What Is OCD?
Obsessive-compulsive disorder (OCD) is a treatable mental health condition where people experience intrusive, unwanted thoughts (obsessions) and feel driven to do repetitive behaviours or mental rituals (compulsions) to reduce anxiety or prevent harm.
OCD often becomes a loop: obsession > anxiety > compulsion > short-term relief, which trains the brain to keep repeating the cycle.
OCD has two key features;
- obsessions – these are unwanted thoughts, impulses, images and urges, such as ‘what if I have done something bad’ or ‘what if I shout out something obscene in church,’ and they make you feel repulsed, anxious or deeply distressed.
- compulsions – these are rituals, or repetitive things you do to try to ease the anxiety caused by the obsessions or to stop ‘something bad from happening.’ Their purpose is to ‘neutralise’ the obsession. Your compulsion might be repeatedly checking things, seeking reassurance or excessively washing.
The compulsions only help short-term, and eventually the obsession comes back, and you try the compulsion again, as it helped a little the last time, but with OCD, the brain gets “stuck” in this cycle:
obsession > anxiety > compulsion > temporary relief,
which then reinforces the obsession.
Table of contents
I am going to give an anonymised example from my clinical practice to illustrate this point. A person always asked their husband to call them when they get to work, or reach any destination.
- Trigger: Husband doesn’t call by the expected time.
- Intrusive thought / obsession: “Something terrible has happened (car crash, hospital, dead).”
- Anxiety/uncertainty spike: Distress feels urgent and intolerable.
- Compulsion / safety behaviour: Repeated calling/texting, maybe tracking, asking others, replaying routes in their head, etc.
- Short-term relief: “I feel a bit better” (or at least less panicky).
- Reinforcement: Brain learns “When I feel this fear, contacting/checking is what keeps people safe,” so next time the urge is stronger and the time-window gets tighter.
That last point is the key: the behaviour doesn’t just reduce anxiety — it teaches the brain the obsession was important, so the cycle keeps going.
It’s not that my client truly believed something terrible happened to her husband every day — it’s that she couldn’t tolerate the not knowing. The checking was an attempt to get certainty right now.” I’ve been working with OCD for two decades and this needing to know for sure; the need for certainty is a hallmark of obsessive compulsive disorder.
Over time this obsession > anxiety > compulsion > temporary relief, becomes a self-perpetuating loop; the OCD cycle, that is very hard to break without help. People with OCD usually have insight – like my client knew her obsessive thoughts were excessive, but she could not stop the compulsions – the most common thing I heard from clients, was some version of ‘it’s better safe than sorry.’ For many people the fear of what could happen if they stopped their rituals was intense. Psycho-education and breaking this cycle is the goal of effective OCD treatment.
OCD Symptoms
Obsessive-Compulsive Disorder manifests through a variety of symptoms, but they all revolve around the core cycle of obsessions and compulsions.
Common OCD Obsessions
OCD obsessions can be about virtually any topic, but some frequent themes include:
- Contamination: Fear of germs, dirt, viruses, or environmental contaminants (chemicals, etc.). A person might obsess that they’ll be infected or will infect someone else by touch. They might think “What if I touched something dirty and now my hands are deadly?”
- Harm: Fear of causing or failing to prevent harm to others or oneself. Examples: “What if I accidentally hit someone with my car and didn’t notice?” or a thought of stabbing a loved one pops up, causing panic that “I might lose control and do it.”
- Violent or Sexual Intrusive Thoughts: Unwanted mental images or impulses of violent acts, inappropriate sexual acts, or other taboo behaviors. The person finds these thoughts repulsive, which is why they’re so distressed by them.
- Scrupulosity: Obsessions about morality, religion, or being a “bad” person. For instance, “I think I blasphemed internally – I might be sinning,” or “What if I secretly am a pedophile because I had a weird thought when seeing a child?” These thoughts violate the person’s values, hence the anguish.
- Symmetry/Order: A need for things to be “just right,” perfectly even, or symmetrical. The obsession isn’t necessarily that something bad will happen, but a feeling of extreme discomfort or wrongness until things are aligned or done in a certain way.
