Antidepressants were superior to placebo in reducing new depressive episodes in bipolar disorders without increasing risk of new manic/hypomanic episodes either used as monotherapy or in combination with MS .
Subgroup analyses revealed that greater benefit and lower risk may be achieved in BD II than in BD I. However , compared with MS monotherapy , AD monotherapy significantly increased the risk of affective switch with no improvement in prophylaxis of new depressive episodes .
CONCLUSIONS Reduced new depressive episodes may be achieved by long-term AD treatment with no significantly increased risk of new manic/hypomanic episodes in BD , particularly in BD II .
The elevated risk of affective switch  of AD monotherapy compared with MS monotherapy may be contributed to the protective effect of MS in diminishing manic/hypomanic episodes .
OBJECTIVE Efficacy and safety of long-term use of antidepressants ( AD ) in bipolar disorder ( BD ) patients remains highly controversial .
Here we performed a meta- analysis of r and omized controlled trials ( RCTs ) exploring the efficacy and safety of long-term AD use in BD patients .
Lithium carbonate and imipramine in prevention of affective episodes. A comparison in recurrent affective illness.
Patients with recurrent affective illness ( N-122 ) were r and omly assigned to lithium carbonate , imipramine , or placebo therapy for two years following discharge from hospitalization for acute depression . Patients were classified as bipolar or unipolar based on the presence or absence of a history of mania . With bipolar patients lithium carbonate was significantly more effective than imipramine or placebo in preventing affective episodes ( ie , manic or depressive attacks severe enough to require hospitalization or use of non study drugs ) . There was a relatively high incidence of manic episodes on imipramine . Unipolar patients responded equally well to lithium carbonate or imipramine . Both treatments were significantly more effective than placebo . The difference between treatments was due primarily to depressive episodes ; manic episodes occurred infrequently and were evenly distributed across treatment groups . There was no significant difference between  lithium carbonate and imipramine  among unipolar patients
Antidepressants were superior to placebo in reducing new depressive episodes in bipolar disorders without increasing risk of new manic/hypomanic episodes either used as monotherapy or in combination with MS .
Subgroup analyses revealed that greater benefit and lower risk may be achieved in BD II than in BD I. However , compared with MS monotherapy , AD monotherapy significantly increased the risk of affective switch with no improvement in prophylaxis of new depressive episodes .
CONCLUSIONS Reduced new depressive episodes may be achieved by long-term AD treatment with no significantly increased risk of new manic/hypomanic episodes in BD , particularly in BD II .
The elevated risk of affective switch  of AD monotherapy compared with MS monotherapy may be contributed to the protective effect of MS in diminishing manic/hypomanic episodes .
OBJECTIVE Efficacy and safety of long-term use of antidepressants ( AD ) in bipolar disorder ( BD ) patients remains highly controversial .
Here we performed a meta- analysis of r and omized controlled trials ( RCTs ) exploring the efficacy and safety of long-term AD use in BD patients .