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For adults and parents
Exposure and Response Prevention (ERP)
ERP has the strongest evidence base for OCD, and it is routinely delivered badly or not at all. This page sets out what it is, what happens in a session, and what makes it fail.
What ERP is
Exposure and Response Prevention is a specific behavioural treatment. You deliberately approach the thoughts, situations and sensations that set off your anxiety, and you deliberately do not do what you normally do to make the feeling stop. Exposure alone is a bad day; response prevention alone is white-knuckling.
The logic is simple. The compulsion works: washing, checking, asking, reviewing and avoiding each bring relief within seconds, and that relief teaches your brain that the danger was real and the ritual prevented it. The thought then returns louder, the ritual gets longer, and the ground it governs expands.
Why it is not the same as general CBT, or as talking therapy
CBT is a family of treatments and ERP is the member with the best evidence for OCD. The standard cognitive move, examining the evidence for a thought, is actively unhelpful here. People with OCD are already expert at reasoning about their fear, and doing it again in session is a fresh, professionally delivered dose of reassurance.
Ordinary talking therapy has the same problem. Exploring where the fear came from does not change what you do at 11pm when the doubt arrives: OCD is maintained in behaviour and treated there.
If you have had “CBT for OCD” before and it did not work
Ask what actually happened in the room. If you talked about the thoughts, rated their likelihood and left with a thought record, you had general CBT delivered to a problem that does not respond to it. That is not your failure.
Properly delivered ERP feels different by the third session: doing rather than discussing, with much of it outside the session.
The hierarchy, and how it is built
A hierarchy is a list of what you avoid or ritualise around, ordered from manageable to genuinely hard, with a rating out of 100 for difficulty. It stays a working document. Here is a composite contamination example, from an adult who fears passing illness to their family:
- Touch the inside handle of my own front door, no washing for thirty minutes (25)
- Touch a supermarket trolley handle, then eat a sandwich without washing first (40)
- Sit on a bus seat in work clothes, then sit on my own sofa in those clothes (55)
- Use a public toilet, wash once for twenty seconds only, no second wash (70)
- Do all of the above and then make my daughter’s packed lunch (90)
The last item is not a stunt. It is the actual feared outcome, being the person who makes their child ill, and it is why the other items exist. A hierarchy that never reaches the real fear will not resolve the problem.
What happens in a session
- We review the week: what you practised, what you avoided, what the OCD did in response.
- We agree the exposure for today, from the hierarchy, out loud, before anything happens.
- We agree the response prevention explicitly: what you will not do, including the mental rituals.
- We name what you expect to happen: the specific prediction, not a vague sense of dread.
- You do it. I am there, and with children I usually do it first or alongside them.
- We stay with it long enough for something to be learned, and we repeat it, varying the context.
- We check what actually happened against the prediction you made, in your own words.
- We set the homework, in writing, before the session ends.
Nothing is sprung on anyone. I do not produce unexpected objects or spring scenarios for effect. Surprise teaches the one lesson we cannot afford: that therapy is where unpredictable bad things happen.
Response prevention is the half that does the work
Most people can manage the exposure. The difficulty is what they do afterwards, and often during it. Response prevention means dropping the compulsion in every form: washing, checking, reassurance sought from a partner or parent, Googling, mental reviewing, the internal check for whether the anxiety has gone.
Covert compulsions are invisible and can run continuously: rehearsing what you did, replaying a conversation to confirm you said nothing terrible, saying a phrase in your head, reassuring yourself that you would never do that. If they carry on during an exposure, the exposure is neutralised. Spotting them is a large part of my job.
Why we are not waiting for the anxiety to come down
Older ERP taught people to stay until anxiety halved. That is not the mechanism. On the current understanding, from inhibitory learning, what matters is expectancy violation: you predicted something specific, it did not happen, and you noticed.
So we vary the context: different places, different times, no safety behaviours, sometimes while anxiety is still high. An exposure can succeed even if you felt awful.
Homework between sessions
An hour a week does not treat OCD. What does is what you do on the other six days. Homework is agreed in session, written down and specific: which exposure, how often, for how long, and what you predict.
