Mixed states in bipolar disorder have long been recognized. Over a century ago, it was argued that mixed states were the most common episodes in manic-depressive illness. A mixed state is defined as a person who is experiencing symptoms of both depression and mania.

Currently, a person must have depression plus 3 or more manic symptoms for the episode to be diagnosed mixed. Using this narrow view, less than 10% of episodes in patients with bipolar disorder would meet criteria for a mixed episode. A broader view requires that the person have at least 2 manic symptoms. Using this broader view, data suggest that about 50% of episodes in bipolar disorder would be diagnosable as mixed states.

Studies suggest that the majority of persons with a depressive mixed state have bipolar disorder type II. Many people who have a mixed state will also have major depression. Even with such high potential rates of mixed episodes in both bipolar disorder and major depression, there have been few studies addressing the issue.

The purpose of this study is to look at how effective Geodon is in treating the depressive mixed state in people with bipolar or major depression. This will be the first clinical trial that is both double-blind and randomized.

We plan on enrolling 25 subjects from each of the four sites. After signing a consent form, subjects will be screened and asked to have a physical and specific safety labs done to make sure they can safely participate in the study. After the screening visit, subjects will be randomly, like a flip of a coin, placed into one of two groups. One group will get the study drug, Geodon. The other group will get placebo, a sugar pill. Neither the doctor nor subject will know in which group the subject has been placed.

Subjects will see the doctor once a week for 6 weeks. During each visit, we will check and treat any side effects. We will ask questions about mood and go through a number of rating scales and assessments that will look at mood and symptoms. Subjects will also fill out questionnaires at each visit to assess their moods and see how the study is going. At the final visit, subjects will have the same physical exam and lab tests done as in the initial visit.

Inclusion Criteria:

• Diagnosis of bipolar disorder type II, or unipolar major depressive disorder
• If female, non-pregnant/non-lactating
• If a sexually active female of reproductive potential, must be using adequate contraception (i.e., oral contraceptives, barrier protection, or prior tubal ligation)
• Currently meets Diagnostic and Statistical Manual, 4th edition (DSM-IV) criteria for a major depressive episode, and presence of 2 or 3 DSM-IV manic criteria, present for the majority of the time during the past week.
• All other baseline psychotropic drugs will be allowed to be continued unchanged. However, if antidepressant use has been initiated in the previous 2 months, or was thought to be contributing to the depressive mixed state, then antidepressant medications would be discontinued 4 weeks before starting the study.

One potential limitation in relation to secondary analyses would be sample size. The randomized study design should account for most potential confounding effects, but residual confounding cannot be completely eliminated without larger studies.