Obsessive-compulsive disorder (OCD)

About OCD

If you have OCD, you will have obsessions (intrusive, recurrent, and distressing thoughts, sensations, urges or images) that take the place of your everyday thoughts. You’re also likely to have compulsions (actions) that are used as a way of setting right or cancelling out the obsessive thought. Compulsions are things you feel compelled to do even though you may know the behaviour does not make sense. Compulsions are typically done to reduce the fear or distress associated with obsessive thoughts.

Although everyone will have worrying thoughts occasionally, such as a concern over cleanliness or fear that they have left the oven on, these thoughts usually appear briefly, go away again easily and don’t cause any further problems. With OCD, you will have repetitive, worrying thoughts that often prevent you thinking about anything else. In addition, as a way to combat these obsessive thoughts, you will feel compelled to carry out repetitive behaviours. This could be physically checking and rechecking something, or it may be that you have to repeat in your mind a particular phrase or count to a certain number again and again.

Symptoms of OCD

If you have OCD, you will have your own experience of what obsessions and compulsions you have, which will be different to other people with OCD. However, there are some common themes that many people with OCD find they obsess about. The main features of obsessions are that they happen frequently, cause you anxiety, and don’t go away easily. Some of the main obsession themes are listed below. 

  • Contamination obsessions – fearing dirt and germs.
  • Aggressive obsessions – fearing doing harm to yourself or others.
  • Sexual obsessions – having forbidden, upsetting thoughts.
  • Health-related obsessions – such as concern that you have a serious illness, without having any of the symptoms.
  • Magical obsessions – such as believing in lucky or unlucky numbers.
  • Religious or moral obsessions – having religious or anti-religious thoughts.
  • Hoarding obsessions – worrying about throwing away useless or worn out items.

There are compulsions that you may feel you have to carry out whenever an obsessive thought arises. Examples are listed below.

  • Excessive hand washing.
  • Checking something again and again, such as making sure a door is locked.
  • Repeating an action, such as only walking through doorways in a particular way.
  • Praying, saying a phrase over and over or counting in your mind.
  • Ordering or arranging items in a certain way.
  • Hoarding or collecting things that have no use.
  • Excessively asking others for reassurance – this happens more in children who have OCD.

Often the compulsion you carry out is linked to the obsession you have. So, if you obsess about germs and cleanliness, you may feel compelled to wash your hands repeatedly and in a certain way. However, this isn’t always the case and some compulsions may appear to have no relation to the obsession that sets them off. Although the action will push away the obsessive thought for a while, with OCD the thoughts return and get more difficult to get rid of each time. Therefore, more compulsive behaviour builds up and you spend more time doing these actions.

OCD can lead to you spending a lot of time carrying out compulsive behaviour that gets in the way of doing everyday tasks. You may also go to great lengths to avoid situations that could start an obsessive thought pattern.

Causes of OCD

It’s not fully understood why OCD develops, although there are a number of theories that try to explain it. It’s likely that it begins as a result of a number of factors.

You may find that a stressful event, such as the death of a loved one, the birth of a baby or starting a new job, triggers your OCD or makes it worse. It may be that you had a childhood trauma that set off the OCD cycles. It’s also possible that if one of your parents showed signs of OCD, this may have been passed on to you.

The condition may be the result of different levels of certain brain chemicals such as serotonin. Researchers have found that for some people with OCD there appears to be a link between this chemical and the severity of OCD symptoms. You may find medicines helpful to bring your symptoms under control.

In some children, OCD develops after infection with a type of bacteria called Streptococcus.

Diagnosis of OCD

If you think you may have OCD and this is affecting how you live your life, see your GP. He or she will ask about your symptoms. Your GP may also ask you about your medical history. It’s important to be as open and honest as you can with your GP about any obsessions and compulsions because this will help him or her to make the right diagnosis and recommend the right treatment.

You may be referred to a psychiatrist (a doctor who specialises in mental health), psychologist (a health professional who specialises in emotional and behavioural problems) or other mental health professional for further treatment.

Treatment of OCD


You may find that talking to other people who have similar symptoms helps you to understand your condition better. There are a number of charities that can put you in touch with self-help groups. There are also CDs, DVDs and books that you might find useful.

You could try writing down your obsessive thoughts. This may make you feel more in control of them and allow you to dismiss them more easily.

Don’t use illegal drugs or alcohol to alleviate anxiety or to push away your obsessive thoughts. Using these can have serious consequences for your physical and mental health.

You could learn a relaxation technique to help you to deal with anxiety better and to cope with stressful situations. This might include breathing exercises or exercises designed to help you relax your muscles.

Talking therapies

You may be offered a therapy called cognitive behavioural therapy (CBT) that can help you to manage your OCD symptoms. CBT can help you to change how you think ('cognition') and what you do ('behaviour'). If your symptoms of OCD are mild and not affecting your life too much, you may be offered a short course of one-to-one CBT, or sessions by telephone, or group sessions. This will usually be up to 10 hours of sessions with a CBT practitioner. If your symptoms are affecting your life more seriously, you may be offered more one-to-one sessions of CBT.

