Matching the bipolar patient and the mood stabilizer.

Bipolar disorder poses many treatment challenges, including "matching" a particular patient with the optimal treatment regimen. Although there are a number of extant guidelines to assist the clinician in selecting treatment, these recommendations are largely based on general variables and fail to take into account the subtleties and complications that confront a clinician in practice. An analysis of predictors of medication response in bipolar disorder provides a basis for matching patients with optimal medication regimens. Response to treatment may depend on the polarity of an episode or on clinical features such as mixed or psychotic symptomatology and rate of cycling. Comorbid psychiatric disorders such as substance abuse, anxiety disorders, or attention-deficit/hyperactivity disorder should also be considered in designing a treatment regimen. Similarly, medical conditions, especially metabolic abnormalities or kidney insufficiency, must be taken into account. Selection of medication may also involve an analysis of demographic factors, including family and personal history of response to a particular agent. When selecting the most appropriate mood stabilizer for a patient--particularly when polypharmacy is required--the clinician should keep potential side effects and drug interactions in mind. Randomized, controlled studies in bipolar populations are needed to further characterize optimal matching of patient and medication.