Table II.

 Clinical Manifestations of Lithium Toxicity

Mild toxicity (serum lithium concentration=1.5–2.0 mmol/L

Lethargy

Drowsiness

Coarse hand tremor

Muscular weakness

Nausea/vomiting

Diarrhea

Moderate toxicity (serum lithium concentration=2.0–2.5 mmol/L)

Confusion

Dysarthria

Nystagmus

Ataxia

Myoclonic twitches

Electrocardiographic changes (flat or inverted T waves)

Severe toxicity (serum lithium concentration >2.5 mmol/L)

Grossly impaired consciousness

Increased deep tendon reflexes

Seizures

Syncope

Renal insufficiency

Coma

Death

Reprinted with permission from Finley et al. ¹⁰