Back to table of contents Previous article Next article PerspectivesFull AccessThe International Society for Bipolar Disorders (ISBD) Task Force Report on Antidepressant Use in Bipolar DisordersIsabella Pacchiarotti, M.D., Ph.D., David J. Bond, M.D., Ph.D., Ross J. Baldessarini, M.D., Willem A. Nolen, M.D., Ph.D., Heinz Grunze, M.D., Rasmus W. Licht, M.D., Ph.D., Robert M. Post, M.D., Michael Berk, M.D., Ph.D., Guy M. Goodwin, F.Med.Sci., Gary S. Sachs, M.D., Leonardo Tondo, M.D., Robert L. Findling, M.D., Eric A. Youngstrom, Psy.D., Ph.D., Mauricio Tohen, M.D., Dr.P.H., Juan Undurraga, M.D., Ana González-Pinto, M.D., Ph.D., Joseph F. Goldberg, M.D., Ayşegül Yildiz, M.D., Lori L. Altshuler, M.D., Joseph R. Calabrese, M.D., Philip B. Mitchell, M.B.B.S., M.D., Michael E. Thase, M.D., Athanasios Koukopoulos, M.D., Francesc Colom, Psy.D., Ph.D., Mark A. Frye, M.D., Gin S. Malhi, M.D., Konstantinos N. Fountoulakis, M.D., Ph.D., Gustavo Vázquez, M.D., Ph.D., Roy H. Perlis, M.D., Terence A. Ketter, M.D., Frederick Cassidy, M.D., Hagop Akiskal, M.D., Jean-Michel Azorin, M.D., Marc Valentí, M.D., Ph.D., Diego Hidalgo Mazzei, M.D., Beny Lafer, M.D., Tadafumi Kato, M.D., Ph.D., Lorenzo Mazzarini, M.D., Anabel Martínez-Aran, Psy.D., Ph.D., Gordon Parker, M.D., Ph.D., Daniel Souery, M.D., Ph.D., Ayşegül Özerdem, M.D., Ph.D., Susan L. McElroy, M.D., Paolo Girardi, M.D., Michael Bauer, M.D., Ph.D., Lakshmi N. Yatham, M.D., Carlos A. Zarate, M.D., Andrew A. Nierenberg, M.D., Boris Birmaher, M.D., Shigenobu Kanba, M.D., Ph.D., Rif S. El-Mallakh, M.D., Alessandro Serretti, M.D., Ph.D., Zoltan Rihmer, M.D., Ph.D., Allan H. Young, M.D., Ph.D., Georgios D. Kotzalidis, M.D., Glenda M. MacQueen, M.D., Ph.D.N., Charles L. Bowden, M.D., S. Nassir Ghaemi, M.D., M.P.H., Carlos Lopez-Jaramillo, M.D., Ph.D., Janusz Rybakowski, M.D., Ph.D., Kyooseob Ha, M.D., Giulio Perugi, M.D., Siegfried Kasper, M.D., Jay D. Amsterdam, M.D., Robert M. Hirschfeld, M.D., Flávio Kapczinski, M.D., Ph.D., and Eduard Vieta, M.D., Ph.D.Isabella PacchiarottiSearch for more papers by this author, M.D., Ph.D., David J. BondSearch for more papers by this author, M.D., Ph.D., Ross J. BaldessariniSearch for more papers by this author, M.D., Willem A. NolenSearch for more papers by this author, M.D., Ph.D., Heinz GrunzeSearch for more papers by this author, M.D., Rasmus W. LichtSearch for more papers by this author, M.D., Ph.D., Robert M. PostSearch for more papers by this author, M.D., Michael BerkSearch for more papers by this author, M.D., Ph.D., Guy M. GoodwinSearch for more papers by this author, F.Med.Sci., Gary S. SachsSearch for more papers by this author, M.D., Leonardo TondoSearch for more papers by this author, M.D., Robert L. FindlingSearch for more papers by this author, M.D., Eric A. YoungstromSearch for more papers by this author, Psy.D., Ph.D., Mauricio TohenSearch for more papers by this author, M.D., Dr.P.H., Juan UndurragaSearch for more papers by this author, M.D., Ana González-PintoSearch for more papers by this author, M.D., Ph.D., Joseph F. GoldbergSearch for more papers by this author, M.D., Ayşegül YildizSearch for more papers by this author, M.D., Lori L. AltshulerSearch for more papers by this author, M.D., Joseph R. CalabreseSearch for more papers by this author, M.D., Philip B. MitchellSearch for more papers by this author, M.B.B.S., M.D., Michael E. ThaseSearch for more papers by this author, M.D., Athanasios KoukopoulosSearch for more papers by this author, M.D., Francesc ColomSearch for more papers by this author, Psy.D., Ph.D., Mark A. FryeSearch for more papers by this author, M.D., Gin S. MalhiSearch for more papers by this author, M.D., Konstantinos N. FountoulakisSearch for more papers by this author, M.D., Ph.D., Gustavo VázquezSearch for more papers by this author, M.D., Ph.D., Roy H. PerlisSearch for more papers by this author, M.D., Terence A. KetterSearch for more papers by this author, M.D., Frederick CassidySearch for more papers by this author, M.D., Hagop AkiskalSearch for more papers by this author, M.D., Jean-Michel AzorinSearch for more papers by this author, M.D., Marc ValentíSearch for more papers by this author, M.D., Ph.D., Diego Hidalgo MazzeiSearch for more papers by this author, M.D., Beny LaferSearch