Obsessive-Compulsive Disorder (OCD): An Insight


Published: 24 November 2022

Obsessive-compulsive disorder (OCD) is a mental illness as per the Diagnostic and Statistical Manual of Mental Disorders DSM-5-TR (APA 2022).

OCD is estimated to affect about 3% of Australians in their lifetime - that’s more than 500,000 people (QBI 2017; Healthdirect 2020).

The primary features of OCD are the presence of obsessions, compulsions, or both. They are defined by the DSM-5 as:

  • Obsessions: Repetitive and relentless thoughts, impulses or urges that are unwanted and often intrusive. These thoughts cause anxiety and distress.
  • Compulsions: Repetitive behaviours (often the examples of handwashing and ordering are used) or mental activities such as praying, counting and/or repeating words silently. The individual will feel compelled to carry out these acts in an attempt to quell their obsessive thoughts.

(APA, as cited in Beyond OCD 2018a)

young girl with ocd
OCD is estimated to affect about 3% of Australians in their lifetime.

These obsessions and compulsions will be time-consuming, sometimes taking up more than an hour a day. They cause significant distress and either social or occupational impairment or hinder another important area of functionality (Beyond OCD 2018a). In very severe cases, OCD can cause a person to be housebound (Better Health Channel 2022).

OCD typically presents during childhood or adolescence, most people are diagnosed by the time they reach their late teens (SANE 2018).

It’s common for people who have OCD to also live with other mental health conditions such as an anxiety disorder (e.g. social anxiety or panic disorder) or depressive disorder (Healthdirect 2020).

People who have OCD often report feeling deep shame about their behaviours and compulsions. These feelings of shame can exacerbate the problem, and cause people to delay seeking help and treatment (Beyond Blue 2013).

OCD previously existed under ‘Anxiety Disorders’ in the earlier edition of the DSM (DSM-IV). Experts (controversially) argued for OCD to be grouped with loosely-related conditions under the new category ‘Obsessive-Compulsive and Related Disorders’ (now seen in the DSM-5) (OCD-UK n.d.).

The Difference Between OCD and OCPD

It is important to note that obsessive-compulsive disorder (OCD) is distinct from obsessive-compulsive personality disorder (OCPD).

The essential feature of OCPD is defined by the DSM-5 as:

‘A preoccupation with orderliness, perfectionism, and mental and interpersonal control, at the expense of flexibility, openness, and efficiency. This pattern begins in early adulthood and is present in a variety of contexts … Despite the similarity in names, OCD is usually easily distinguished from obsessive-compulsive personality disorder by the presence of true obsessions and compulsions in OCD.’

(APA 2013)

Causes of OCD

While it’s not known what exactly causes OCD, it’s generally thought to occur due to a combination of genetic factors, abnormalities of the brain, behavioural factors and environmental factors. Other reasons might be a family history of OCD, social factors and psychological factors (Beyond Blue 2013; Beyond OCD 2018b).

Symptoms of OCD


Obsessions are intrusive, unwanted and cause distress and anxiety. A person will not derive pleasure from them and they are not voluntary. A person will attempt to neutralise these through compulsions. Obsessions may include:

  • Repetitive or persistent thoughts or images, for example, a deep fear of contamination
  • Intrusive thoughts and images, for example, of a violent or frightening nature
  • Unwanted and distressing urges.

(APA, as cited in Beyond OCD 2018a; Better Health Channel 2022)


Compulsions are behaviours or mental acts intended to reduce anxiety and stress. Often, they are not linked with what they are designed to dull or prevent in a way that would be considered realistic, and/or they are clearly excessive. They may include:

  • Handwashing
  • Ordering
  • Checking
  • Praying
  • Counting
  • Repeating words (silently).

(APA, as cited in Beyond OCD 2018a)

Diagnosing OCD

A person seeks help for ocd
A health professional will investigate the presence of obsessions and compulsions.

A health professional will investigate the presence of obsessions (recurrent and relentless thoughts, urges or impulses) and compulsions (repetitive behaviours or mental acts). The likelihood of a diagnosis of OCD increases if:

  • These obsessions and compulsions are time-consuming or cause clinically significant distress or impairment
  • The symptoms cannot be attributed to another medical condition or to the psychological effects of a substance
  • The effects of the condition could not be more accurately explained by another mental disorder.

(APA, as cited in Beyond OCD 2018a)

Treatment for OCD

OCD is treatable. Seeking professional support and treatment is crucial to being able to start or resume a life that is not impeded by overwhelming anxiety and distress.

There are two main types of effective treatment for OCD: psychological treatment and treatment with medication (SANE 2018).

The primary treatment for OCD is cognitive behavioural therapy (CBT). It’s important for patients to find a cognitive behavioural therapist who is specifically trained and experienced in OCD (Beyond OCD 2018c).

CBT usually involves two kinds of evidence-based techniques:

  1. Exposure and response prevention therapy (ERP)
  2. Cognitive therapy (CT).

In ERP therapy, a therapist will gradually expose the person with OCD to the situations that trigger their obsessions and/or compulsions. The aim is that over time, the person will learn to respond differently to these triggers. Eventually, the frequency of compulsions and the intensity of obsessions will reduce (Beyond OCD 2018c).

In CT, a person will be encouraged to identify patterns of thought that create anxiety, distress or negative behaviour, and learn to modify them. CT helps a person to understand that their brain is sending false and unhelpful messages. They learn to recognise these messages and respond to them differently (Beyond OCD 2018c).

Medication can also be effective. Certain medications can help to restore the brain’s normal chemical balance, which may help to control obsessions and compulsions (SANE 2018).

A community support group may also be beneficial for someone living with OCD, as it can provide an environment in which people living with OCD and their families can meet to give and receive support. As well as accessing support, patients will be able to access information, self-help strategies, and coping strategies (SANE 2018).

A man recieves cupport for his OCD
Obsessions are intrusive, unwanted and cause distress and anxiety. A person will not derive pleasure from them and they are not voluntary.

Support for Family, Friends and Carers

It may be useful to inform loved ones and carers about OCD to help them to understand the condition. This may take the pressure off the person who has OCD to explain and defend their behaviours. It may also relieve tension between the person who has OCD and the people they live with (SANE 2018).

It can be difficult to live with someone who has OCD. Their behaviour may seem hard to understand, intense and/or disruptive. It’s important to keep in mind they are likely to be as distressed (if not more) by their symptoms as you are (SANE 2018).

There are plenty of OCD resources available to help clear up misunderstandings and concerns about OCD and its symptoms.

Listen to this OCD Stories podcast episode about living with OCD:

Additional Resources


Test Your Knowledge

Question 1 of 3

Which one of the following is considered to be a compulsion?


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