- Health: Obsessive fears of having a serious illness (despite medical reassurance), also known as health anxiety or hypochondriacal OCD. Every headache might mean “brain tumor” in their mind, for example.
- Relationship doubts: (Sometimes called R-OCD) Obsessions about whether one really loves their partner, whether the relationship is the “right one,” or fixating on perceived flaws of the relationship or partner endlessly.
- Superstitious or Magical Thinking: Belief that certain numbers, colors, or actions are lucky or unlucky, and if “rules” aren’t followed, disaster will strike. E.g., “If I don’t tap the door frame exactly 4 times, my parents will have an accident.”
It’s important to emphasize that the person with OCD does not want these thoughts – they are ego-dystonic, meaning the thoughts go against the person’s own beliefs or desires. A gentle person might get violent intrusive thoughts precisely because they would never want to hurt anyone; a devout person gets blasphemous thoughts that horrify them; a caring parent gets an image of harming their baby and is sick with guilt over it.
Common Compulsions
To neutralize the anxiety or “undo” the obsessions, people with OCD engage in compulsions. Compulsions can be behavioral (actions) or mental (invisible thinking rituals). Some common compulsions:
- Excessive washing/cleaning: Washing hands repeatedly, showering for hours, cleaning household surfaces over and over, doing laundry excessively, avoiding physical contact like handshakes – all aimed at removing contamination.
- Checking: Checking locks, stoves, appliances, car brakes, etc., multiple times before feeling satisfied. Returning to a location to check one didn’t cause an accident. Checking one’s body for signs of illness repeatedly.
- Repeating actions: This can be tied to symmetry or magical numbers – e.g., turning a light switch on and off exactly 7 times because 7 is “safe,” or re-reading a paragraph until it feels perfect.
- Ordering/Arranging: Aligning items precisely, arranging books or clothes until it “feels right.” Rearranging things until symmetry is achieved.
- Hoarding: Difficulty discarding items, even trivial ones, due to fear something bad might happen if they throw it away, or that they may need it later. (Note: Hoarding can also be its own disorder, but some OCD individuals hoard as a compulsion driven by specific fears.)
- Mental compulsions: These include mentally repeating certain words or prayers, reviewing events in one’s mind over and over to “check” something, or trying to replace a “bad” thought with a “good” thought. For example, after an intrusive blasphemous thought, a person might silently recite a prayer 10 times perfectly to feel “forgiven.” Or if a “bad” thought about harm occurs, they might force themselves to visualize a counteracting image (like healing the person) to cancel it out.
- Reassurance-seeking: Constantly asking others for reassurance. “Are you sure I didn’t offend you? Are you sure this mole doesn’t look like cancer? Promise me everything is okay?” This is a compulsion because it’s done to relieve anxiety, though the relief is short-lived.
- Avoidance: Avoiding triggers of obsessions. While not an active “ritual,” avoidance is often considered a compulsion because it’s done to prevent anxiety. Examples: someone with driving-related OCD might stop driving entirely to avoid the spike of “maybe I hit someone.” Or a person with intrusive thoughts about violence might avoid being around sharp objects or avoid being alone with certain people. Avoidance temporarily prevents anxiety, but it actually reinforces the fear in the long run.
What OCD Feels Like
People with OCD often describe feeling trapped in their own mind. They know the behaviours or thoughts are irrational, yet the fear feels so real. There is often significant shame – they might think “What kind of person am I to have these thoughts?” or they fear others will think they’re “crazy” if they knew. As a result, many sufferers hide their symptoms for years. It’s not uncommon for someone to silently struggle, perhaps functioning adequately on the surface while internally battling intrusive thoughts all day.
OCD can be likened to an “internal bully” or a broken alarm that keeps saying something’s wrong when it isn’t. It can also be physically and mentally exhausting – imagine feeling like you must perform rituals for hours or you’re wracked with anxiety; it wears a person out. Many with OCD also experience secondary depression (feeling hopeless or down because they’re dealing with this chronic stress).
How Common is OCD and Who Gets It?
