What is obsessive compulsive disorder (OCD)?

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Obsessive‑compulsive disorder is a disease characterised by involuntary thoughts, mental images or urges (obsessions) that impel the individual to perform an action repeatedly (compulsions) to alleviate the distress they cause. Although everybody has these thoughts, images and urges, the differentiating feature is whether they interfere in everyday life and take up a lot of time.

Obsessive Compulsive Disorder explained in first person

Professionals and patients explain how you live with the disease
To diagnose obsessive compulsive disorder, these obsessions and compulsions have to cause high levels of anxiety and, furthermore, a notable disfunction. In other words, they have to take up a lot of our time throughout the day.
Be patient and understand what OCD really is. Don't judge. Understanding what it consists on, how it works, what the symptoms are and how the person suffering from it might feel.

Someone with obsessive‑compulsive disorder (OCD) has obsessions and compulsions that cause them significant difficulties in everyday life.

Obsessions are repetitive and uncontrollable thoughts, mental images or urges that cause negative feelings in the individual (anxiety, guilt, etc.) and do not form part of their normal worries. For example, common obsessions include the idea that the subject is dirty or contaminated; the image that something terrible is going to occur (e.g., their home is about to burn down); or the urge to behave immorally (e.g., to attack someone inadvertently).

Compulsions are behaviours or mental acts the person routinely performs to eradicate the distress caused by the obsessions. Compulsions are also known as rituals. Examples include repetitive washing of a body part because the individual feels dirty; repeatedly checking the gas is turned off or the front door before leaving the house; or mentally repeating a phrase to calm oneself down.

Most people with OCD suffer both obsessions and compulsions, although some only experience obsessions. In childhood and adolescence, compulsions tend to appear before obsessions, and they may sometimes develop while the individual is yet unable to explain the obsession.

Adults with OCD are normally aware of the fact that their obsessions and/or compulsions are irrational (they are not logical) or excessive, but they cannot stop thinking about them or doing them, whereas children and adolescents usually find it hard to recognise them.

What is NOT Obsessive Compulsive Disorder?

Man and woman

Everyone experiences obsessions/compulsions. Virtually everyone has an obsession or acts out a compulsion in their day‑to‑day life, but in people with OCD these obsessions and/or compulsions become a cause for significant difficulties (e.g., at school, at work, in personal relationships, etc.) and occupy a lot of time (normally, more than an hour each day). People are only diagnosed with OCD when these difficulties arise.

Stress and occupational anxiety for a long time

“Normal” worries about real‑life problems are not obsessions, for example, regarding work or financial matters. OCD must be diagnosed by an experienced mental health professional.

Person surrounded by many messages

An obsessive personality is not the same as OCD. Some people are very inflexible, perfectionists, overly focused on their work, etc., to such a point that the nature of their character causes them difficulties. These individuals are said to have an obsessive personality (or, in some cases, they have obsessive‑compulsive personality disorder). However, most people with OCD do not have obsessive‑compulsive personality disorder, in the same way that most people with obsessive‑compulsive personality disorder do not have OCD.

How many people does it affect?

OCD is a common disorder; it affects approximately 1 in every 50 people. It has been observed in all cultures.

Although it can appear at practically any age, an individual is most likely to develop OCD one around 10 years old, and another at the beginning of the 20s..

Children, even very young ones, can develop OCD. It is important to be aware that children sometimes have obsessions or compulsions and that they are usually short‑lived, normal at certain ages and disappear after a few weeks or months. However, if these obsessions or compulsions continue for longer periods or cause difficulties, then an experienced professional must be consulted to determine whether the child has OCD.

Some people have obsessions or compulsions throughout much of their life, but they do not cause them difficulties, so they are not considered to have OCD.

Substantiated information by:

Luisa Lázaro García
Miquel Àngel Fullana Rivas

Published: 7 February 2019
Updated: 7 February 2019

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