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About OCD


  1. What is obsessive-compulsive disorder (OCD)?
  2. Obsessional thoughts
  3. Compulsions
  4. Some common obsessive thoughts
  5. Some common compulsive behaviours
  6. What causes OCD?
  7. The OCD cycle
  8. Things that don't usually help
  9. Page 2: OCD Self Help

What is obsessive-compulsive disorder (OCD)?

OCD is characterised by intrusive, unwanted thoughts and by compulsive actions - for example cleaning, checking, counting or hoarding. The sufferer can become tormented by a pattern of thoughts and behaviours that can be very time consuming and difficult to stop.

An obsession is a persistent, unwanted and uncontrollable thought, image, impulse, fear, doubt or urge that repeatedly enters the mind. A compulsion is a repetitive behaviour or psychological act that a person feels driven to do, even against their will. Obsessions and compulsion occur together in OCD.

Amongst the top 10 'most debilitating illnesses' identified by the World Health Organisation (WHO), obsessive-compulsive disorder is thought to affect two to three percent (2 - 3%) of the UK population. In men, OCD symptoms typically start during adolescence. In women they tend to start a little later, usually in the early 20's. Symptoms can, however, start at any time, including during childhood.

The symptoms of OCD can range from mild to very severe. Some people with OCD will spend less than an hour each day engaged in obsessive-compulsive thinking and behaviour, while for others the symptoms can completely dominate their lives. Sufferers may try to keep their compulsive behaviours hidden from others rather than risk shame or embarrassment.

Obsessional thoughts

Obsessional thoughts are repetitive, intrusive and involuntarily. They may be horrific and repugnant to the person having them, who recognises these thoughts are their own, i.e. that their thoughts are not the product of some external person, agency or force.

The intrusive thoughts in OCD are often the most upsetting they could possibly be; they may involve some crime, humiliation or sex act repellent to the sufferer. They often cause a great deal of anguish.

Ironically the likelihood that people suffering from intrusive thoughts will act on those thoughts is very low; people who feel intense guilt, anxiety and shame over 'bad thoughts' are very different from the type of person who actually acts on their thoughts.


Compulsions are often attempts to stop thoughts from intruding, or to protect against some horrible event. Compulsions are something we actually do, either visibly (overt compulsions), such as washing and cleaning, or they may be internal and unseen - such as counting or repeating something inside over and over (covert compulsions).

Overt compulsions typically include checking, washing, hoarding or repeated actions of some kind.

Covert compulsions involve carrying out some kind of repetitive thought. For example, a sufferer who feels compelled to silently repeat a string of words over and over again, like a prayer or mantra, on having a disturbing thought. Covert compulsions are carried out in the hope that they will somehow neutralise or 'get rid of' unwanted thoughts.

Sometimes compulsions can be relatively minor; they might be concealed and only known about by family and close friends. Severe compulsions can make it very hard to be in work, public places or take part in social relationships.

Unlike some forms of compulsive behaviour, for example addiction to drugs or gambling, a person with OCD gets no pleasure at all from their compulsive behaviour. It only serves to temporarily reduce tension or anxiety.

Avoidance is a common compulsive behaviour. The sufferer, in a bid to prevent distress and rituals, may go to great lengths to avoid the objects, places or people that trigger their obsessions.

OCD is 'ego dystonic', meaning that the disorder is incompatible with the sufferer's view of themselves. Because disorders that are ego dystonic contradict an individual's perception of his or herself, they often cause a great deal of distress. Sufferers know there's something wrong, and want to be free of the obsessions and compulsions.

Obsessive-Compulsive Personality Disorder (OCPD), on the other hand, is 'ego syntonic', meaning the individual accepts the symptoms of the disorder as being in accord with his or her self-image. A person with OCPD is likely to view their compulsive cleanliness as a 'necessary precaution', and so believe themselves to be justified in carrying out their compulsive rituals.

Ego syntonic disorders cause little or no distress. Persons suffering from OCD are often aware that their behaviour is not rational and are unhappy about their obsessions, but nevertheless feel compelled to perform them. Persons with OCPD are not aware that there's anything wrong; they will readily explain why their actions are rational and it is often very difficult to convince them otherwise.

