Pre Test Infomation: Recommended specimen: just before the next dose is due at steady state.
Lithium is used to suppress the manic phase of manic-depressive psychosis. It is distributed throughout the total water spaces of the body and is excreted primarily by the kidney. Toxicity from lithium salts leads to ataxia, slurred speech and confusion. Since the concentration of lithium in the serum varies with the time after the dose, blood for lithium determination should be drawn at a standard time, preferably 8 to 12 hours after the last dose (trough values). This assay is useful for monitoring therapy of patients with bipolar disorders, including recurrent episodes of mania and depression and to evaluate lithium toxicity.