You’ve probably heard it before; “I’m so OCD”, a flippantly shorthand expression for being a neat freak or a creature of habit. But for people who live with obsessive-compulsive disorder, the term used is not so amusing. OCD is a disorder that can be serious and debilitating. And more than half a million Australians suffer from it.

Most people’s understanding of OCD is based on pop-culture figures such as Sheldon Cooper from the TV series The Big Bang Theory, who is obsessed with hygiene and follows a strict routine for most of his everyday life, or Adrian Monk in Monk, who fears germs, crowds and milk, and these characters are often depicted as quirky, unusual and antisocial.

But what is OCD in real life? What is it like to have the disorder? And how is it treated?

What is OCD?

OCD is characterised by obsessive thoughts and compulsive acts accompanied by severe anxiety, says David Berle, associate professor in clinical psychology at the University of Technology Sydney. The thoughts are intrusive – unwanted and repetitive. A person feels compelled to perform certain actions, mental or physical, to alleviate the obsessive thoughts. For example, a person may have doubts or concerns about germs or contamination, and will worry about getting sick from them (the obsession). To reduce the anxiety around that thought and self-soothe, the person might wash their hands over and over again (the compulsion).

“Almost all of us will have intrusive, unwanted thoughts at times ... but for people that actually have OCD, it is associated with a very significant degree of impairment,” Berle says.

The most common examples of OCD are the ones that people can see physically – the obsessive handwashing, checking appliances are off, flicking light switches, says Richard O’Kearney, emeritus professor in clinical psychology at the Australian National University. But many people with OCD live with internalised obsessions, too.

Someone might have thoughts about harming their children, for example, says O’Kearney, even though they know they never would – but the thought gets caught on a loop and that person might start performing ritualistic actions to ease those thoughts. “Compulsions are those actions that the person does in order to do something about the obsessions they experience. So, it might be overt actions like avoiding the children, or checking on them,” says O’Kearney.

But it can also manifest in other ways, such as someone thinking that unless they do their checking rituals something bad might happen. This can escalate to seem like a matter of life and death. For example, a person might feel compelled to flick a light switch five times, says Berle. “They can have a fear that if they don’t perform the compulsion, a person they love might die.”

Obsessions can be soothed by mental rather than physical compulsions, says O’Kearney, “going over memory or doing ritual-type mental activities like counting”. An example of this, says Berle, is that “a person may feel that there are particular ‘good’ numbers or sequences of thoughts which reduce the likelihood of their obsessive doubt eventuating”.

How does OCD affect people who have it?

Kate, who is studying her masters in clinical psychology, developed signs of OCD in her early childhood. “From a young age I had tendencies,” she says. “When I was little, my mum would see me ordering things a certain way before I went to bed.

“I would tap things in a certain way, or close cupboards, and I was quite stressed if I couldn’t do these things.”

It wasn’t until Kate was in high school that she was diagnosed with mild to moderate OCD. By then, the disorder was having an effect on her day-to-day life. “From year 10 onwards, the form it presented most predominately in was checking – checking gas-stove knobs, checking doors – the fear that if I didn’t check, the house would go up in flames and everyone would die, and it would be my fault.

“I had high insight, so I was very aware that the chances of something happening were slim, and I logically and rationally knew that, but I just couldn’t help it.”

People experience OCD in a variety of ways, even if they present with similar symptoms. “While my symptoms were distressing, and they had an impact on my life, I was only diagnosed as being mild to moderate, which shows just how bad it can be for some people,” Kate says.

OCD can also present itself in the form of intrusive and shocking thoughts that go against a persons beliefs.

Because of the debilitating effect it can have, Berle says, it’s not uncommon for a person to develop other disorders such as depression or an anxiety disorder.

“It remains unclear precisely why that is. It could be that there is some shared psychological underpinning to both conditions ... it also can be that someone has OCD and then, understandably, they can experience depression because they are struggling to cope with their OCD.”

OCD can also present itself in the form of intrusive and shocking thoughts that go against a persons beliefs, says Berle. For example, “some people can experience very embarrassing sexually themed obsessions about inappropriate sexual acts, or obsessional thoughts that might go against their religious beliefs”.

All of this can be exhausting, debilitating and even tormenting for a person, and it can significantly disrupt their everyday life. OCD is often referred to as the “doubting disease” because it makes a person doubt themselves.

“The person can start to doubt their own character and start to wonder, if I have such horrible thoughts and impulses so often, does this mean I may actually want to act on them?” says Berle. This can make a person start to doubt their moral integrity, he says, even though the fact they are upset by these thoughts shows that they don’t necessarily want to act on them. Most people with OCD are aware that what they are thinking isn’t rational, he says, which contributes to it being so frustrating. (A small number “may not have insight that their obsessions are irrational”.)

