Intravenous Ketamine in the Treatment of Obsessive-Compulsive Disorder

Inclusion Criteria: * Male or female patients, 21-65 years * Women of childbearing potential must agree to use a medically accepted means of contraception for the duration of the study * Primary diagnosis of Obsessive-Compulsive Disorder as assessed by the SCID-P, with symptoms for at least 1 year (Patients who meet criteria for OCD will be required to be medication free or have all psychotropics aside from SSRIs and as needed benzodiazepines tapered. Prior to study entry, proscribed psychotropics are tapered, and subjects must be on the same SSRI for at least 8 weeks with no change in dose for at least 4 weeks and throughout the study. However, subjects will be allowed to use benzodiazepines as needed throughout the study.) * History of a failure to respond to at least two (2) adequate pharmacotherapy trials and CBT for OCD * Subjects must have scored ≥ 21 on the Y-BOCS at Screening, and to not be in remission on Treatment Day #1, and Treatment Day #2 * Each subject must have a level of understanding sufficient to agree to all tests and examinations required by the protocol and must sign an informed consent document * Subjects must be able to identify a family member, physician, or friend who will participate in the Treatment Contract and serve as an emergency contact. Exclusion Criteria: * Women who plan to become pregnant within the next six months, are pregnant or are breast-feeding * Non-English speakers * Any unstable medical illness including hepatic, renal, gastroenterologic, respiratory, cardiovascular, endocrinologic, neurologic, immunologic, or hematologic disease * Clinically significant abnormal findings of laboratory parameters, physical examination, or ECG * Lifetime history of schizophrenia, schizoaffective disorder, bipolar disorder, mental retardation, or pervasive developmental disorders * Current evidence of psychotic or manic symptoms * Drug or alcohol abuse or dependence within the preceding 6 months * Lifetime abuse or dependence on ketamine or phencyclidine * Patients judged by study investigator to be at high risk for suicide * Current use of psychotropics other than SSRIs