Study to evaluate the safety and efficacy of an FDA (Food and Drug Administration) approved medication in the treatment of a form of depression in epilepsy known as interictal dysphoric disorder with or without postictal depressive symptoms.

The study drug was approved by the FDA for the treatment of epileptic seizures and has also been found to be effective in the treatment of depressive episodes in subjects with manic-depressive illness but who do not suffer from epilepsy. Subjects are being asked to participate in this study to test the safety and efficacy of this study medication in subjects with epilepsy who also have a form of depression called interictal dysphoric disorder. The study will last for 7 months and will require seven visits.

You may be eligible if you:

• Must be 18 years of age or older
• Must have a history of epilepsy and have been diagnosed with interictal dysphoric disorder
• Must have a score of 20 or higher on the Cornell Dysthmia Scale which will be administered
• Cannot currently be taking lamotrigine or have taken an antidepressant or an antipsychotic drug in the past six months

This is a partial list of eligibility requirements.