OBJECTIVE:

To evaluate the efficacy of lithium in the treatment of acute mania.

METHOD:

Systematic overview of the literature and meta-analysis of randomised controlled trials. Estimation of (i) the differences in the reduction in mania severity scores, and (ii) the ratio and difference in improvement response rates.

RESULTS:

A total of 658 patients from 12 trials were included. Treatment periods ranged from 3 to 4 weeks. The response rate ratio for lithium against placebo was 1.95 (95%CI 1.17-3.23). The mean number needed to treat was five (95%CI 3-20). Patients were twice as likely to obtain remission with lithium than with chlorpromazine (rate ratio = 1.96, 95%CI 1.02-3.77). The mean number needed to treat was four (95%CI 3-9). Neither carbamazepine nor valproate was more effective than lithium. The response rate ratios were 1.01 (95%CI 0.54-1.88) for lithium compared to carbamazepine and 1.22 (95%CI 0.91-1.64) for lithium against valproate. Haloperidol was no better than lithium on the basis of improvement based on assessment of global severity. The differences in effects between lithium and risperidone were -2.79 (95%CI -4.22 to -1.36) in favour of risperidone with respect to symptom severity improvement and -0.76 (95%CI -1.11 to -0.41) on the basis of reduction in global severity of disease. Symptom and global severity was as well controlled with lithium as with verapamil. Lithium caused more side-effects than placebo and verapamil, but no more than carbamazepine or valproate.

CONCLUSION:

The clinical trial evidence suggests that lithium should remain the first line treatment for acute mania.