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For adults and parents
OCD with co-occurring ADHD
OCD and ADHD together is common, frequently missed, and one of the main reasons ERP stalls. This page explains why the combination confuses everyone, and how the treatment has to be built differently to work.
Why this combination gets missed
On paper the two look like opposites. OCD is the condition of over-control: checking, repeating, needing certainty. ADHD is the condition of under-control: forgetting, rushing, losing the thread. Clinicians hold that contrast in their heads, and when they see one clearly they stop looking for the other. So the picture that gets written down is whichever one shouted loudest in the room.
They co-occur more often than that mental model allows. And when both are present, each one hides the other. The result is a person who has been in treatment before, sometimes repeatedly, and who has half-improved, plateaued, or been quietly labelled as unmotivated. In my experience that label is almost always wrong. The treatment was correct and the delivery was not built for the attention it had to work with.
What gets mistaken for what
A child rereading the same paragraph because it did not feel right looks like a child who has drifted off. An adult sitting at a desk running a mental review of a conversation from Tuesday looks like an adult who is distracted. Mental compulsions are invisible, and from the outside they are indistinguishable from inattention.
It runs in the other direction too. Losing keys, missing appointments and forgetting instructions get attributed to OCD-related preoccupation. Rigid routines and elaborate lists get read as compulsions when they are actually a reasonable person’s compensation for a memory that cannot be relied upon. Careful functional assessment — what was going through your mind, what happens if you do not do it, what feeling are you trying to switch off — is what separates them, not the behaviour itself.
Why ERP is harder to deliver, specifically
Exposure and Response Prevention is the treatment of choice for OCD and it works. But look at what it asks of a person, and it is a list of exactly the things ADHD makes difficult.
- Resisting a compulsion is a working memory task. You have to hold the plan in mind — I am not going to check, I am going to let this feeling be here — while a very loud signal argues the opposite. Working memory is precisely where ADHD applies pressure, and when the plan drops out of mind, the compulsion happens before there is any decision to make.
- The payoff is delayed. ERP asks you to accept discomfort now for relief that arrives days or weeks later. Compulsions pay out in seconds. ADHD steepens the discount on delayed rewards, so the deal ERP is offering is objectively worse for this brain than for anyone else’s.
- Impulsivity beats intention. The gap between urge and action is shorter. Response prevention depends on that gap.
- Between-session practice needs organising. Most of the work in ERP happens outside the room. That requires remembering, initiating and sequencing a task that is unpleasant — the definition of a task that gets deferred.
- Long exposures lose the room. The classic 45-minute exposure assumes sustained attention on one aversive thing. Attention wanders, and an exposure that is not attended to does very little.
- Self-report gets unreliable. Recording ratings and frequencies after the fact is a memory task, and the data that comes back is often thin or reconstructed.
How I change the treatment
None of the above means ERP does not work. It means it has to be engineered rather than prescribed. The principles are unchanged; almost everything about the delivery is different.
Shorter, more frequent, more repetition
Instead of one long exposure, several brief ones — five or ten minutes — done repeatedly across the week. Short exposures done often produce better learning than a long one done badly, and they are far easier to actually start.
Externalise everything
If a plan lives only in someone’s head it will not survive the week. So the plan lives on the phone, on the fridge, in a repeating alarm, on a card in a pocket. Practice gets attached to a fixed time and a fixed place rather than to an intention. I write the instruction down in the person’s own words, in the session, before they leave.
Bring the reward forward
Since the natural payoff is delayed, we manufacture an immediate one. For a child that is a points system, a chart, something earned the same day. For an adult it is more often a concrete tracked streak and an agreed reward for the week rather than a vague expectation that the improvement will be reward enough. This is not bribery; it is compensating for a reward system that discounts the future steeply.
Reduce the working memory load
Fewer targets at a time. One exposure hierarchy, not four. Scripts for the hard moment, so that resisting a compulsion becomes reading a line rather than generating a plan under pressure. Where there is a partner or a parent, they become an external prompt — deliberately, with agreed wording, and without becoming the person who nags.
Structure the session itself
Tight agendas, written summaries, a check that the between-session task is understood before the session ends, and a between-session contact where useful. I would rather spend five minutes making sure the homework is genuinely doable than discover next week that it was never started.
I do not assess or diagnose ADHD
To be explicit: I do not provide ADHD assessments, diagnoses or reports, and I am not an ADHD service. What I offer is OCD and anxiety treatment for people who also have ADHD, diagnosed or suspected, adapted so that it actually fits.
