Obsessive compulsive disorder (OCD) is a mental health condition where a person has obsessive thoughts and compulsive activity.
An obsession is an unwanted and unpleasant thought, image or urge that repeatedly enters a person's mind, causing feelings of anxiety, disgust or unease.
A compulsion is a repetitive behaviour or mental act that someone feels they need to carry out to try to temporarily relieve the unpleasant feelings brought on by the obsessive thought.
For example, someone with a fear of their house being burgled may feel they need to check all the windows and doors are locked several times before they can leave the house.
OCD symptoms can range from mild to severe. Some people with OCD may spend an hour or so a day engaged in obsessive-compulsive thinking and behaviour, but for others the condition can completely take over their life.
Read more about the symptoms of OCD.
What causes OCD?
It's not clear exactly what causes OCD, although a number of factors have been suggested.
In some cases the condition may run in families, and may be linked to certain inherited genes that affect the brain's development.
Brain imaging studies have shown the brains of some people with OCD can be different from the brains of people who do not have the condition.
For example, there may be increased activity in certain areas of the brain, particularly those that deal with strong emotions and the responses to them.
Studies have also shown people with OCD have an imbalance of serotonin in their brain. Serotonin is a chemical the brain uses to transmit information from one brain cell to another.
Read more about the causes of OCD.
Who is affected?
It's estimated around 12 in every 1,000 people in the UK are affected by the condition. This equates to almost 750,000 people.
OCD affects men, women and children. The condition typically first starts to significantly interfere with a person's life during early adulthood, although problems can develop at any age.
People with OCD are often reluctant to seek help because they feel ashamed or embarrassed.
However, if you have OCD, there is nothing to feel ashamed or embarrassed about. It is a long-term health condition like diabetes or asthma, and it is not your fault you have it.
Seeking help is important because it is unlikely your symptoms will improve if left untreated, and they may get worse.
You should visit your GP if you think you may have OCD. Initially, they will probably ask a number of questions about your symptoms and how they affect you.
If your GP suspects OCD, you may need to be referred to a specialist for an assessment and appropriate treatment.
Read more about diagnosing OCD.
How OCD is treated
With treatment, the outlook for OCD is good. Many people will eventually be cured of their OCD, or their symptoms will at least be reduced enough that they can enjoy a good quality of life.
The main treatments for OCD are:
cognitive behavioural therapy (CBT)
– involving a therapy known as graded exposure with response prevention (ERP), which encourages you to face your fear and let the obsessive thoughts occur without "neutralising" them with compulsions
selective serotonin reuptake inhibitors (SSRIs) – this medication can help reduce your symptoms by altering the balance of chemicals in your brain
If these treatments aren't effective or your condition is particularly severe, you may need to be referred to a specialist mental health service for treatment.
Read more about treating OCD.
Last updated: 17 September 2015
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