Homework not happening for two weeks running is clinical information rather than a telling-off. It usually means the step was pitched wrong, or something at home is being accommodated.
Children and adults
The mechanism is identical; the delivery is not. With a younger child, ERP is externalised and gamified: the OCD gets a name and becomes a bully to beat. Parents are trained directly, because reducing family accommodation is one of the strongest levers in child OCD. With a teenager it looks closer to adult treatment: the young person holds the plan and parents step back.
Where a young person will not attend, ERP can be delivered through the parents alone. That is what SPACE is for.
What makes ERP go wrong
- Covert compulsions never identified, so every exposure is quietly cancelled out.
- Reassurance from family, answering the question the treatment needs left unanswered.
- Exposures done as endurance tests, gritted through and never repeated.
- A hierarchy that never progresses, because the top of the ladder is never approached.
- Safety behaviours smuggled in: sanitiser in a pocket, a phone within reach, a particular person present.
- Weekly sessions with no practice in between, producing a pleasant hour and no change.
How long a course runs, and working with me
Most straightforward adult courses run to around 12 to 20 sessions after the 90-minute assessment; children are often 12 to 16. Weekly at first, then spaced out, so you finish as your own therapist. NICE recommends CBT including ERP as a first-line treatment for OCD, and it is also the core of treatment for phobias.
I am board certified in Behavioral and Cognitive Psychology by the American Board of Professional Psychology, HCPC-registered and chartered with the BPS. I am a psychologist and do not prescribe; I work alongside GPs and psychiatrists where medication is considered. I see people online across the UK and in person near Ravenshead, Nottingham and Mansfield.
Common questions
Will you make me do something I have not agreed to?
No. Every exposure is chosen and agreed by you, in advance, before it happens. I never use surprise as a technique, because surprise teaches you that therapy is unsafe, which is the opposite of what we need. You decide what the next step is and when you take it. My job is to make sure the step is genuinely useful, that you are not quietly neutralising it, and that we do not spend six weeks on something you already found easy.
Does ERP work if all my compulsions are mental?
Yes, but the mental rituals have to be identified first. Reviewing a memory, silently arguing with a thought, checking internally for a feeling of certainty, praying in a set way, mentally reassuring yourself: these are compulsions, and they are done hundreds of times a day without anyone noticing. If they carry on during exposure, the exposure will not work and it will look as though ERP has failed. Mapping covert compulsions is often the most useful part of the assessment.
How long does a course of ERP usually take?
For a reasonably straightforward presentation, expect somewhere in the region of 12 to 20 sessions after the initial assessment for adults, and often 12 to 16 for children. Sessions are weekly at first, then deliberately spaced out as you take over the work yourself. A long history, heavy avoidance, family accommodation or a co-occurring difficulty can extend that. After the assessment I will give you an honest estimate, and we will review progress rather than drift on.
Can ERP be done properly online?
Very often it is better online. Most of what OCD demands happens in your own kitchen, bathroom, bedroom and phone rather than in a consulting room, and video lets us work in exactly those places. I have watched people do exposures at their own front door, in their own bathroom, with their own school bag. Working at home also means parents can be brought in and out of a child’s session as needed. Some presentations do benefit from in-person work, and I will say so.
My child gets extremely distressed. Is exposure not cruel?
Done properly it is neither cruel nor a test of endurance. Steps are small enough to be achievable, chosen by the child wherever possible, and practised until they are boring rather than pushed until they are unbearable. What is actually cruel is leaving a child inside an illness that takes hours from every day and shrinks their world year on year. Most parents find treatment markedly less distressing than the rituals and meltdowns they were already living with.
I have had CBT before and it did not help. Would this be different?
Frequently, yes. General CBT for OCD tends to fail: weighing the evidence for a thought, rating how likely the feared outcome is and talking it through until it feels better all turn into compulsions, and the OCD absorbs them. ERP is a different procedure with a different logic. It changes what you do when the thought arrives rather than trying to settle the argument. If your previous therapy was mostly discussion, you may not yet have had the treatment.
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