I work alongside whoever holds the ADHD care — a psychiatrist, a paediatrician, an NHS or private ADHD service, or a GP under shared care. With your consent I will share what I am seeing in therapy, since a therapist watching someone attempt structured practice every week often has useful information for a prescriber. I am a psychologist and I do not prescribe.
Treating one without recognising the other
This is where the real cost sits. If the ADHD is not recognised, ERP is delivered as standard, the between-session practice does not happen, progress stalls, and the conclusion drawn is that the person is not ready or not motivated. People internalise that, and it makes them slower to try again next time.
If the OCD is not recognised, ADHD treatment gets optimised and the person still cannot function, because a substantial part of the day is being consumed by compulsions that nobody has asked about. Mental compulsions in particular go unmentioned for years, and they will not appear on any attention questionnaire.
Either way the pattern is the same: a treatment that should have worked, applied to half the problem. That is why I ask about both at assessment as a matter of routine, whether the referral is for an adult or for a child or teenager.
Working with me
I am a clinical psychologist with a PhD from the University of Washington and a postdoctoral fellowship at the Evidence-Based Treatment Centers of Seattle, where I was Director of Training and Education and then Assistant Director of the Child Anxiety Center. I am board certified in Behavioral and Cognitive Psychology by the American Board of Professional Psychology, registered with the HCPC, and chartered with the British Psychological Society. I am a Clinical Instructor at the University of Washington.
I see adults, teenagers and children online across the UK and in person near Ravenshead, Nottingham and Mansfield, weekdays until 9pm. The first step is a free 30-minute call. Tell me what has been tried and where it stopped working, and I will tell you honestly whether I think a differently built course of ERP would get further. You can also read more about how I work.
Common questions
Do you diagnose ADHD?
No. I do not provide ADHD assessment or diagnosis, and I do not screen for it as a service. What I do is treat OCD and anxiety in people who also have ADHD, whether that ADHD is formally diagnosed, under assessment, or strongly suspected. Where a diagnostic assessment is needed I will say so and help you work out who to approach, and I am happy to work alongside whoever holds the ADHD care — a psychiatrist, a paediatrician, an ADHD clinic or a GP under a shared care agreement.
Which should be treated first, the OCD or the ADHD?
There is no single right order, and in practice they are usually addressed in parallel rather than in sequence. What I would say is that untreated, unrecognised ADHD makes ERP harder to deliver, because ERP depends on sustained attention, planning and between-session follow-through. If someone is already receiving ADHD treatment and it is working, that generally makes the OCD work more efficient. If it is not in place, we adapt the therapy rather than waiting. Delaying OCD treatment indefinitely while an ADHD pathway proceeds is rarely the right call.
Can stimulant medication make OCD worse?
I am a psychologist and I do not prescribe, so this is a question for the prescriber. What I can tell you is that it comes up frequently, that clinical opinion is genuinely mixed, and that individual responses vary a great deal. Some people report that stimulant treatment makes it easier to engage with ERP because they can hold a plan in mind and follow through. Others notice more anxiety or more rumination. The practical answer is to track it deliberately rather than argue about it in the abstract, and I will feed back what I observe in therapy to the prescriber.
How is ERP different when someone has ADHD?
The principles do not change; the delivery does. Exposures are shorter and more frequent rather than long and occasional. Practice is scaffolded externally, with alarms, checklists, timers and a specific time and place rather than a general intention. Rewards are brought forward, because the natural payoff of ERP — relief that arrives later — is exactly the kind of delayed reward that ADHD makes hard to work towards. Sessions are structured tightly and written down. In my experience these adaptations are the difference between therapy that stalls and therapy that moves.
My child’s school says he is inattentive. Could it be OCD?
It could be either and it is often both, which is why this gets missed so regularly. A child performing a mental compulsion — rereading a line until it feels right, counting, replaying whether they said something wrong — looks exactly like a child who has drifted off. The useful question is not whether he was concentrating but what was going through his mind at the time. Inattention from ADHD tends to be everywhere and unrelated to content; inattention from OCD clusters around specific triggers, and the child usually knows something was happening even if they will not say what.
Do you see adults as well as children for this?
Yes. This page is written for both because the combination presents at every age, and a large number of the adults I see were identified as having one condition in childhood and the other much later. Adults with OCD and ADHD often describe years of therapy that half-worked, homework that never got done, and a suspicion that they were bad at treatment. Usually they were not. The treatment had simply not been built for the way their attention actually works.
Related pages
Not sure whether this is the right fit?
Start with a free 30-minute call. We will talk through what is going on, I will tell you honestly whether I think I can help, and if I cannot I will try to point you to someone who can. There is no obligation and no charge.