for more papers by this author, M.D., Tadafumi KatoSearch for more papers by this author, M.D., Ph.D., Lorenzo MazzariniSearch for more papers by this author, M.D., Anabel Martínez-AranSearch for more papers by this author, Psy.D., Ph.D., Gordon ParkerSearch for more papers by this author, M.D., Ph.D., Daniel SouerySearch for more papers by this author, M.D., Ph.D., Ayşegül ÖzerdemSearch for more papers by this author, M.D., Ph.D., Susan L. McElroySearch for more papers by this author, M.D., Paolo GirardiSearch for more papers by this author, M.D., Michael BauerSearch for more papers by this author, M.D., Ph.D., Lakshmi N. YathamSearch for more papers by this author, M.D., Carlos A. ZarateSearch for more papers by this author, M.D., Andrew A. NierenbergSearch for more papers by this author, M.D., Boris BirmaherSearch for more papers by this author, M.D., Shigenobu KanbaSearch for more papers by this author, M.D., Ph.D., Rif S. El-MallakhSearch for more papers by this author, M.D., Alessandro SerrettiSearch for more papers by this author, M.D., Ph.D., Zoltan RihmerSearch for more papers by this author, M.D., Ph.D., Allan H. YoungSearch for more papers by this author, M.D., Ph.D., Georgios D. KotzalidisSearch for more papers by this author, M.D., Glenda M. MacQueenSearch for more papers by this author, M.D., Ph.D.N., Charles L. BowdenSearch for more papers by this author, M.D., S. Nassir GhaemiSearch for more papers by this author, M.D., M.P.H., Carlos Lopez-JaramilloSearch for more papers by this author, M.D., Ph.D., Janusz RybakowskiSearch for more papers by this author, M.D., Ph.D., Kyooseob HaSearch for more papers by this author, M.D., Giulio PerugiSearch for more papers by this author, M.D., Siegfried KasperSearch for more papers by this author, M.D., Jay D. AmsterdamSearch for more papers by this author, M.D., Robert M. HirschfeldSearch for more papers by this author, M.D., Flávio KapczinskiSearch for more papers by this author, M.D., Ph.D., and Eduard VietaSearch for more papers by this author, M.D., Ph.D.Published Online:1 Nov 2013https://doi.org/10.1176/appi.ajp.2013.13020185AboutSectionsView articleAbstractSupplemental MaterialPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail View articleAbstractObjectiveThe risk-benefit profile of antidepressant medications in bipolar disorder is controversial. When conclusive evidence is lacking, expert consensus can guide treatment decisions. The International Society for Bipolar Disorders (ISBD) convened a task force to seek consensus recommendations on the use of antidepressants in bipolar disorders.MethodAn expert task force iteratively developed consensus through serial consensus-based revisions using the Delphi method. Initial survey items were based on systematic review of the literature. Subsequent surveys included new or reworded items and items that needed to be rerated. This process resulted in the final ISBD Task Force clinical recommendations on antidepressant use in bipolar disorder.ResultsThere is striking incongruity between the wide use of and the weak evidence base for the efficacy and safety of antidepressant drugs in bipolar disorder. Few well-designed, long-term trials of prophylactic benefits have been conducted, and there is insufficient evidence for treatment benefits with antidepressants combined with mood stabilizers. A major concern is the risk for mood switch to hypomania, mania, and mixed states. Integrating the evidence and the experience of the task force members, a consensus was reached on 12 statements on the use of antidepressants in bipolar disorder.ConclusionsBecause of limited data, the task force could not make broad statements endorsing antidepressant use but acknowledged that individual bipolar patients may benefit from antidepressants. Regarding safety, serotonin reuptake inhibitors and bupropion may have lower rates of manic switch than tricyclic and tetracyclic antidepressants and norepinephrine-serotonin reuptake inhibitors. The frequency and severity of antidepressant-associated mood elevations appear to be greater in bipolar I than bipolar II disorder. Hence, in bipolar I patients antidepressants should be prescribed only as an adjunct to mood-stabilizing medications.The efficacy and safety of antidepressant