One of the main forms of CBT that is effective in treating OCD is exposure and response prevention (ERP). This is used as a way to stop your obsessions and compulsions from strengthening each other. It has been found that if you stay in a stressful situation for long enough you will get used to it and your anxiety goes away. With ERP your CBT practitioner will help you to face your fears (exposure) but you will stop yourself from carrying out your usual compulsion (response prevention) and then wait for your anxiety to drop.

For example, you might have a compulsion to wash your hands immediately and thoroughly every time you touch a door handle. In the process of ERP you would break this cycle by not washing your hands straight away. You will find that nothing bad happens and gradually you will feel less anxious about it. Once you have overcome an obsession that you find makes you less anxious you would move onto one that makes you more anxious and face it in the same way.

You may find this process is distressing to begin with so it’s helpful to work with a CBT practitioner. He or she will probably ask you to do homework between each session. This will involve continuing to face your fears and overcoming the compulsions. Completing the homework can have a positive effect on how quickly you overcome your obsessions and compulsions. 


If you find that your symptoms don’t improve enough with a therapy such as CBT, you may be offered medicines such as certain antidepressants (ie fluoxetine). These medicines affect the chemicals (particularly serotonin) in your brain and help to ease OCD symptoms or make it easier for you to deal with them. This is particularly helpful if you find your symptoms are worse when you feel depressed.

You may be offered another medicine called clomipramine that works in a different way, which might work better for you.

You may find that a combination of CBT and one of these medicines helps to make your OCD easier to cope with.

Living with someone who has OCD

Living with someone who has OCD can be difficult. Learning more about OCD may help you understand the person with OCD better. You may find it’s helpful to accept the obsessions and compulsions that the person has, but without encouraging them. For example, if the person washes his or her hands repeatedly, there is no need for you to do this as well, even if you can see it makes them feel uncomfortable. Encourage the person to seek help from his or her GP or organisations that can help with mental health issues. 

How will my GP know if I have obsessive-compulsive disorder (OCD)?


Your GP will ask you some questions about your symptoms and how they are affecting your everyday life. From your answers he or she will be able to make a diagnosis and assess how any obsessions or compulsions are impacting on your life. He or she can then consider if treatment is needed.


Your GP will ask you direct and specific questions about your daily life that will help him or her understand whether or not you have OCD. Typical questions might include “Do you wash or clean a lot?”, “Do you spend a lot of time checking things?” and “Is there any thought that keeps bothering you that you would like to get rid of, but can’t?”. Although you may feel embarrassed to talk about your symptoms, or ashamed about admitting to obsessive thoughts and compulsive actions, you need to try to be open about how these are affecting your life, so that you can be treated effectively.

Do the medicines that can help to control OCD have any side-effects?


Yes, the medicines that are often prescribed to help with OCD can have side-effects.


A type of antidepressant medicine called selective serotonin re-uptake inhibitors, for example fluoxetine, is often prescribed to control OCD symptoms. You may find you get side-effects such as feeling sick, headaches, problems sleeping, stomach upsets and increased anxiety. These medicines may also cause sexual problems. Most people find that these side-effects settle down after a few weeks of taking the medicine.

You may be prescribed a different medicine called clomipramine. You may have side-effects that include a dry mouth, blurred vision, constipation, drowsiness and dizziness.

Your medication can take up to 12 weeks to start working. It's important that you don't suddenly stop taking it without speaking to your GP. If you stop, or forget to take your medication, you may get withdrawal symptoms such as headaches, dizziness, feeling sick and anxiety.

Always ask your GP for advice and read the patient information leaflet that comes with your medicine.

Is body dysmorphic disorder the same as OCD?


Body dysmorphic disorder (BDD) and OCD are separate conditions, but they do have some similarities.


BDD is a condition that causes you to spend a lot of time being concerned about how you look. If you have BDD, you will usually be worried that you have one or more physical flaws. Most of us worry about our appearance at some time, but if you have BDD, your preoccupation with your appearance can make you feel distressed and may affect how you live your day-to-day life.

The similarity with OCD is that if you have BDD, you may feel that you need to repeat certain acts. These acts may include frequently checking how you look or asking for reassurance about your appearance. Other examples include repeatedly applying your make-up or picking your skin to make it smooth. If you have BDD, you may feel that you can't go out in public unless you have hidden your 'flaws' with make-up or clothing.

The treatment for BDD is very similar to that for OCD. You will usually be offered cognitive behavioural therapy (CBT). If this doesn't help, your GP may prescribe medication to help control your symptoms.

Does OCD occur on its own or is it always accompanied by other mental health problems?


OCD does occur on its own but there may be an increased risk of other mental health problems, particularly depression, if you already have OCD.


One reason why having OCD may mean you have an increased risk of also getting depression is that having the condition can be very upsetting. OCD can interfere with work and family life and prevent you from being able to do things that you would like to. If your OCD becomes severe, you may find it more difficult to leave the house, have relationships or carry out simple tasks such as throwing away items of rubbish or that have no use. OCD can be difficult for other people to understand and you may feel unable to talk about it.

However, the risk of you also having mental health problems other than depression is low.