Prophylactic efficacy of carbamazepine in manic-depressive illness.

Seven patients with rapidly cycling, lithium-resistant affective illness were followed for an average of 1.7 years during prophylactic treatment with carbamazepine administered on either a blind or an open basis. The number of manic and depressive episodes per year decreased significantly--from 16.4 before treatment to 5.6 during carbamazepine treatment; severity and duration of episodes were also reduced. Six of seven patients relapsed after carbamazepine dose reduction or discontinuation. These preliminary data add further support to the growing evidence that carbamazepine may be useful in the acute and prophylactic treatment of some lithium-resistant patients.