drug treatment in bipolar disorder is the subject of long-standing debate based on a scientific literature that is limited and inconsistent (1–6). The sparseness of high-quality clinical research hampers the formulation of sound clinical recommendations on the use of antidepressants in the treatment of bipolar disorder (7–12). We propose that a consensus formed by the experience and judgment of clinical and academic bipolar disorder experts, guided by the available research findings, may help in developing at least tentative treatment recommendations as additional research is awaited. Accordingly, the International Society for Bipolar Disorders (ISBD) appointed Dr. Vieta to assemble a task force of international experts to review the evidence base for benefits and risks of antidepressant treatment in bipolar disorder and to formulate clinical recommendations based on the consensus development process. This report represents a consensus statement from this endeavor.MethodConsensus MethodsThe ISBD Task Force was made up of a panel of global experts on bipolar disorder, selected according to an objective procedure based on a Scopus search of citations on the specific topic of antidepressant use in bipolar disorder (number of citations per candidate during the past 3 years). The most cited authors (including several ISBD nonmembers) and some additional authors from key geographical areas were identified and invited by e-mail to participate; 76% agreed to participate. An introductory meeting was held at the ISBD biennial congress (Istanbul, March 2012), where task force procedures were reviewed and agreed upon. These procedures focused on the discussion and integration of findings from peer-reviewed published research findings on the topic, including reviews and meta-analyses, as well as clinical trial reports. An expert coauthor (I.P.) was appointed to develop a first draft of a systematic review, to be circulated after initial review by the senior author (E.V.). The aims of the task force were to conduct a thorough and balanced review of research findings and to integrate them into an expert consensus, based on clinical experience and judgment, as well as research evidence, and to provide a synthesis of current knowledge supporting clinical recommendations for this important and timely topic. The final section of this report, which summarizes consensus statements, was achieved through a face-to-face meeting, personal and group e-mail correspondence, and serial iterative revisions of the report, in order to provide a final guide on the use of antidepressants in bipolar disorder. Funding for this international project was provided solely by the Spanish government.Search StrategyWe performed an extensive literature search on PubMed, using the following search terms, limited to human studies: antidepressant* AND (mania[ti] OR manic[ti]); antidepressant* AND (bipolar[ti] AND depressi*[ti]); antidepressant* AND (mixed[ti] AND state*[ti]); antidepressant* AND bipolar disorder AND maintenance[ti]; antidepressant* AND bipolar disorder AND comorbid*[ti]; antidepressant* AND switch AND (manic OR mania OR hypomani*); antidepressant* AND (cycle acceleration OR phase shift OR cycle frequen*); and antidepressant* AND (suicid*[ti] OR self-kill*[ti] OR self-harm*[ti]).We considered first-generation norepinephrine-serotonin reuptake inhibitors (SNRIs), including tricyclic and tetracyclic antidepressants; monoamine oxidase (MAO) inhibitors; and the modern antidepressants, including the dopamine-norepinephrine reuptake inhibitor bupropion, serotonin reuptake inhibitors (SSRIs), modern SNRIs, the norepinephrine-serotonin autoreceptor-specific antagonists mianserin and mirtazapine; the atypical, mixed monoamine-transporter inhibitors trazodone and nefazodone; and the melatonin M1 and M2 receptor agonist and 5-HT2c receptor antagonist agomelatine.We address here only antidepressant medications, not the treatment of bipolar depression in general. Hence, we did not include alternative or experimental agents such as sulfoadenosine-l-methionine; Hypericum perforatum (St. John’s wort); various mood stabilizers and antipsychotics with some evidence of antidepressant efficacy (e.g., lithium, lamotrigine, quetiapine, olanzapine, lurasidone); glutamatergic