Obsessive-compulsive disorder (OCD)
Explains obsessive-compulsive disorder (OCD), including possible causes and how you can access treatment and support. Includes tips for helping yourself, and guidance for friends and family.
What are the symptoms of OCD?
This page covers:
What are intrusive thoughts?
An intrusive thought is an unwanted thought that pops into your mind. You could experience the thought as a:
- Feeling or sensation
- Memory
- Urge
- Mental picture
It may be triggered by something else. Or it might come into your mind for no obvious reason.
Intrusive thoughts are very common. It's estimated that we have thousands of thoughts each day. Because we have so many different thoughts, some of them will be random, meaningless or confusing.
Sometimes intrusive thoughts may feel scary, shameful or offensive. They might go against our values or beliefs. For example, you might get a thought about hurting someone. This could feel shocking and disturbing to you.
We can't control or get rid of intrusive thoughts. But just because a thought comes into your mind, it doesn't mean you agree with it or that it's true.
For those of us with OCD, intrusive thoughts can become obsessions. And the things we do to try to get rid of intrusive thoughts can become compulsions.
You can read more about coping with intrusive thoughts on our self-care for OCD page.
Everyone has intrusive thoughts – they often pop into your mind and then disappear. But in the minds of those of us with OCD, they ruminate endlessly and, as a result, we believe it says something about who we are.
What are obsessions?
Obsessions are when our intrusive thoughts are very hard to manage. They make us feel very distressed and have a negative impact on our daily life. Our worries and doubts may feel stuck in our mind. We may worry about what they mean or why they won't go away.
You might feel you can't share them with others or that there's something wrong with you that you have to hide. You might feel shocked or distressed that you're capable of having such thoughts.
I get unwanted thoughts all through the day, which is very distressing and affects my ability to interact with others and concentrate on my studies.
What are compulsions?
Compulsions are repetitive things that you feel you have to do to reduce the distress or uncertainty caused by obsessions.
You might feel like you have to continue doing the compulsion until your distress or doubt goes away and things feel right again. You might know that it doesn't make sense to carry out a compulsion. But you still feel unable to resist doing it.
Compulsions might make you feel better at first. But you may find the more you do a compulsion, the stronger the urge is to do it again. This can increase obsessions and distress in the long-term and can lead to an unhelpful cycle of thoughts and behaviours.
Compulsions can feel very time-consuming, tiring and overwhelming. They may stop you being able to go about your daily life or do the things you want to do.
Compulsions can:
- Be things you do physically
- Be things you do in your head, such as rumination. When compulsions are internal and don’t involve physically doing something, some people refer to this to as Pure O
- Involve a number, such as feeling like you have to complete a compulsion a specific number of times without interruption
- Involve someone else, such as asking others for reassurance
Without realising it, I started doing rituals to try to get rid of these thoughts - my 'compulsions'. I had no awareness of what was going on.
Types and examples of compulsions
Anything can become compulsive. If you can do, say, or think it, it can become compulsive. Sometimes the compulsion will be clearly linked to the thing you're worried about. And sometimes it will be less clear. The types of compulsions you do may change over time.
Some examples of compulsions are listed below. Doing some of these things doesn't mean you have OCD. And you may have OCD but have different compulsions to those listed here. You can read our information on identifying your compulsions.
Rituals
- Washing your hands, body or things around you a lot
- Touching things in a particular order or at a certain time
- Arranging objects in a particular way
- Saying things again and again
Checking
You might repetitively check:
- Doors and windows to make sure they are locked
- Your body or clothes for contamination
- Your body to see how it responds to intrusive thoughts
- Your memory to make sure an intrusive thought didn't actually happen
- Your route to make sure you didn't cause an accident when you travelled somewhere
- Your phone or computer to see if you've sent something offensive or embarrassing
Correcting thoughts
- Repeating a word, name or phrase in your head or out loud
- Counting to a certain number
- Trying to replace an intrusive thought with a different image
- Trying to replace a negative feeling with a positive one
- Doing something again and again until it feels 'right'
Reassurance
- Repeatedly asking other people to tell you that everything is alright
- Saying or doing things to test other people's reactions
- Repeatedly apologising to people
- Confessing your intrusive thoughts to people and asking what they mean
- Constantly telling yourself that your intrusive thoughts aren't true
Rumination
- Thinking about the same thing again and again
- Trying to solve or fix your intrusive thoughts by thinking about what they mean
- Doing research on the internet about your obsessions
Avoidance
- Avoiding situations or people that make you anxious. For example, stopping driving to cope with intrusive thoughts about running someone over
- Avoiding access to things. For example, removing anything from your home that could hurt someone
- Delaying or putting things off (procrastination) to avoid feeling anxious or uncomfortable
Are there different types of OCD?
Sometimes OCD is separated into 'types'. For example, you may hear people talking about 'contamination OCD' to mean obsessions and compulsions about dirt or germs.
Some of us find it helpful to label our OCD in this way. It might make it easier to make sense of our OCD or to find others with similar experiences.
Or we might find this type of labelling unhelpful. We may have obsessions and compulsions that don’t fit into a common 'type'. Or labelling our OCD as a particular type might make it harder to notice new obsessions or compulsions that don't fit this type.
