A 10 year study found that "40 to 60 percent of patients with obsessive-compulsive disorder do not respond to adequate treatment trials with SSRIs, and agents that alter serotonin receptors and other neurotransmitter systems, such as dopamine and norepinephrine, as well as second-messenger systems may play a role in the treatment of obsessive-compulsive disorder."
Treatment for OCD often involves a combination of medications and psychotherapy. Scientists continue to explore which meds help the most, while cognitive behavioral therapy also continues to show promise.
Source: Psychiatric Services -- Abstracts: Kaplan and Hollander 54 (8): 1111
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