modulators including glycine and its analogues; ketamine, memantine, and other N-methyl-d-aspartate (NMDA) inhibitors; azapirone anxiolytics (buspirone, gepirone); stimulants (e.g., amphetamines, methylphenidate); the antinarcolepsy agents modafinil and armodafinil; and direct dopamine receptor agonist antiparkinsonian agents such as pramipexole. We also did not include nonpharmacological treatments, such as ECT, transcranial magnetic stimulation, vagus nerve stimulation, deep brain stimulation, intense light therapy, or psychological interventions.Systematic Review MethodsEach report considered was rated for methodological quality according to the Jadad scale (13) as poor (scores of 0–2) or acceptable-good (scores of 3–5; see the data supplement that accompanies the online edition of this article). Each report was rated A, B, C, or D for overall quality, as recommended by the Australian National Health and Medical Research Council (14), save for the applicability criterion (see the data supplement and Table 1). Included references may contain additional reports for particular questions and statements. Meta-analyses and reviews were used as evidence to support information that could not be drawn from individual studies. Figure 1 outlines how reports were selected.TABLE 1. Summary of Average Quality and Evidence Level of Studies for Each Topic Addressed in a Review of Antidepressant Use in Bipolar DisordersaTopicJadad ScoreEvidence LevelAntidepressant monotherapy3DAdjunctive antidepressants: short-term efficacy in acute depression4BPredictors of initial response to adjunctive antidepressants3DAdjunctive antidepressants: maintenance studies3.5CPredictors of long-term responsiveness to adjunctive antidepressant treatment3DAntidepressant use in mania and mixed states3DAntidepressants and affective switch (mania, hypomania, or mixed)4CAre newly emerging or increasing irritability and agitation, subclinical mixed states during antidepressant treatment a form of mood switching?3.5DAntidepressants and cycle acceleration3.5DAntidepressants and suicidality3Da The Jadad score is an indicator of study methodological quality (ranging from 0 to 5, with higher scores indicating higher quality). The grades for evidence level, which also reflect study quality, run from A (excellent) to D (poor). See the online data supplement.TABLE 1. Summary of Average Quality and Evidence Level of Studies for Each Topic Addressed in a Review of Antidepressant Use in Bipolar DisordersaEnlarge tableFIGURE 1. Flow Diagram of Study Design and Results in a Review of Antidepressant Use in Bipolar Disordersa Criteria for clinical response or remission were based on international standards, typically involving a decrease of ≥50% from baseline to a final score on a standard symptom rating scale (response) and a final depression score ≤7 (typically using the 17-item Hamilton Depression Rating Scale).Delphi MethodTo add a table of recommendations at the end of the systematic review, we conducted a survey using the Delphi method (15–17). Statements on antidepressant use in bipolar disorder that could be useful to clinicians were derived from the content of the literature search and classified into six common domains: acute treatment; maintenance treatment; monotherapy; switch to mania, hypomania, or mixed states and rapid cycling; use in mixed states; and drug class. Three survey rounds were conducted to develop consensus. The first survey included open-ended questions at the end of each section inviting participants to add comments and suggestions by e-mail. Later rounds were conducted online using eSurveysPro.com. The survey was sent to task force members for anonymous responses. Panel members rated survey items ranging from “essential” to “should not be included.” We calculated proportions of respondents rating each item. Survey items were classified as endorsed, rerated, or rejected.Endorsed items.Items rated by at least 80% of ISBD experts as essential or important were included in the ISBD recommendations.Rerated items.Items rated as essential or important by 65%−79% of panel experts were included in the next survey for rerating after considering feedback from first-round results. Panel members could decide