Table 2.

Symptoms and signs of lithium intoxication^a and situations associated with an increased risk of intoxication

Symptoms and signs	Risk situations
Mild intoxication:  Cognitive impairment, lethargia, tremor dysartria, nausea Moderate intoxication:  Disorientation, impaired gait, twitching of muscles, vomiting Severe intoxication:  Delirium, convulsions, ataxia, renal impairment	Lithium overdose Increased loss of water and/or salt (e.g. gastrointestinal infection, increased sweating) Decreased intake of water and/or salt (e.g. various disease states) Impaired renal elimination of lithium (renal disease, old age) Major surgery Concurrent treatment with thiazide diuretics and/or nonsteroidal antiinflammatory drugs

^aMay begin to appear with serum lithium levels above 1.2 mEq/L. However, intoxication is not incompatible with lower levels of serum–lithium since lithium is eliminated at a lower rate from the CNS than from the serum.