treatment

• Stop Lithium
• Monitor ABCs
• IVFs
• GI decontamination (activated charcoal is NOT effective for Lithium toxicity)
• Dialysis

Poison Control’s Number: 800-411-8080