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• Obsessive-compulsive disorder
• Obsessive-compulsive personality disorder
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• Treatments for obsessive-compulsive illnesses

An obsession is a persistent (continuous) and recurring thought that a person is unable to control. A person suffering from obsessive thoughts often has symptoms of anxiety (uneasiness or dread) or emotional distress. To relieve this anxiety, a person may resort to compulsive behavior.

A compulsion is an irresistible impulse or desire to perform some act over and over. Examples of compulsive behavior are repetitive hand washing or turning a light on and off again and again to be certain it is on or off.

Although performing the specific act relieves the tension of the...