A Trial of Intranasal Ketamine for the Treatment of Obsessive-Compulsive Disorder

This study is being done to learn whether administration of intranasal (inhaled through the nose) ketamine reduces symptoms of obsessive-compulsive disorder (OCD). Ketamine has been approved by the U.S. Food and Drug Administration (FDA) as an anesthetic agent (a medicine to reduce pain during surgery and other procedures) but ketamine has not been approved by the FDA as a treatment for OCD. The investigators believe that ketamine may be effective in reducing symptoms of OCD due to its ability to decrease the activity of a specific brain chemical called glutamate. Previous studies have shown that people with OCD can have abnormal levels of glutamate in their brains. This is the first time that intranasal ketamine is being studied in people with OCD. However, studies have been done in the past using intravenous (IV; through a needle into a vein in your arm) ketamine in people with OCD, and intranasal ketamine has been studied in people with other psychiatric conditions. This research study will compare ketamine to placebo. The placebo looks exactly like ketamine, but contains no ketamine. At some time during the study, the investigators will give you ketamine. At another time, the investigators will give you placebo. Placebos are used in research studies to see if the results are due to the study drug or due to other reasons.