Obsessive-compulsive disorder: symptoms

People who have obsessive-compulsive disorder (OCD) experience intrusive or obsessive thoughts and compulsions, which can overpower the mind. Unlike ordinary habits or personal rituals, the person is unable to stop engaging in these thoughts and behaviours, and the associated anxiety is not relieved by simple reassurance. It is sometimes called the ‘doubting’ disease, as fears and thoughts can be so strong that they fill the mind with doubt.

Repeated obsessions and compulsions can be frightening, embarrassing, and even painful, and they interfere markedly with work and social life.


Obsessions are recurrent and persistent intrusive thoughts, ideas or images that cause distress. Common obsessions include fear of contamination or dirt, concern about things being orderly and symmetrical, and fear of harm to self or others. Obsessions sometimes involve a fear that the sufferer will do something out of character, including violent behaviour or inappropriate sexual behaviour, which makes it hard for people to talk about them. However, people with OCD never actually act on these obsessional thoughts.


Compulsions are repetitive behavioural and mental rituals. The rituals and behaviours are usually related to anxiety and the need to make things safe. For example, compulsive hand washing is usually associated with a fear of germs, while ritual checking behaviours before leaving home are generally driven by worries that the home would otherwise burn down or be broken into. Hoarding, another OCD symptom, is usually associated with the fear of throwing away something that will prove vitally important in the future. The person is usually aware that these behaviours are excessive or unreasonable.


Many people with OCD have symptoms that last for years, and they often develop further anxiety problems and depression. OCD is exhausting and causes much mental anguish for its sufferers. This can be especially difficult for children who fear they are ‘going crazy’ and develop elaborate ways to hide the disorder from parents, teachers and friends.

Untreated, OCD in adolescents can be particularly devastating because it coincides with a crucial period of social and emotional development. Schoolwork, home life and friendships can be seriously affected.

Causes and treatment

It is estimated that OCD affects 2–3 per cent of the population at any time, and many cases develop before the age of 18. Research suggests OCD may be related to an imbalance of brain chemicals, including serotonin. Having a family member with OCD increases your risk of developing the condition.

OCD can be treated with a combination of medication and cognitive behavioural therapy (a commonly used form of counselling for anxiety disorders).

Is it OCD?

Being a little 'obsessional' can be quite normal and even beneficial. It is not the same as OCD, which is characterised by the presence of obsessions and compulsions, not just neatness or careful planning.

Which types of behaviours indicate OCD?
 What's OCDWhat's not OCD
AdultA man who washes his hands 100 times a day, until they are red and rawA woman who unfailingly washes her hands before eating
A 14-year-old boy who is late for school every day because he can't get out of the shower until he has lathered and rinsed exactly 41 timesA 16-year-old girl who spends 30 minutes washing and styling her hair every day before school
AdultA university student who must tap on the doorframe of every classroom 14 times before enteringA musician who practises a difficult passage over and over again until it's perfect
A 7-year-old girl who can't stop skipping over cracks in the footpath until she has done it 89 times because she fears that something terrible will happen to her mother if she doesn'tA 5-year-old girl who laughs with her friends while skipping over cracks in the footpath, reciting, ‘Step on a crack; break your mother's back’
AdultA woman who locks and relocks her door before going to work every day — for half an hourA woman who double-checks that her apartment door and windows are locked each night before she goes to bed
A child who checks over and over that the light switch is in the off position, even though it is obvious that the light is offA child who double-checks that the light switch is off as she leaves a room, just like her parents have asked her to do
Last Reviewed: 19 December 2012

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1. Obsessive compulsive disorder (revised October 2008; amended February 2012). In: eTG complete. Melbourne: Therapeutic Guidelines Limited; 2013 Mar. http://online.tg.org.au/complete/ (accessed Jun 2013).
2. Obsessive compulsive disorder in childhood and adolescence (revised October 2008). In: eTG complete. Melbourne: Therapeutic Guidelines Limited; 2013 Mar. http://online.tg.org.au/complete/ (accessed Jun 2013).
3. SANE Australia. Obsessive compulsive disorder; 2010. http://www.sane.org/information/factsheets-podcasts/180-obsessive-compulsive-disorder (accessed Jun 2013).
4. Beyondblue. Obsessive compulsive disorder (OCD). http://www.beyondblue.org.au/the-facts/anxiety/types-of-anxiety/ocd (accessed Jun 2013).


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