“OCD affects roughly 1–2 people in every 100.” University of Galway
“Lifetime prevalence is often cited around ~2–3% (e.g., 2.5% in some clinical overviews).
OCD is a lot more common than people realize. Internationally, about 1-2% of people will experience OCD at some point – that’s 1 or 2 in every 100. In Ireland, some estimates suggest the prevalence might be slightly higher (possibly up to 2-3%). That translates to tens of thousands of individuals in Ireland living with OCD. It affects all genders and backgrounds roughly equally. Typically, OCD symptoms first appear in late childhood, the teen years, or early adulthood. There are cases of very young children (even age 6 or 7) showing OCD-like behaviours, and there’s also a subset of cases that start in later adulthood, but those are less common.
Notably, OCD often goes undiagnosed for a long time. Many people don’t know their symptoms have a name. They might think they’re just “anxious” or even worry that they’re “crazy” or dangerous because of their thoughts. It’s often a relief when they learn, “This is OCD and it’s a known, treatable condition.”
OCD vs. Normal Fears or Habits
It’s natural to sometimes double-check things or want cleanliness. What differentiates OCD from normal caution or personality traits is degree and function:
- Distress: In OCD, the obsessions and compulsions cause significant distress. If a person cannot do their ritual, they may panic or feel extremely uncomfortable. A non-OCD person might prefer things clean, but if they’re a bit dirty one day, they’re not engulfed in anxiety.
- Time-consuming: OCD rituals can consume over an hour a day (often many hours). They interfere with daily routines. Normal habits are much less intrusive.
- Functional impairment: OCD can impair work (e.g., someone spending so long on rituals they’re late or miss deadlines), school (rewriting homework for perfection, thus not finishing on time), relationships (not wanting friends over because of contamination fears, etc.). Non-pathological traits don’t typically disrupt life to this extent.
- Feel out of control: People with OCD usually feel compelled against their will. They might describe it as “I feel I have to do this, even though I know it’s odd.” With a regular habit or preference, you’re in control – you might like a tidy desk, but it’s not like you’ll have a panic attack if it’s messy once.
- Relief vs. enjoyment: OCD compulsions don’t produce genuine satisfaction or pleasure – only fleeting relief or reduction of anxiety. In contrast, someone who likes cleaning might actually enjoy the result or feel satisfaction from the act.
Why Can’t People with OCD “Just Stop”?
From the outside, compulsions can look voluntary – after all, it’s the person’s own hand turning the lock repeatedly. But it’s important to understand that in the moment, the anxiety or sense of dread is so overwhelming that performing the ritual feels like the only way to survive or feel okay. The OCD brain is essentially tricking them: “If you don’t do this, something terrible will happen and it’ll be your fault.” Resisting that is extremely hard without proper training (like therapy techniques) – it’s like resisting the urge to run when you see a tiger. The fear is out of proportion, but it feels utterly real.
Additionally, performing the compulsion does work – briefly. It reinforces a learning: “Good thing I checked, otherwise disaster!” So the next time, the urge is even stronger. This reinforcement pattern makes OCD very sticky. It’s not a matter of willpower or intelligence – people with OCD often logically know nothing bad will happen, but the emotional brain doesn’t care about logic in that anxious moment.
What causes OCD?
OCD doesn’t have one single cause.
Most experts think it develops from a mix of biology (brain + genes), psychology (how someone relates to thoughts and uncertainty), and life experiences (stress, illness, big changes). This is sometimes called a bio–psycho–social model.
Genes and family history
- OCD can run in families, but it’s not guaranteed.
- If a parent or sibling has OCD, your risk is higher than average.
- Twin studies suggest genes may account for around 40–50% of vulnerability.
- There isn’t one “OCD gene.” It’s more likely many genes, each adding a small effect.
- Some people with OCD have no family history at all, so genes are only part of the picture.
Brain and body factors
Research suggests OCD involves differences in certain brain circuits linked to:
- detecting errors
- warning signals (“something is wrong”)
- checking and repeating behaviours
It can feel like the brain’s alarm system is stuck on.
- Serotonin and other brain chemicals seem to be involved, which is one reason SSRIs can help some people.
