Six trials were considered in the review (n=1,561, range 60 to 463).
The reviewers reported that one study indicated lithium was superior to placebo in preventing mania and hypomania in recently manic or hypomanic patients. Another study indicated lithium was superior to placebo in preventing mania and hypomania in depressed bipolar I patients. One study indicated that lithium was not statistically different to divalproex in terms of mood disorder symptoms. Two studies were interpreted as not demonstrating that divalproex was superior to lithium. One study indicated that lithium and LMT did not differ in efficacy in preventing mood episodes and that olanzapine was superior to lithium in preventing recurrence of manic and mixed episodes. Summaries of individual studies were reported.
The authors stated that lithium was associated with higher rates of nausea, diarrhoea, tremor and somnolence than placebo. Other comparisons were reported.