Pharmacotherapy of bipolar disorder is a complex and rapidly evolving field. The development of new treatments has helped to refine concepts of illness subtypes and generated important new management options. Although the mood stabilizers—the first-line agents lithium, valproate, and lamotrigine and the alternative agents carbamazepine (CBZ) and oxcarbazepine (OXC)—are considered the primary medications for bipolar disorder, antipsychotics, antidepressants, anxiolytics, and a new generation of anticonvulsants are commonly combined with mood stabilizers in clinical settings (American Psychiatric Association 2002; Ketter 2005; Suppes et al. 2005). These diverse medications have varying pharmacodynamics, pharmacokinetics, drug–drug interactions, and adverse effects, thus offering not only new therapeutic opportunities but also a variety of new potential pitfalls.