whether they wanted to maintain or change their previous rating on these relatively controversial items. Items were rerated only once; if they did not achieve the criterion for endorsement, they were rejected.Rejected items.Items that were not included by at least 65% of panelists on the first round were rejected and excluded.The initial survey included 25 items. The second survey included 23 items. The briefer third survey consisted of five items that needed rerating.Twelve of the initial 25 items were endorsed and formed the section of the ISBD clinical recommendations of antidepressant use in bipolar disorder (Table 2).TABLE 2. International Society for Bipolar Disorders Clinical (ISBD) Recommendations for Antidepressant Use in Bipolar DisordersaDomainRecommendationAcute treatment1. Adjunctive antidepressants may be used for an acute bipolar I or II depressive episode when there is a history of previous positive response to antidepressants.2. Adjunctive antidepressants should be avoided for an acute bipolar I or II depressive episode with two or more concomitant core manic symptoms in the presence of psychomotor agitation or rapid cycling.Maintenance treatment3. Maintenance treatment with adjunctive antidepressants may be considered if a patient relapses into a depressive episode after stopping antidepressant therapy.Monotherapy4. Antidepressant monotherapy should be avoided in bipolar I disorder.5. Antidepressant monotherapy should be avoided in bipolar I and II depression with two or more concomitant core manic symptoms.Switch to mania, hypomania, or mixed states and rapid cycling6. Bipolar patients starting antidepressants should be closely monitored for signs of hypomania or mania and increased psychomotor agitation, in which case antidepressants should be discontinued.7. The use of antidepressants should be discouraged if there is a history of past mania, hypomania, or mixed episodes emerging during antidepressant treatment.8. Antidepressant use should be avoided in bipolar patients with a high mood instability (i.e., a high number of episodes) or with a history of rapid cycling.Use in mixed states9. Antidepressants should be avoided during manic and depressive episodes with mixed features.10. Antidepressants should be avoided in bipolar patients with predominantly mixed states.11. Previously prescribed antidepressants should be discontinued in patients currently experiencing mixed states.Drug class12. Adjunctive treatment with norepinephrine-serotonin reuptake inhibitors or tri- and tetracyclics should be considered only after other antidepressants have been tried, and should be closely monitored because of an increased risk of mood switch or destabilization.a From an initial 25 items in six domains, the 12 presented here were rated by at least 80% of ISBD experts as essential or important and were included in the ISBD recommendations.TABLE 2. International Society for Bipolar Disorders Clinical (ISBD) Recommendations for Antidepressant Use in Bipolar DisordersaEnlarge tableResultsSearch ResultsA summary of our literature search and review is presented in Figure 1.EfficacyAntidepressant monotherapy.Antidepressant monotherapy is widely regarded as contraindicated for patients with bipolar disorder because of the weak evidence for efficacy and the potential risk for excessive mood elevation (switches). An elevated risk of mood switching was first observed in early trials that compared imipramine monotherapy, lithium monotherapy, lithium plus imipramine, and placebo (18, 19). Imipramine monotherapy was followed by more manic episodes than combination therapy with imipramine and lithium and was not superior to lithium in preventing depressive episodes.To date, the largest randomized placebo-controlled trial assessing antidepressant monotherapy in bipolar depression has been the EMBOLDEN II (Efficacy of Monotherapy Seroquel in Bipolar Depression) study (20), in which paroxetine was included as an active comparator to quetiapine and placebo in 740 acutely depressed patients with bipolar I or II disorder. Compared with placebo, paroxetine did not result in significant symptomatic improvement as rated on the Montgomery-Åsberg Depression Rating Scale (MADRS) in either bipolar type, whereas quetiapine (at 300 and 600 mg/day) separated from placebo without evidence of a dose effect. The study is limited by its use of a moderate, fixed dose of paroxetine (20 mg/day). A small randomized controlled trial of escitalopram monotherapy (21), an uncontrolled trial of fluoxetine (22), and a randomized controlled trial of fluoxetine or lithium monotherapy and placebo (23) found some support for the efficacy of these drugs in depressed bipolar II patients, with no evidence of mood switching.Conclusions.Overall, available clinical trials do not provide adequate support for the efficacy of antidepressant monotherapy in acute bipolar depression, but the evidence base is poor (D) and inconclusive (Table 1). Although the evidence might be rated C for depression in bipolar II patients, the studies focusing on such cases are marred by methodological shortcomings and possibly selective reporting.Adjunctive antidepressants: short-term efficacy in acute depression.Short-term trials of adjunctive antidepressant treatment have reported mixed results, perhaps best exemplified by the contrasting findings in the two largest placebo-controlled trials carried out to date. The first of these (24) compared the efficacy and safety of olanzapine monotherapy (5–20 mg/day, N=370) to placebo (N=377) in depressed bipolar I patients in an 8-week randomized double-blind trial with a small exploratory arm with several dosages of olanzapine-fluoxetine combinations. The olanzapine-fluoxetine combinations were more effective than olanzapine alone or placebo in improving MADRS depression scores at weeks 4–8. Limitations of the study included its lack of a fluoxetine monotherapy arm and a substantial dropout rate (38.5%).In the second trial (25), depressed bipolar I or II patients (N=366) receiving treatment with a mood stabilizer (lithium, valproate, carbamazepine, or other antimanic agents approved by the U.S. Food and Drug Administration, alone or in combination) were randomly assigned to receive adjunctive antidepressants (bupropion or paroxetine) or placebo for up to 26 weeks. Adjunctive antidepressants were no more effective than placebo at any time, and overall, 23.5% of patients given an antidepressant and 27.3% given placebo met criteria for enduring recovery. Limitations of the trial included its use of already well treated patients, its long duration, and the study requirement for sustained improvement.A smaller placebo-controlled study (26) also found no significant differences in efficacy among paroxetine, imipramine, or placebo as adjuncts to mood stabilizers. Conversely, a single-blind randomized trial (27) of short duration and lacking a control found significant improvement after 6 weeks in depressed bipolar I and II patients treated with mood stabilizers plus paroxetine or venlafaxine (28).Several meta-analyses have statistically combined data from some or all of these antidepressant studies. One such study (29) found higher response rates with an antidepressant compared with placebo and no increase in risk of manic switch (29), but it suffered from being heavily weighted by one large olanzapine-fluoxetine study (24). A later meta-analytic review (30) found nonsignificant differences between antidepressants and placebo in response and remission rates (p=0.06), which would have been even less favorable if the analysis had used a random-effects rather than a fixed-effects model (31). Another recent random-effects meta-analysis (32) found superiority of antidepressants over placebo (relative risk=1.43, 95% CI=1.11–1.84; z=2.76, p=0.006).Finally, a large naturalistic study (33) found short-term antidepressant treatment (with or without mood stabilizers) in acute major depressive episodes to be similarly effective in a total of 1,036 patients with bipolar I disorder, bipolar II disorder, and unipolar depression.Regarding possible predictors of short-term response to antidepressants in depressed bipolar patients, two naturalistic trials in acutely depressed bipolar I and II patients (34, 35) found that the most significant predictors of beneficial responses were previous response to antidepressants and a less severe illness course. In a naturalistic follow-up study (36), short-term recovery from depression in bipolar I or II