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Obsessive Compulsive Disorder

In our inaugural post, we are showcasing Obsessive Compulsive Disorder (OCD). Our South Island Psychiatrist Agata Moody (Shown left) has a special interest in OCD, and many of our other psychiatrists are highly experienced in the medical treatment of OCD. In this post, Dr Moody and Dr Caleb Armstrong, Clinical Director, shed some light on OCD detection and management.


What is OCD?

Everyone experiences intrusive thoughts – uninvited ideas, images, urges and sensations that may be weird and even horrible – but most people give them little attention and such thoughts are soon forgotten.

OCD is a disorder in which people have recurrent intrusive thoughts (obsessive thoughts) that cause emotional distress and respond with physical or mental actions to gain relief (compulsions). Although compulsive behaviours do alleviate mental distress in the short-term, they lead to additional thoughts of a similar nature in the longer term, maintaining and strengthening the obsessive-compulsive cycle.

OCD in History

Obsessive Compulsive Disorder can be recognised in historical figures. St Ignatius of Loyola wrote “After I have trodden a cross formed by two straws, or after I have thought, said, or done some other thing, there comes to me from ‘without’ a thought that I have sinned, and on the other hand it seems to me that I have not sinned; nevertheless I feel some uneasiness on the subject, inasmuch as I doubt and do not doubt. That is a real scruple and temptation which the enemy sets.”

German Psychiatrist Karl Westphal gave an excellent description of obsessions in 1877 - ‘thoughts which come to the foreground of consciousness in spite of and contrary to the will of the patient, and which he is unable to suppress although he recognises them as abnormal and not characteristic of himself’.

How Common is OCD?

Previously thought to be a rare disorder, results from large epidemiological studies show much higher lifetime prevalence of OCD ranging between 2.5 and 3%-, and a six-month prevalence of 1.6%.

The variety of OCD symptoms is astonishing, and they are often not visible to others. People with OCD often do not attribute their difficulties to OCD and are very surprised when they receive a diagnosis. Knowing more about the intricacies of emotional, behavioural and cognitive aspects of OCD can help them to self-identify the condition and enable them to reach out for help sooner.

OCD has often been misrepresented and stereotyped in films and TV series, and on social media. Accurate representations of OCD are becoming more common, from the film “Aviator” to the TV drama “Pure” and the documentary “Living with Me and My OCD”, and there are high-profile figures such as Charlize Theron, Justin Timberlake and NZ’s Benee who are open about their diagnosis.

‘Living with Me and my OCD’ is an interesting documentary about OCD which is available on Youtube here -

What are the most common symptoms?

OCD is usually first experienced as a child, adolescent or young adult and as a new parent during pregnancy or caring for a baby. OCD has a chronic course with occurrence of many comorbidities in a life span. Chances of remission of untreated or sub optimally treated OCD are reduced with age.

PADA – (Perinatal Anxiety and Depression Aotearoa) has information about perinatal OCD here:

The early onset of OCD is more common in boys, with up to 25% of men having had an onset of OCD before the age of 10. Some studies indicate similar prevalence in women and men whilst others show higher prevalence in women.

Obsessive-compulsive symptoms are often present in early childhood, such as compulsive touching of objects, counting, arranging items in a certain way, and performing tasks in odd or even numbers. These symptoms tend to be transient, mild, and they do not interfere with normal functioning. They might however indicate an increased risk of developing an obsessive-compulsive disorder requiring treatment in the future.

The obsessive thoughts often involve fears and doubts about contamination, harm to oneself or family members, or simply a sensation that something doesn’t feel right. They usually concern something that the person cares deeply about – health, safety, relationships, sexuality, gender identity, religion, morality, symmetry...

While some compulsions are overt – hand cleaning, switch checking, repetitive touching of objects, some behaviours are not recognised as compulsion by the person themselves or others, for instance avoidance, reassurance seeking, endless consultation of the internet, or mental acts such as rumination, silent repetition of a comforting mantra (“I am a good person”) or repeatedly reviewing past acts to check nothing problematic happened.

Popularly known as “Pure O” some people’s experience of OCD is primarily mental, which can make this truly a solitary battle in a person’s mind.

People with OCD often have additional diagnoses: forms of anxiety, coexisting mood disorders (depression, bipolar disorder), impulse control disorder; substance use disorder, eating disorders, ADHD, autism and others. Sometimes, the presence of another disorder can lead to OCD being overlooked, for instance where an Autistic Spectrum Disorder and OCD coexist.

OCD tends to occur before the onset of mood disorder. The dyad of bipolar affective disorder and OCD is a particularly disabling condition with a higher prevalence of alcohol use disorder and suicidality. Trauma can trigger the development or exacerbation of OCD.

Diagnostic and treatment delay

There is on average a 10-year delay between onset of first symptoms and seeking help. Even after asking for help, there is often a 6-year gap before receiving a diagnosis and a further 1-year or more before adequate treatment is established. The average time lag between onset of symptoms and adequate treatment is 17 years!

A third of the people diagnosed with OCD do not receive appropriate treatment at all. This treatment gap is not limited only to people with moderately severe OCD but also affects people with severe OCD.

A major factor contributing to these diagnostic and treatment delays is that the intrusive thoughts in OCD are egodystonic. The unwanted thoughts go against the person’s sense of who they want to be as a person, and are often associated with embarrassment, shame and guilt. These feelings can stop people with OCD from talking about their struggles or asking for help. It is particularly difficult to disclose intrusive thoughts about taboo subjects such as physically or sexually harming others.

