Comparison of Standard and Low Serum Levels of Lithium for Maintenance Treatment of Bipolar Disorder

Abstract
In recent years, lower serum levels have been recommended for maintenance therapy with lithium. We studied 94 patients with bipolar disorder in a randomized, double-blind, prospective trial of two different doses of lithium for maintenance therapy: the "standard" dose, adjusted to achieve a serum lithium concentration of 0.8 to 1.0 mmol per liter, and a "low" dose, resulting in a serum concentration of 0.4 to 0.6 mmol per liter. The group medians of the patients' average serum lithium levels were 0.83 mmol per liter for the patients in the standard-range group and 0.54 mmol per liter for those in the low-range group.