The most efficacious agents are likely those with bimodal stabilizing properties, such as lithium, carbamazepine, and quetiapine. In fact, on the strength of favorable efficacy data obtained in patients with major depressive symptoms accompanying bipolar disorder, quetiapine recently became the first agent to be indicated by the FDA for monotherapeutic use in the treatment of bipolar depression, including BPII depression. Aside from the aforementioned agents, lamotrigine also shows promise in the treatment of BPII.