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Obsessive compulsive disorder (OCD)

Obsessive compulsive disorder (OCD) can affect you in different ways. It usually causes a particular pattern of thoughts and behaviours.

This pattern has 4 main steps:

  1. Obsession - an unwanted and distressing thought, image or urge repeatedly enters your mind.
  2. Anxiety - the obsession provokes a feeling of intense anxiety or distress.
  3. Compulsion - repetitive behaviours or mental acts that you feel driven to perform. These can be a response to the obsessive thought pattern.
  4. Temporary relief - the compulsive behaviour relieves the anxiety for a short while. But the obsession and anxiety soon return, causing the cycle to begin again.

It's possible to have obsessive thoughts, with or without the compulsion or urge to act. You may experience both.

Obsessive thoughts

Most of us, at some point, will have unpleasant or unwanted worrying thoughts or thoughts that make us anxious. This can be thinking you may have forgotten to lock the door of the house. You can even have sudden unwelcome violent or offensive mental images. Many of these thoughts go away as quickly as they appear.

You may have an obsession if you have a persistent, unpleasant thought that takes over your thinking. This thought may interrupt all your other thoughts. It can make it hard for you to focus on other daily activities.

Some common obsessions include:

  • fear of deliberately harming yourself or others
  • intense worry about catching a disease or infection
  • thinking about having to do things in a certain order or number of times to feel safe and reduce anxiety

You may have unwanted sexual thoughts or images which you fear you may act on. While these thoughts can cause extreme distress, it doesn't mean you will act on them.

Compulsive behaviour

Compulsions are things you do or ways you behave in response to the thoughts that make you anxious. The actions usually provide relief from the distress for a short while. 

For example, if you are afraid of catching germs, you may wash your hands over and over again. Washing your hands reduces the worry that you have germs on your hands. But as that thought comes back, the urge to wash your hands increases again.

People with OCD know that compulsive behaviour is irrational (does not make sense). But they do it because it reduces distress for a short while.

Common types of compulsive behaviour include:

  • excessive cleaning and hand washing
  • checking - such as checking doors are locked or that switches and appliance are off
  • counting and doing the same thing many times
  • ordering and arranging
  • hoarding
  • asking for reassurance
  • repeating words in their head
  • thinking 'neutralising' thoughts to counter the obsessive thoughts
  • avoiding places and situations that could trigger obsessive thoughts

Not all compulsive behaviours will be obvious to other people. When they are not obvious they are called "covert" behaviours. When they are obvious, they are called "overt" behaviours.

Getting help

Get help if you think you have OCD and it's having a negative impact on your life.

If you think a friend has OCD, find out if their thoughts or behaviours are causing problems for them. For example, in their daily routines and quality of life.

OCD is unlikely to get better on its own. Treatment and support can help you manage your symptoms.

To get help, talk to your GP. They can refer you to local psychological support services.

You may feel upset and hopeless when trying to manage your symptoms. If so, phone the Samaritans on 116123.

Some people with OCD may also develop other serious mental health problems, including:

People with OCD and severe depression may also have suicidal feelings.

Related topic

Clinical depression

Generalised anxiety disorder in adults

Content supplied by the NHS and adapted for Ireland by the HSE.

page last reviewed: 21/03/2019
next review due: 21/03/2022

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