http://www.nimh.nih.gov/health/topics/obsessive-compulsive-disorder-ocd/index.shtml
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National Institute of Mental Health, National Institutes of Health
Obsessive-Compulsive Disorder (OCD) is a real illness. It can be treated with medicine and therapy. If you have OCD, you have repeated, upsetting thoughts. You do the same thing over and over again to make the thoughts go away. You feel like you cannot control these thoughts or actions.