Lithium Carbonate[Bipolar Disorder] Treatment of manic episodes of manic-depressive illness. Initiate treatment at 600-900 mg/day in 3 divided doses; increase to 1,200-1,800 mg/day in 3 divided doses to achieve serum lithium concentrations between 0.8 and 1.2 mmol/L. Adjust dose according to clinical response and trough serum level (12 h) after steady state is reached (4-5 days). After the acute manic episode subsides, adjust dose to maintain a level of 0.6-1.0 mmol/L. The average dosage range at this stage is usually 450-1,200 mg/day. If a satisfactory antimanic response is not obtained in 14 days, consider discontinuing lithium. Mild adverse effects can occur even if serum lithium levels are 1 mmol/L. Initial postabsorptive symptoms including g.i. discomfort, nausea, vertigo, muscle weakness, and a dazed feeling frequently disappear after stabilization of therapy. More common and persistent side effects: fine hand tremor, fatigue, thirst, polyuria. Mild to moderate toxic reactions occur at lithium levels of 1.5 to 2 mmol/L; moderate to severe reactions at levels 2 mmol/L. Progressive intoxication may be manifest3ed by confusion, increasing disorientation, muscle twitchings, hyper-reflexia, nystagmus, seizures, diarrhea, vomiting, and eventually coma and death. Maintain patients on lithium therapy under careful clinical and laboratory control throughout treatment. Means of obtaining accurate determination of serum lithium concentrations should be available, since frequent serum determinations are required especially during the initial period of treatment. Lithium toxicity is closely related to serum lithium concentrations and during treatment they should usually not exceed 1.5 mmol/L, if serious adverse reactions and lithium intoxication are to be avoided.
