Which medication is considered a mood stabilizer for the treatment of Bipolar Disorder?

Lithium is considered a primary mood stabilizer for the treatment of Bipolar Disorder. It is effective in both the acute management of manic episodes and in the long-term maintenance treatment to prevent recurrences of manic and depressive episodes. The mechanism of action of lithium involves the modulation of neurotransmitter release and the stabilization of mood, making it particularly suitable for patients with bipolar disorder who experience significant mood fluctuations.

The other medications listed, such as sertraline, fluoxetine, and citalopram, are selective serotonin reuptake inhibitors (SSRIs) primarily used to treat depression and anxiety disorders. While they may be beneficial for depressive episodes in bipolar disorder, they are not classified as mood stabilizers and can potentially trigger manic episodes if not used carefully in this population. Therefore, lithium stands out as the correct choice for its established role in managing the overall mood spectrum in patients with bipolar disorder.