Bipolar disorders are a class of Axis I mood disorders with severe physical, social, and psychological consequences to the patient, the patient's friends and family, and society as a whole. According to the Diagnostic and Statistical Manual of Mental Disorders, 4th ed., the lifetime prevalence for the three main types of bipolar disorders (bipolar type I, bipolar type II, and cyclothymic disorder) combined is approximately 1-2% percent, and unlike major depressive disorders, bipolar disorder is equally common among both men and women. The disorder appears to be mostly genetic, with a concordance rate of 40% among monozygotic twins and 15-20% among first degree relatives.
             As the name implies, patients who suffer from bipolar disorder constantly shift between the two poles of the affective spectrum, that is, from depression to mania (or hypomania). There is no specific pattern that allows clinicians to predict what affective state the patient will present next, nor when he or she will cycle into a manic or depressive state. The fact that many patients can often last in a state of affective normalcy for years and then suddenly lapse into depression or mania makes this disorder horrendously difficult for the patient, clinician, and anyone involved in the patient's life.
             The category of bipolar disorder is comprised of three distinct disorders, the first and most common of which is bipolar type I disorder. In this disorder, patients experience episodes of both depression and full-blown mania, normally in a somewhat slow cycle. The depressive episodes are similar to those found in major depression, and if left untreated will usually withdraw in 3 to 4 months. Manic episodes are much more difficult to predict, as they are particularly unique to each individual. Because mania is the defining feature of bipolar disorder (i.e. the differentiating criteria between bipolar and unipolar depression), some time should be spe...