Is the portrayal of OCD in pop culture accurate?

Movies and TV shows are full of characters with quirks or eccentricities that are designed to endear us to them. Most of the time, it isn’t overtly said that these characters have disorders such as OCD or anxiety or are somewhere on the autism spectrum, but their habits and idiosyncrasies often align with some of these diagnoses.

However, Berle says that rather than these characters being accurate and empowering representations of OCD on screen, they are often the butt of a joke. “In popular culture, they don’t often show the distress and interference in family ... they usually tend to highlight the kind of quirkiness of things and the interesting and curious features of OCD without acknowledging it can be distressing.”

These characters also often have signs of obsessive compulsive personality disorder (OCPD), which is harder to diagnose. “OCPD is thought to be a more enduring personality disturbance which isn’t necessarily defined with obsessions and compulsions. It is more to do with a rigid, perfectionist personality style which manifests with people being very inflexible,” he says.

For example, Sheldon from The Big Bang Theory is afraid of germs and performs day-to-day tasks almost ritualistically, but he also is a perfectionist who is extraordinarily unmoving when it comes to changing plans or doing something he doesn’t want to do. He is also presented as being socially awkward and a quirky genius. Yet while he is portrayed as being frustrating to everyone around him, these same features are what audiences are meant to find endearing.

Berle says those kinds of representation “really undermine the experience” of having OCD because “there is almost this sense that being a little OCD is a good thing. But, in actual fact, OCD as a disorder is extremely distressing for a person and really interfering in their everyday life.”

What causes OCD? And how is it diagnosed?

“There is a tendency for OCD to run in families, but it doesn’t explain every instance,” says Berle.

Like many things to do with the brain, there are still many unknowns when it comes to the causes of OCD and, as with most mental illnesses, it’s an interconnection between biology, psychology and socio-environmental factors. “Children might pick up indicators from their parents, even if there isn’t a strong inherited tendency at play,” says Berle. For example, a child might pick up the habit of constantly washing their hands because they are mimicking what their parents do.

Given she showed symptoms at such an early age, Kate says hereditary and biological factors were the likely origin of her OCD. “I had symptoms practically from when I could walk, and I have a presence of it in my family.”

Once people develop symptoms that they identify aren’t normal, they don’t always seek help straight away, says O’Kearney. “People with OCD often wait a long time before they seek help. That’s primarily because they manage the OCD and work around it.”

To be diagnosed as having OCD, a person’s obsessions and compulsions need to start having an impact on their life. There is no single test but there are criteria for health professionals to follow to diagnose people, based on a person’s behaviours, thoughts and feelings.

Once someone has been diagnosed, treatment is available, says O’Kearney, but making a full recovery is unlikely. “It’s a chronic illness that is stress sensitive, so even when people get the best treatment, and they have the best response to treatment, they will be at risk that the OCD will come back during stressful times.”

How is it treatable?

People can battle with themselves for years before they seek help, if they do at all. Some wait because of shame and guilt about their OCD, says O’Kearney. Others are embarrassed and worried they’ll be judged, especially if their thoughts are, say, sexual in nature.

The two main lines of treatment are psychological therapy, which is typically exposure and response prevention (ERP), and medication-based treatment.

‘I would fall asleep, and when I would wake up everything was OK. I was surprised by how quickly it worked.’

ERP gradually builds up a person’s tolerance to things that trigger their obsessions without engaging in the compulsive response, says Berle. A person who has issues with germs might be asked to touch something they perceive as dirty and refrain from washing their hands afterwards.

Kate worked through her OCD with her psychologist through a combination of ERP and medication. “Mostly it was just working with my psychologist to resist checking at night. She told me my anxiety would go up, and I would have catastrophic thoughts, but over time it would go down,” says Kate.

“I would fall asleep, and when I would wake up everything was OK. I was surprised by how quickly it worked.”

Medications such as selective serotonin reuptake inhibitors (SSRIs) are thought to influence the neurotransmitters in the brain so that OCD symptoms are suppressed. “People can get a lot of benefits if they work at it and get the right treatments,” O’Kearney says. “A lot of other treatments that are being developed are showing promise – other psychological treatments but also different types of brain stimulation that are working for depression, and they have shown to be helpful for OCD as well.”

Kate says her OCD still affects her, even 10 years after her diagnosis – but nowhere near as badly as when she was a teenager. And, despite the anxiety and stress it caused her when she was younger, she says it’s important to talk about and normalise OCD so that people don’t feel shame about their diagnosis.

“My experience with OCD definitely influenced my decision to go into psychology,” she says. “It’s not the reason I entered psychology, but it definitely played a part.”