- Brain activity in these circuits can change with effective treatment, which supports the idea that OCD is a brain-based disorder, not “just habits.”
Thinking patterns that can feed OCD
Many people with OCD have common patterns such as:
- needing certainty and finding uncertainty unbearable
- feeling overly responsible (“If I don’t prevent it, it’s my fault”)
- overestimating danger (“If I don’t check, something terrible will happen”)
- treating thoughts as dangerous or meaningful (e.g., “If I think it, it might happen”)This is sometimes called thought–action fusion.
Treatment – Professional Approaches
HSE states OCD can be treated and describes CBT and ERP (gradual exposure without doing compulsions) as key psychological therapy, and notes SSRIs may also be used.
OCD is very treatable. The recommended, evidence-based treatments for OCD are a combination of specific psychotherapy and, in many cases, medication. In Ireland (as in most countries), the consensus first-line treatment for OCD is Cognitive Behavioural Therapy (CBT) with a technique called Exposure and Response Prevention (ERP). For moderate to severe OCD, often an SSRI medication is recommended as well.
Please see my Guide for a complete overview of OCD treatments and therapy options.
FAQs
Below are answers to some frequently asked questions about OCD, especially common queries from people in Ireland:
Q: Is OCD curable, or will I have it for life?
A: OCD is often a chronic condition in the sense that one might have a predisposition to it lifelong. However, with the right treatment, it is absolutely possible to live free from significant OCD symptoms. Many people experience dramatic improvement or even full remission of symptoms through therapy (ERP) and/or medication.
Q: What’s the difference between OCD and just being a perfectionist or very tidy?
A:The term “OCD” is often misused in casual conversation (e.g. “I’m so OCD about my desk, it has to be perfect”). In reality, clinical OCD is far more than liking things neat. The key differences lie in distress, dysfunction, and the presence of true obsessions/compulsions. A person who is simply orderly or a perfectionist in personality might indeed like things clean or done a certain way, but they typically enjoy or take pride in that orderliness, and it doesn’t cause them intense anxiety if something is off – it might annoy them, but not panic them. In OCD, the person usually dislikes their need for order or their compulsions; they perform them out of anxiety and dread, not because it brings satisfaction.
Q: I have intrusive thoughts of harming my loved ones. Does that mean I’m dangerous or deep down want to do it?
A: No – in fact, the very opposite is usually true. Intrusive harm thoughts are a classic OCD symptom, and people who experience them are typically very gentle, caring individuals who would be horrified to actually hurt anyone. The content of OCD obsessions almost always contradicts the sufferer’s true values.
Q: How long does it take for ERP therapy to work?
A: It can vary from person to person, but many people start noticing improvements within a few weeks of consistent ERP practice. IOCDF notes a typical ERP course is often 12–20 sessions, adjusted to individual needs.
Q: Can I recover from OCD without medication?
A: Yes, absolutely. In fact, therapy (ERP) on its own is the first-line treatment for most cases of OCD, especially mild to moderate severity.
Q: How do I find an OCD therapist in Ireland?
A: Finding a therapist with the right expertise is crucial for OCD. Ask your GP for referrals and make sure the person is qualified and experienced in ERP.
Q: Does OCD ever go away on its own?
A: It’s uncommon for severe OCD to simply vanish without any intervention. Mild symptoms might ebb and flow, and sometimes life circumstances can lead to a temporary decrease (for instance, a person might have less OCD when very busy with something else). But generally, OCD is a self-reinforcing cycle – without consciously addressing it, it tends to persist or even worsen over time. Many people who don’t seek proper treatment end up having chronic OCD for years.
Q: I’m embarrassed to talk about my OCD symptoms – how do I start that conversation with a doctor or therapist?
A: It’s completely understandable to feel embarrassed – OCD often latches onto themes that feel private, shameful, or just silly when spoken aloud. Remember that health professionals are bound by confidentiality and have literally heard everything. Truly, you likely won’t shock them.
Getting help in Ireland
Talk to your GP (can refer to a trained therapist).
HSE guidance on symptoms/treatment (good authoritative external link).
OCD Ireland for support groups and information.
