Which treatment is classified as a mood stabilizer for bipolar disorder?

Lithium is classified as a mood stabilizer and is primarily used in the treatment of bipolar disorder. Its effectiveness in stabilizing mood and preventing both manic and depressive episodes makes it a cornerstone in the management of this condition. The exact mechanism of action of lithium is not fully understood, but it is believed to involve the modulation of neurotransmitter levels and neuroprotective effects, which contribute to mood stabilization.

Valproate is often considered an alternative mood stabilizer, especially for rapid cycling or mixed episodes, but it is not as quintessential to bipolar treatment as lithium is. Sertraline and fluoxetine are both selective serotonin reuptake inhibitors (SSRIs) and are primarily used as antidepressants. While they may be helpful in treating depressive episodes in bipolar disorder, they are not classified as mood stabilizers and carry a risk of inducing mania if not used in conjunction with a mood stabilizer. Thus, lithium remains the definitive choice for reliable mood stabilization in bipolar disorder.