You may prefer to use the word 'themes' to describe the different topics of your obsessions and compulsions. You may have one theme, or lots of different ones. They may change or come and go over time. Some themes may bother you more than others.
Some doctors or therapists may talk about different types of OCD. But different types of OCD are not separate diagnoses.
That's the important thing to remember about OCD; it changes and develops with us. It'll always try to capture what we feel most insecure and vulnerable about
OCD can attach to anything. If you can think of it, it can become an obsession or an OCD theme.
Some themes are more common than others. But if you have a theme that's less common, this doesn't mean that your OCD isn't real. Or that you deserve support less than anyone else.
Some examples of OCD themes or types include:
Harming someone or violence
- Worrying you've already harmed someone by not being careful enough. For example, that you've knocked someone over in your car.
- Worrying you're going to harm someone because you'll lose control. For example, that you'll push someone in front of a train or stab them.
- Violent intrusive thoughts or images of yourself doing something violent or abusive. These thoughts might make you worry that you're a dangerous person.
Imagine the utter horror of taking someone's life. Now imagine having that thought over ten times a day - and not being able to get rid of it
Relationships
- Worrying about your relationships. For example, having doubts about whether a relationship is right. Or worrying people may dislike you or leave you. This can be about anyone in your life, including your partners, friends, family members or strangers.
- Sexual intrusive thoughts or images. These could be related to children, family members or to sexually aggressive behaviour. You might worry that you could be a paedophile or a rapist. Or that you're sexually attracted to someone in your family.
Contamination
- Contamination, for example by dirt, germs or faeces. You might worry that you've been contaminated and that you're spreading the contamination, or that other people are. Or you might worry that you have a disease, or might get one.
- Mental contamination. You might experience feelings of dirtiness, discomfort or feeling incomplete. These feelings may be triggered by a certain person, place or object. They may also be triggered by your own thoughts, images or memories.
Actions such as touching an item belonging to someone else would lead to obsessive thoughts of myself coming to harm
Your identity
- Worries or doubts about your identity. For example, having obsessions or compulsions about your sexuality or gender identity. Or having constant doubts about your beliefs or values.
- Worries about whether you're a bad person. For example, constantly checking whether you've thought something bad, worrying you may say something offensive or constantly thinking about things you regret from the past.
- Obsessions relating to your body. This could include constantly worrying about how you look or feel. Or feeling very conscious of physical sensations like blinking or swallowing.
When thoughts are intrusive, when they're negative, they can kind of feel like, does this make me a bad person?... Does the nature of these thoughts make me vile?
The future
- Worries about the future. For example, getting intrusive thoughts about you or a loved one getting ill or hurt. Or something bad happening in the world.
- Fear that something bad will happen if everything isn't 'right'. For example, if things are not clean, in order or symmetrical.
The worst things you could imagine happening to your baby were in my head. For days I couldn't sleep, I couldn't eat, I barely functioned.
How can I be sure I have OCD?
It's understandable to want to be sure about whether you have OCD or not. Especially if it's helped you get the support and understanding that you need. Or if it helps you feel less alone or ashamed about your intrusive thoughts.
But for those of us with OCD, our need for certainty can make our symptoms worse. It's very common for those of us with OCD to worry about whether we really have OCD. This is sometimes called 'meta OCD'.
You might have intrusive worries or doubts about whether your OCD is real or serious enough. You might worry that you’ve lied to people or wasted people's time by seeking support. Or you might worry that you're using OCD to cover up the fact that your intrusive thoughts are true.
You may then use compulsions to try to cope with these worries. This could include ruminating about whether you have OCD, or seeking reassurance from others. Or you might research OCD on the internet, or stop your treatment to test whether your symptoms get worse. This can have a big impact on recovery.
If you're struggling with this, try to remember that we can never be certain about anything. This includes whether we have OCD or not. And try to resist compulsions if you can.
Our pages on treatment and self-care have information on seeking support and managing symptoms.
What is 'pure O'?
Pure O stands for 'purely obsessional'. People sometimes use this phrase to describe a type of OCD where they experience distressing intrusive thoughts. But they don't have any external signs of compulsions, such as checking or washing physical things. The name is slightly misleading as it suggests that there are no compulsions at all.
With pure O, you still experience compulsions. But rather than things you do physically, they will be things you do in your mind. Because they're sometimes not as obvious as physical compulsions, they can be harder to spot. Or it can be hard to define exactly what these compulsions are.
These are some examples of mental or internal compulsions:
- Checking how you feel - for example, you might check to see if you are still in love with your partner
- Checking bodily sensations - for example, you might check to see if you were aroused by an intrusive thought
- Checking how you feel about a thought - for example, you might check whether you're still upset by the thought
- Repeating phrases or numbers in your head
- Checking if you still have a thought - for example, first thing in the morning
- Thinking about a problem over and over
- Reassuring yourself over and over again that you're a good person or that your thoughts aren't true
Getting ready involves so much hand washing and so many mental rituals. Sometimes, I feel like staying in bed and avoiding the day.
This information was published in October 2023. We will revise it in 2026.
References and bibliography available on request.
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