For adults

OCD in adults

OCD responds well to the right therapy. In research trials, around half to two thirds of people who complete ERP respond, fewer recover fully, and many are left with some symptoms (Öst and colleagues, 2015). This page explains what keeps OCD going and what changes it.

What OCD is

OCD has two parts. An obsession is an unwanted thought, image, urge or doubt that arrives uninvited and causes distress. A compulsion is anything you do to make that distress go away, whether it is visible, such as washing or checking, or happens in your head, such as reviewing a memory or silently reassuring yourself. The compulsion brings relief for a short time, and the relief teaches your brain that the thought was a real threat and the ritual kept you safe, so the next thought arrives with more force. Many compulsions are hidden, such as rereading an email six times before sending it, replaying a conversation from three days ago looking for something unforgivable, or avoiding being alone with your own child, and OCD like this can be mistaken for a character flaw rather than a treatable condition.

The themes include contamination, harm, symmetry and things feeling “just right”, religious or moral worry, unwanted sexual or violent thoughts, doubts about a relationship or your sexual orientation, and fear of being responsible for something terrible. The cycle of doubt, compulsion and short-lived relief is the same whatever the theme, which is why the treatment is the same too. Each theme is described on the types of OCD page.

The OCD loop

1. Trigger: Turning the hob off, or locking the front door
2. Obsession: What if I left it on and the house burns down?
3. Feeling: Anxiety, and a doubt that will not settle
4. Compulsion: Going back to check, again and again
5. Relief, for now: Calmer for a while, then the doubt returns
6. Then back to the first step, and the loop runs again.
7. Other situations that now set it off too: Locking up at night, leaving the house, A knock at the door, going to bed.

Where treatment steps in. You face the trigger in planned steps and do not do the compulsion, and learn that you can carry the anxiety and the doubt without it.

New triggers. Over time, more situations become linked to the trigger and start the loop off too.

The treatment that works

The treatment with the strongest evidence is exposure and response prevention (ERP), a specific form of CBT, and NICE recommends CBT including ERP as a first-line psychological treatment for OCD in adults. Exposure means deliberately facing the thought or situation that sets off the doubt, and response prevention means not doing the compulsion afterwards. We map what triggers the doubt, what you do about it, what you avoid, and who else has been drawn into giving reassurance. Then we build a list of situations together and you practise them without the ritual, starting with a step that feels manageable and mixing easier and harder steps as you go. The anxiety rises and you let it be there without trying to fix it. It often eases, but the practice counts even when it does not. The main thing you learn is that you can handle the anxiety and the uncertainty without the compulsion, and noticing that the feared outcome did not happen comes second to that.

Most of the change happens between sessions, in practice such as sending an email once, leaving the house without the final check, or deliberately thinking a thought you have spent years pushing away. Each step is agreed in advance and it becomes easier the more you do it. The exposure planner and practice log I use for this are free on the resources page.

Why general CBT can struggle with OCD

Weighing the evidence for a thought, or reasoning your way to why it is unlikely, gives the same brief sense of being settled that a compulsion gives, and OCD can turn it into a new ritual. ERP works on what you do when the thought arrives rather than on its content. If earlier therapy focused on the content of your thoughts and did not help, that does not mean your OCD is untreatable.

OCD alongside ADHD

OCD and ADHD occur together more often than chance would predict, although studies disagree on how often, and each can hide the other. A mental compulsion, such as rereading a line until it feels right, looks like inattention from the outside. ERP also asks for things that ADHD can make harder, such as holding a plan in mind while the urge is strong, organising practice between sessions, and working towards a benefit that arrives weeks later, so I ask about both in the first session.

The principles of ERP stay the same and I adapt how it is delivered. Practice is shorter and more frequent, with several exposures of five or ten minutes across the week rather than one long one. The plan is written down in your own words and kept on your phone or somewhere you will see it, tied to a fixed time and place. We work on fewer targets at a time, each session ends with a written summary, and we build in a small reward soon after practice. These adaptations are drawn from what is known about ADHD and have not been tested together in trials.

I do not assess or diagnose ADHD. I treat OCD and anxiety in people whose ADHD is diagnosed, being assessed or suspected, and where an assessment is needed I will say so. Questions about ADHD medication, including whether a stimulant is affecting your OCD, are for your prescriber.

Sources

• Öst, L.-G., Havnen, A., Hansen, B., & Kvale, G. (2015). Cognitive behavioral treatments of obsessive-compulsive disorder: A systematic review and meta-analysis of studies published 1993-2014. Clinical Psychology Review, 40, 156-169. doi.org/10.1016/j.cpr.2015.06.003 (opens in a new tab)

Common questions

Written by Dr Daniel O’Rourke, PhD, ABPP, CPsychol, HCPC-registered Clinical Psychologist Last reviewed: September 2026