Adjunctive escitalopram in Bipolar Depression: efficacy and safety

Introduction Despite the substantial burden associated with bipolar depression, options for treatment are limited and management of the depressive phase represents a major clinical challenge in the treatment of bipolar disorder. Antidepressants (ADs) are commonly prescribed in bipolar depression: it has been reported that ADs are the first-choice agent twice as often as mood stabilizers. However, data regarding their use are scarce and insufficient to guide treatment decisions in clinical practice. Method The primary objective of our study was to provide preliminary data on efficacy and safety of escitalopram as adjunctive treatment in bipolar depression. Secondary objectives were to evaluate pharmacokinetic interactions between escitalopram and drugs used for the treatment of bipolar mood disorders and to assess any possible influence of patient’s genotype on drug kinetics, efficacy and tolerability. The study was conducted at the Department of Psychiatry of the University of Pisa. Eligible patients were enrolled in a one-year open trial of escitalopram as adjunctive therapy to their concomitant treatment with mood stabilizers. Efficacy and tolerability of treatment were evaluated using evaluation scales repeated during the planned follow-up visits at 2nd, 4th, 8th and 16 th week and at the end of follow up period (1 year after enrollment). Blood levels of mood stabilizers and escitalopram were collected during first visit and repeated during follow up visits. Results Ten patients completed the 16 week trial, the lenght of antidepressant therapy recommended to avoid recurrences after a depressive episode. In those patients, the overall mean scores on HAM-D decreased from 15.7 (SD=5.8) at baseline to 8.2 (SD= 6.3) (Wilcoxon Signed Rank Test, z=- 2.193; P= 0.028); the CGI-S score decreased from 3.4 (SD=0.84) to 2.5 (SD=1.0) (z=-1.558; P=0.119). Mean HAM-D scores and mean CGI-S scores improved from baseline at all assessments in all patients. During the one-year follow-up period the most frequently observed side effects were dry mouth, nausea, sweating, increased body weight and somnolence. All patients had plasma concentrations of escitalopram which were within the therapeutic range described in the technical note of the drug. Conclusions In line with previous studies which have shown that selective serotonin re-uptake inhibitors may be an option in bipolar depression, our pilot study suggests that adjunctive escitalopram might be an useful and safe strategy in bipolar depression.