LONG-TERM RISPERIDONE TREATMENT IN BIPOLAR DISORDER - 6-MONTH FOLLOW-UP

Antipsychotic agents, such as clozapine and risperidone, have been rep orted to be beneficial in the treatment of some bipolar patients. Many bipolar patients experience `breakthrough episodes' of mood disorder, with mania or depression recurring despite adequate ongoing levels of one or more mood-stabilizing medications. There are no controlled stu dies of breakthrough episodes, and there is little open experience to guide clinicians in pharmacotherapy of breakthrough episodes. This rep ort describes the outcome of adjunctive risperidone treatment in break through episodes of bipolar disorder. We assessed the outcome of openl y adding risperidone to the medication regimen of 12 outpatients with bipolar disorder, type I, who suffered breakthrough episodes despite a dequate maintenance medication (lithium, valproate, or carbamazepine, or a combination of these). Prospective ratings were made at each clin ical visit using the Clinical Global Impressions and Global Assessment of Functioning scales. Patients received risperidone for a mean of 6. 0 months (23.96 weeks, range 0.5-72 weeks) at a mean dose of 2.75 mg/d ay (range 1-4.5 mg/day). Four patients discontinued medication (two be cause of lack of efficacy at weeks 6 and 64, and two because of advers e events at weeks 0.5 and 23). Among the remaining eight patients, fou r experienced a 10-25 point improvement in Global Assessment of Functi oning scores and were rated much better on the Clinical Global Impress ion-Improvement scale. Although one patient suffered a major depressiv e recurrence (at week 22), no patient experienced worsening of mania. This small open series suggests a subgroup of bipolar patients with br eakthrough episodes may benefit from treatment with risperidone.