disorder was neither hastened nor prolonged when antidepressants were added to a mood stabilizer in the presence of syndromal or subsyndromal hypomanic symptoms.Conclusions.Overall, the available evidence (category B) supports the efficacy of the olanzapine-fluoxetine combination in bipolar depression, indicates a lack of positive effects of paroxetine or bupropion added to mood stabilizers, and is otherwise inconsistent. The overall evidence quality of predictors of response to antidepressants is rated D, because of inconclusiveness and possible bias of findings (Table 1).Adjunctive antidepressants: long-term maintenance studies.For modern antidepressants, only two randomized controlled trials lacking placebo controls have examined the effects of continuing antidepressant treatment after favorable short-term responses in bipolar I depression (37, 38); notably, both trials involved patients who showed favorable short-term responses to antidepressant treatment. In one trial, depressed bipolar I or II patients who responded to initial treatment with venlafaxine, bupropion, or sertraline added to standard mood stabilizers after 2 months (50%−60% of each group) continued these treatments for up to 1 year, and only 15%−25% had no further episodes (37, 39). In the second trial (38), among 70 depressive bipolar I or II patients who had remitted for ≥8 weeks during treatment with a standard mood stabilizer plus an antidepressant (usually an SSRI, venlafaxine, or bupropion), antidepressant continuation showed nonsignificantly less severe depressive symptoms but a significant delay in recurrence of new depressive episodes, except that rapid-cycling patients experienced more depressive recurrences with an antidepressant.A nonrandomized uncontrolled trial (40), again involving patients showing favorable short-term responses, examined the effect of continuing or discontinuing antidepressant treatment for bipolar I and II patients who had remitted from a depressive episode for ≥6 weeks after addition of an antidepressant to a mood stabilizer. Over 1 year of follow-up, patients who discontinued antidepressant treatment experienced a shorter latency to depressive relapse (χ2=9.63, p=0.002) and were more likely to relapse (70% compared with 36%).In contrast to these findings, a meta-analysis of long-term antidepressant efficacy in bipolar depression (41) found that compared with mood stabilizer treatment alone, adjunctive antidepressants provided little protection from depression and tended to increased mania-hypomania, resulting in an unfavorable risk-benefit ratio for long-term antidepressant use in bipolar I disorder.Examining possible predictors of long-term responsiveness to adjunctive antidepressants in the Stanley Foundation Bipolar Network study (42), the research team found that depressed bipolar patients who achieved an initial response during 10 weeks of adjunctive antidepressant treatment (bupropion, sertraline, or venlafaxine) were more likely to maintain response with the same continuation regimen. Similarly, in a randomized double-blind placebo-substitution study with fluoxetine monotherapy in bipolar II depression (23), initial response to antidepressant treatment was associated with fewer relapses if antidepressant treatment was continued for up to 50 weeks.Conclusions.Long-term trials involving addition of antidepressants to ongoing mood-stabilizing treatments are scant and have yielded ambiguous, inconclusive findings, despite a moderately favorable quality score (C) for the evidence and despite reliance on samples enriched for probable short-term antidepressant response. For predictors of response, the lack of adequate controls and reliance on enriched patient samples led to a D rating of available evidence (Table 1).Antidepressant use in mania and mixed states.Despite a lack of controlled trials of adjunctive antidepressants during manic, hypomanic, or mixed episodes, most clinicians avoid their use during mixed episodes for fear of worsening mania, and without improving mixed-state depressive symptoms (36, 43–46). Indeed, no evidence of efficacy is available for antidepressants in mania or mixed states.Nevertheless, in an observational study, 21.9% of 2,416 manic patients were taking antidepre