Treatment options for acute depression in bipolar disorder

Objective: The burden of depression represents the most debilitating dimension for the majority of patients with bipolar disorder and dominates the long-term course of the illness. The purpose of this manuscript is to review the evidence base of the available treatment options for bipolar depression within two frequent clinical scenarios.

Methods: The evidence is largely based on a systematic literature search and appraisal that was part of the development of the German Guideline for Bipolar Disorders. All relevant randomized controlled trials were critically evaluated.

Results: Overall, the number of suitably controlled studies for the treatment of bipolar depression is relatively low. There are two common scenarios. Scenario A, if a patient with bipolar depression is currently not being treated with a mood-stabilizing agent (de novo depression, first or subsequent episode), then quetiapine or olanzapine are options, or alternatively, carbamazepine and lamotrigine can be considered. Antidepressants are an option for short-term use, but whether they are best administered as monotherapy or in combination with mood-stabilizing agents is still controversial. In practice, most clinicians use antidepressants in combination with an antimanic agent. Scenario B, if a patient is already being treated optimally with a mood-stabilizing agent (good adherence and appropriate dose) such as lithium, lamotrigine is an option. There is no evidence for additional benefit from antidepressants where a patient is already being treated with a mood stabilizer; however, in practice an antidepressant is often trialled. Efficient psychotherapy is an important part of the treatment regimen and should span all phases of the illness.

Conclusions: Treatment decisions in bipolar depression involve a range of different pharmacological and non-pharmacological options. Monitoring potential unwanted effects and the appropriateness of treatment can help to effectively balance benefits and risks in individual situations. However, the quality of the assessment and reporting of risks in clinical trials need to be improved to better inform treatment decisions.