How can GPs and other health professionals detect OCD earlier?

We think that the use of broad questions helps with OCD detection. Using the following screening questions can be very helpful:

  • “Do you experience unwanted thoughts, images or impulses that repeatedly enter your mind, despite trying to get rid of them? For example, worries about dirt or germs, or thoughts of bad things happening.” (Screening for obsessions. Images is highlighted because sometimes the patient may experience unwanted images or ‘visions’ which can easily be confused with psychotic symptoms.

  • “Do you ever feel driven to repeat certain acts over and over? For example, repeatedly washing your hands, cleaning, checking doors or work over and over, rearranging things to get it just right, or having to repeat thoughts in your mind to feel better.” (Screening for compulsions – an alternative question is “Are there any rituals you do to prevent bad things from happening?”)

  • “Does this waste significant time or cause problems in your life? For example, interfering with school, work or seeing friends.”

A positive response to question 1 or 2, with distress or dysfunction as a result, warrants consideration of treatment or referral.

When conditions associated with OCD are present, actively consider the possibility of co-existing OCD. For example, co-existing panic disorder, depression, suicidal thoughts will often prompt people to seek help. Repeated consultation of a health professional may be a compulsive behaviour in people experiencing intrusive thoughts about health.


The severity of symptoms, duration of illness, presence of other comorbid conditions and the level of functional impairment are taken into consideration during treatment planning.

The guidance of the British National Institute for Health and Care Excellence (NICE) recommends a low intensity psychological therapy (up to 10 hours) as the first step for treatment of OCD with a mild level of functional impairment and distress. Cognitive Behavioural Therapy and Exposure Response Prevention are evidence based and well-established therapeutic interventions. This is not ‘talk therapy’ but a therapy based on supporting people with OCD to engage in strategies to combat the cycle of OCD by identifying a hierarchy of feared situations. Then the person is encouraged to address some of the less anxiety provoking items on that list without engaging in compulsions afterwards. With the support of the therapist they can then address the more difficult items. Doing this therapy can greatly reduce symptoms and improve quality of life for people with OCD.

In a moderate severity of illness, higher intensity therapy is recommended or ERP combined with SSRI antidepressants (sertraline, fluoxetine). Medications can reduce the intensity of obsessive thoughts, making it easier for people with moderate to severe OCD to engage and persist with therapy.

The response to treatment can take longer than a month and higher doses of these antidepressants are often needed in case of poor or partial response. If response to treatment is suboptimal after 3 months, a combination of medications and psychological therapy is recommended. Many GPs will not be confident to prescribe very high doses of these medications, and a psychiatrist should be involved at this point.

Other medications such as low doses of antipsychotics can be added along with treatment with SSRIs to increase the efficacy of treatment where response to monotherapy is limited.

Clomipramine, tricyclic antidepressant is also used in treatment of OCD in absence of response to SSRIs antidepressants.

About 70% of people respond to treatment and 30% of people suffers from chronic symptoms, which are resistant to treatment. Sometimes, adding in another medication such as riluzole, galantamine, aripiprazole or amisulpiride may help.

Discontinuation of treatment with medications leads to a two-fold increase in the risk of relapse compared to people who remain on medications. However, completing a course of ERP can improve the chances of a person with OCD discontinuing medications successfully.

There are emerging treatment strategies for OCD such as Transcranial Magnetic Stimulation or deep brain stimulation but those treatments are not well-established and are not easily accessible.

Early detection and diagnosis are key factors contributing to successful treatment.

Could I have OCD?

The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) is often used by clinicians to measure OCD symptoms. If the items in the Y-BOCS seem like they apply to you, this could indicate the presence of OCD.

There are numerous online questionnaires about OCD, however we do not have the ability to review them all and comment on their validity. Perhaps it is better to ask yourself –

  1. Do I have repetitive thoughts, images, or visions of an unpleasant and unwanted nature?

  2. Do I try to reduce the distress I feel due to this by engaging in repetitive acts or rituals?

  3. And is this distressing and interfering with my life?

If the answer to 1 or 2 is yes, you may well have OCD and should seek help from your GP, psychologist, counsellor or Psychiatrist. Another great source of information is the website associated with the NZ support group Fixate ( OCD is treatable!


OCD is one of the most prevalent mental health disorders

  • OCD was ranked by The World Health Organization (WHO) as one of ten most disabling disorders of humans next to diabetes, hypertension or cancer;

  • OCD is under-diagnosed and under-treated. The average treatment gap is ~17-years.

  • OCD is a heterogenous condition, and usually has a chronic course

  • The first lines of treatment are Exposure Response Prevention therapy and/or SSRI medication

  • The majority of individuals respond well to treatment. Prognosis is poorer in earlier onset OCD, male gender, co-existing tic related disorders, long duration of untreated or sub-optimally treated illness.

  • Actively consider the possibility of OCD, especially when co-morbid conditions are present.

  • People with OCD often do not attribute their difficulties to OCD and are very surprised when they receive a diagnosis.

Treatment Guidelines


Do you have concerns that you or a relative may have OCD?

We are here to help and many of our psychiatrists have a special interest in OCD.

Your GP, psychologist or GP practice nurse can refer you to our clinic, or another clinic of your choice.

Here are some online tests with reasonable validity that may help you decide – a short version of the Yale-Brown Obsessive Compulsive Scale Yale Brown Obsessive Compulsive Scale (Y-BOCS) Calculator ( and the OCI-R OCD Test | Obsessive-Compulsive Inventory Revised (OCI-R) (


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