Bipolar disorder affects 2.4 million adults in the USA between the ages of 18-65 and has considerable economic impact on our society. Bipolar mania accounts for 1 in 7 psychiatric emergencies and is associated with significant morbidity and mortality. The purpose of the study is to evaluate the safety and efficacy of open-label memantine in the acute management of adults with bipolar I disorder hospitalized for mania.

Inclusion Criteria:

• Patients must have a documented clinical diagnosis of bipolar I disorder and must be currently experiencing a manic or mixed episode.
• Patients must be voluntarily hospitalized with a primary diagnosis of mania.

Exclusion Criteria:

• Rapid cycling bipolar disorder.
• Suicidal risk.
• First manic episode.
• ECT, clozapine or a depot neuroleptic in the past 3 months.
• Substance dependence.
• Known HIV infection.
• Co-morbid serious, uncontrolled systemic illness.