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Obsessive-Compulsive Disorder (OCD)


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Last full review/revision Jun 2020| Content last modified Jun 2020
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What is obsessive-compulsive disorder (OCD)?

Obsessions are things you just can't stop thinking about, even if you want to. They could be worries, ideas, images, or urges to do something. Having an obsession usually makes you anxious and uncomfortable.

A compulsion is a strong urge to do something over and over even though you don't want to or don't think you should. A compulsion often involves doing something to relieve the anxiety of an obsession. For example, if you're obsessed with germs you may have a compulsion to wash your hands many times a day even though your hands aren't dirty.

Obsessive-compulsive disorder (OCD) is a mental disorder that includes obsessions, compulsions, or both.

What are the symptoms of OCD?

Common obsessions include:

  • Worry about catching germs, such as from touching doorknobs

  • Worry about some important safety action, such as locking the front door or turning off the stove

  • Concern that your possessions aren't in order, for example, items aren’t lined up evenly on your table or in your closet

People may try to ignore or control their obsessions. But if they can't, they may get more anxious.

Common compulsions include:

  • Washing or cleaning

  • Checking on things, such as checking over and over to make sure a door is locked

  • Counting

  • Putting things in a certain order or pattern

Usually, the compulsion has to be done exactly the same way each time and sometimes repeated a specific number of times.

Some compulsions can be noticed by others (such as repeatedly locking and unlocking a door). Other compulsions are more private (such as counting to oneself).

How can doctors tell if I have OCD?

Most people worry about things. And lots of people are very clean and orderly and have particular ways they like to do things. Doctors think having obsessions or compulsions is a disorder only if they:

  • Make you very upset

  • Take up a lot of time (at least an hour a day)

  • Cause problems in your daily life

For example, many people once in a while leave their house and then go back to check that the stove is off. But you have OCD if you keep going back to the house over and over to check that you turned off the stove. Having OCD can lead to problems in your life, for example, always being late for work because of the constant checking.

How do doctors treat OCD?

Doctors treat OCD using one or both of the following:

  • Having a therapist slowly expose you to the things that cause your obsessions, but not letting you perform the compulsions

  • Antidepressant medicines

For example, if you're obsessed about germs and have a compulsion to wash your hands, the therapist may ask you to touch a clean toilet seat and then not wash your hands.

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