Obsessive compulsive disorder (OCD)

Also known as OCD

Key points about obsessive compulsive disorder

  • OCD is diagnosed when you have regular and ongoing thoughts and urges that are unwanted and cause you distress.
  • These are referred to as obsessions and can include themes of disaster, health and hygiene, dirt, sex, violence, religious and other taboos and self-worth.
  • To try and feel better, you engage in repetitive behaviours (compulsion) eg, cleaning, checking, counting or repeating words or phrases.
  • This may help for a short time, but over time the compulsion has less effect on your anxiety. 
  • Seek help if you are worried about yourself or someone you care for.
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OCD is not just about being careful, fussy or very organised. It is not uncommon for someone who likes order to describe themselves as “a bit OCD”. This doesn’t recognise the challenges for people who live with OCD, who get no pleasure from their repeated actions and rituals. 

People with OCD experience a lot of distress and there is a significant impact on their day-to-day functioning. OCD disrupts people's lives in a most distressing way.

About 1 in 100 people develop OCD. It can affect anyone of any age and usually starts in childhood. It is diagnosed when you have recurrent and persistent thoughts, urges or impulses that are intrusive, unwanted and cause you distress. These thoughts and images are called obsessions. They can include themes of disaster, health and hygiene, dirt, sex, violence, religious and other taboos and self-worth. 

To try and feel better, you may feel compelled to deal with the thought, images or actions by doing something that you hope will prevent the situation you are dreading. This may be a physical or mental activity, and it is aimed at reducing anxiety or distress. These actions are known as compulsions.

Obsessive thoughts can be quite overwhelming, while compulsions can take up hours of your day and to others usually seem excessive or a little strange. 

Understanding obsessions

Most people who live with OCD are aware that the obsessions are products of their own mind, just like other thoughts, images and impulses. However, obsessions are much harder to control. 

The link between the obsessional thought and the compulsion can be quite strange. It can revolve around your self-worth and this can lead to significant distress.

The overwhelming nature of obsessions mean that trying to stop them can lead to self-doubt and cause more distress.

Understanding compulsions

Compulsions are usually, but not always, linked directly to the obsessional thoughts. They can include repetitive behaviours such as cleaning, checking, counting or praying, but can also include mental acts, such as repeating words or saying things to yourself about your self-worth. 

Performing the compulsion temporarily relieves the anxiety and distress caused by the thoughts. For example, obsessional thoughts about your hands being dirty lead you to feel anxious about catching a disease. This leads to repeatedly and excessively washing your hands. 

When you perform the compulsive action you feel a little better initially. But then the anxiety returns, and as time passes, doing the compulsion has less effect on it. This can lead to more and more compulsive behaviour in an attempt to control the rising level of anxiety. 

Some people experience OCD as a constant in their lives, but it is usually worse during times of stress and increased anxiety and uncertainty. This means that the symptoms can get better or worse over time.

You might notice yourself doing the following:

  • having constant intrusive, unwanted thoughts or mental images
  • washing your hands more often than is necessary or washing them for longer than necessary or using more soap than is necessary
  • cleaning your clothes, house or belongings more than is necessary or usual
  • putting things in a particular order
  • counting, repeating words, tapping, praying, having negative thoughts about the type of person you are
  • checking things – door locks, appliances, taps
  • feeling you have to do things over and over again to make sure they are as you expect them to be
  • constantly asking people for reassurance
  • having routines and rituals that you have to follow every day or under certain circumstances
  • being aware that your thoughts are irrational but being unable to stop the thinking.  

The exact cause of OCD is unknown. There is some evidence that OCD runs in families, but more research needs to be done in this area.

Many people who live with OCD also struggle with other conditions such as anxiety and depression. OCD is driven by the anxiety that comes with obsessions and compulsions. This anxiety can become extremely severe and is typically more difficult to manage when you are stressed and your levels of anxiety increase.

The energy used in trying to manage OCD can affect your sleep and have an impact on your mood. Feeling anxious and even having panic attacks are not uncommon experiences for people living with OCD. Feeling depressed is not uncommon and this might be as a result of getting worn down by the OCD or it might be contributing to some of the obsessions. 

Some people report suicidal thinking, particularly when their OCD is severe, untreated and lasts for a long time. Some people may try to reduce their symptoms with alcohol or substance use and this can lead to problems of addiction. 

Some people take a long time to seek treatment for OCD. This can be because they think that the discomfort or distress they feel is somewhat normal. They often feel embarrassment or shame for having particular thoughts and feeling compelled to perform specific acts. 

OCD can be treated. There are a range of treatments available. The first step is to see your doctor, who can discuss with you the options available.  These options may include a referral to a mental health specialist for talking therapy or medication to help you manage the obsessive thoughts and heightened anxiety you may feel. 


A variety of medicines have been helpful in the management of OCD. Selective serotonin reuptake inhibitors (SSRIs) are the most common medicines used for the treatment of OCD. SSRIs are also used to treat generalised anxiety and depression but may be prescribed at a higher dose for OCD.

After a number of weeks, you should begin to notice that you are having fewer intrusive thoughts, improved mood, reduced anxiety and an ability to begin tackling your compulsions through talk therapy.

Talking therapy 

Cognitive behavioural therapy (CBT) examines how you think, act and behave. The CBT approach to OCD proposes that obsessional thoughts continue because you can't stop or ignore them easily. It is difficult to stop or ignore the thoughts, but you do have some choice around how you respond to your thoughts.

Compulsions aim to relieve the anxiety produced by obsessive thoughts. Compulsive rituals, such as hand-washing after obsessive fear of contamination, produce only temporary relief before the anxiety builds up again. Each time the compulsion is repeated in response to the mounting anxiety, it strengthens the cycle. 

CBT treatment often includes exposure and response prevention(external link), which helps you to break the cycle and reduce the anxiety and need to perform the compulsive acts.

The treatment starts with a list of activities that make you anxious. You order them on a scale, from easiest to most difficult. Then, starting at the easiest activity, you do it, with the help of your therapist. While you're doing it, your psychologist will encourage you to experience the anxiety without performing a compulsion and to wait for your anxiety level to slowly drop. You repeat the activity until you become used to it. 

Learning to recognise which thoughts and feelings are fuelled by anxiety and OCD helps you make better choices about how you wish to respond to certain situations.

Once you begin to recover, there are things you can do to help yourself.

  • Eat healthily, do some exercise, develop good sleep habits and limit alcohol and caffeine.
  • Don't smoke.
  • Continue to challenge yourself by facing situations that make you anxious.
  • Find fun activities to fill in your extra time.
  • Join a support group in-person or online.
  • Be aware of the signs of depression.
  • OCD symptoms can come back, so have a plan ready so you can act as soon as you notice yourself becoming unwell. 

Perinatal OCD – new baby, distressing repetitive thoughts(external link) Perinatal Anxiety & Depression Aotearoa, NZ, 2020
Obsessive compulsive disorder(external link) Mental Health Foundation, NZ
Obsessive compulsive disorder(external link) Your Health in Mind, The Royal Australian and NZ College of Psychiatrists
Self-care for obsessive compulsive disorder(external link) Mind, UK
OCD challenge(external link) A free online course to help you challenge your OCD and take back your life.
OCD UK(external link) An organisation run by and for people with lived experience of OCD providing information and resources.


Obsessive compulsive disorder [PDF, 1 MB] Mental Health Advocacy and Peer Support Trust Canterbury, NZ, 2012

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Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.

Reviewed by: Ashley Macpherson, Clinical Psychologist

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