Some common obsessive thoughts

  • Worrying that you, or your environment, is dirty or contaminated perhaps by chemicals, bodily fluids, dirt, germs or pests
  • Worrying about catching some dangerous or unpleasant disease
  • Feeling things needs to be arranged in some kind of order
  • Worrying about causing harm to yourself or to other people
  • Intrusive, unpleasant sexual thoughts and feelings
  • Intrusive doubts about your own sexuality or sexual preferences
  • Intrusive fear of acting inappropriately towards children
  • Horrific, intrusive violent thoughts
  • Worrying that something terrible will happen unless you check, or repeatedly perform some ritual
  • Worrying about causing an accident or harm to someone
  • Worrying that you might scream or shout out obscenities in public

Some common compulsive behaviours

  • Excessive personal washing
  • Excessive cleaning of the environment
  • Checking that things are arranged in some kind of order or alignment
  • Repetitive thoughts, e.g. counting or repeating a phrase
  • Avoiding certain places, people or situations in an effort to avoid intrusive thoughts
  • Repeated checking of switches, handles, taps, locks etc. Checking can be for a set number of times and may take hours
  • Saying specific words in response to other words
  • Removing or hiding knives, due to the thought of accidentally hurting someone
  • Checking ones emails, cards or letters over and over again before sending them

What causes OCD?

We don't know for sure, but it seems some people have a genetic predisposition to developing OCD, which can be 'triggered' by things that happen in their lives.

  • Genes - OCD is sometimes inherited so can run in families. Some people seem to have a 'sticky' brain, meaning they tend to dwell on thoughts longer than others.
  • Stress - Stressful life events, particularly those which make us feel 'out of control' seem to have preceded OCD in about one out of three cases.
  • Life changes - Times where someone suddenly has to take on more responsibilities - for example, puberty, the birth of a child or a new job can make us more at risk of developing OCD.
  • Brain changes - We don't know for certain, but if you have the symptoms of OCD for more than a short time, researchers think that an imbalance of a chemical called serotonin develops in the brain.
  • Personality traits - If you are a neat, careful person with high standards you may be more likely to develop OCD. These qualities are normally helpful but, for a small minority of people, they can develop into OCD if they become too extreme.
  • Ways of thinking - All of us have upsetting thoughts or images from time to time - 'what if I stepped out in front of that car?' or 'I might kill someone'. Mostly we dismiss these ideas. If we have especially high standards of morality and responsibility, we may feel that it's terrible to have these thoughts, and so become vigilant for their return - which makes it all the more likely that we will notice them again. Psychologically speaking, we tend to intensify the things we try to guard against.

The OCD cycle

OCD can be a vicious circle (figure 1). There's an initial trigger - maybe a thought, memory, emotion, physical sensation or a realisation about something in the environment. The trigger begins a cascade of intrusive, unpleasant thoughts, which result in distressing emotions - often fear or shame.

We begin a process of dealing with these thoughts and emotions (our compulsions), which take the form of a ritual or some form of behaviour that distracts or soothes us. The compulsions themselves may be supported by a system of beliefs that suggest we will be safe when we have reached a 'magic' number of repetitions, or performed a ritual 'perfectly enough', or when things are 'exactly right'.

Unfortunately, as our distress reduces, we assume that our compulsions have been effective, which makes it more likely we'll do them again in the future.

Sometimes our distress itself can be a trigger which keeps the OCD cycle going

Figure 1

Things that don't usually help

  • Trying to banish unpleasant thoughts from the mind tends to make the thoughts return. As an experiment, try not to think of a large colourful beach ball for the next few seconds - most people find it's hard to banish all thoughts of beach balls from the mind!
  • Rituals, checking, avoiding and seeking reassurance can make us feel a bit better for a while. However, every time we do them we strengthen the unhelpful idea that they stop bad things from happening - so we feel more pressure to do them again. It's very easy to get into a vicious circle.
  • Thinking neutralising thoughts - if we spend time 'neutralising' a negative thought with another thought (for example, counting to ten or reciting a prayer) we can come to depend on the ritual. The ritual may become more of a problem than the thought or the image it was meant to replace.