First, the direct answer. If you have obsessive-compulsive disorder and the standard treatments have not been enough — a proper course of exposure and response prevention, an SSRI at adequate dose and duration, or both — you are not out of options, and the remaining ladder is longer than most people are told. It is also less psychedelic than the headlines suggest: for OCD, unlike depression, the established next steps are mostly refinements of the standard treatments — higher doses, longer courses, different combinations — plus, at the far end, one neurosurgical option with real evidence behind it. This guide walks the whole ladder, with what the evidence and the European guidelines actually say at each rung, and a sober account of where ketamine and psilocybin research stands.
One reassurance before the list. Partial response is the norm in OCD care, not the exception, and the reference guidelines this page leans on — the UK's NICE guideline CG31 and Germany's S3-Leitlinie for obsessive-compulsive disorders — plan explicitly for it, with defined steps after each treatment that has not worked. Nothing on this page is a recommendation of one option over another; which step fits you is a decision for you and a clinician who knows your history.
TL;DR CBT with exposure and response prevention (ERP) and SSRIs are the first-line OCD treatments in the UK and German guidelines — and both are frequently under-delivered, so the first question is whether you have truly had them: real ERP with a trained therapist, and an SSRI at the higher doses and longer durations OCD often needs. After that the guideline ladder continues: switching SSRIs, clomipramine, combining medication with ERP, and antipsychotic augmentation as a specialist step. For severe OCD that has resisted all of this, deep brain stimulation exists as a rare, specialist-centre neurosurgical option. Ketamine for OCD rests on one small crossover trial plus early studies — one trial is recruiting in Vienna. Psilocybin for OCD is US-led research; no European trial is currently recruiting. Every one of these doors opens with the same key: a written record of what you have tried.
What the options actually are
So much for the compressed version; here is the same ladder, rung by rung.
ERP — the first line, and the first thing to re-examine. Both reference guidelines put cognitive behavioural therapy including exposure and response prevention at the front of OCD treatment (NICE CG31; AWMF 038-017). ERP is a specific method — deliberately confronting the triggers of obsessions while not performing the compulsion, with a therapist trained in exactly this — and it is one of the most under-delivered treatments in psychiatry: general talking therapy, supportive counselling, or CBT that never included systematic exposure work is not ERP. If a course "didn't work", start by asking what was actually delivered, over how many sessions, and whether exposure exercises happened between them. A second course — with a therapist who specialises in OCD, in a different format, or at higher intensity, including inpatient or day-clinic ERP programmes in several European countries — is a standard guideline move, not an admission of failure.
SSRIs, done properly — higher doses, longer trials. SSRIs are the first-line medication for OCD in both guidelines, and OCD has its own pharmacological rules that non-specialists sometimes miss: response typically takes longer than in depression — up to 12 weeks — and the doses that work are often at the top of the licensed range (NICE CG31). A "failed" SSRI trial at a low dose for six weeks is not a failed trial by OCD standards. If one SSRI has genuinely not helped at an adequate dose and duration, switching to a different SSRI is the next rung; clomipramine — an older tricyclic with the strongest single-drug history in OCD — is the classic step after SSRIs, with more side effects and specialist monitoring. Combining medication with ERP rather than choosing between them is itself a guideline option, and for many situations the recommended one.
Augmentation — the established specialist step most people haven't heard of. When SSRIs at adequate dose and duration have brought partial or no response, adding a low-dose antipsychotic (such as risperidone or aripiprazole) to the SSRI is an evidence-based augmentation strategy, recommended in the guidelines as a specialist decision with monitoring (NICE CG31; AWMF 038-017). It helps a meaningful minority — roughly one person in three in the trial literature — which is worth knowing before rather than after you conclude that medication has nothing left to offer. This is exactly the stage where a referral to a psychiatrist with OCD experience, rather than another round with a generalist, changes what is on the table.
Deep brain stimulation — real, rare, and last on the ladder. For the severest OCD — chronic, disabling, resistant to multiple adequate courses of ERP and medication — deep brain stimulation (DBS) exists: electrodes implanted in defined brain targets, adjustable and reversible in the sense that stimulation can be switched off. This is genuine neurosurgery, performed in a handful of specialist centres in Europe, on small numbers of carefully selected patients, usually within research protocols or specialist commissioning. The evidence is encouraging for exactly this group: a 2025 individual-participant meta-analysis in Molecular Psychiatry found clinically meaningful improvement in around half of these otherwise treatment-refractory cases (Gadot et al. 2025). DBS is nobody's next step after two SSRIs; it is proof that the ladder does not end where most treatment histories stop.
Ketamine — early evidence. Ketamine's rapid effect in depression has made it a natural OCD candidate, but the evidence is thin: the key controlled study is a single randomised crossover trial in 15 unmedicated adults, which found rapid but short-lived reductions in obsessions after a single infusion (Rodriguez et al. 2013), surrounded by small open-label studies with mixed results. No regulator has approved ketamine or esketamine for OCD; esketamine's EU authorisation covers treatment-resistant depression only. Anyone offering ketamine as an established OCD treatment is ahead of the data. The research is moving, though, and in Europe: the Medical University of Vienna is currently recruiting for a trial of ketamine in obsessive-compulsive disorder (CTIS 2024-518212-40-00). Where ketamine's evidence is genuinely strong — depression — is covered in our ketamine evidence review; and if you also have depression that has failed two antidepressants, that is a separate assessment worth making, mapped in depression treatment isn't working: your options.
Psilocybin — a US research story, for now. Psilocybin for OCD has a long research pedigree — the first modern study dates to 2006 — and a currently active pipeline of small trials at Yale, Johns Hopkins, Arizona and Toronto, plus one study in Israel. In Europe the picture is sparse: a UK phase 1 feasibility study at Imperial College London (PsilOCD, NCT06258031) has completed, and as of September 2026 no European psilocybin trial for OCD is recruiting on either major registry. No regulator anywhere has approved psilocybin for any indication, so outside a trial there is no lawful psilocybin route for OCD in the EU — a clinic or retreat offering it is a red flag, not a head start. What the psilocybin evidence does and does not show in its best-studied indication is in our psilocybin evidence review.
How to work out where you are
First: what have you actually tried? Write it down, in one document: every course of therapy, with whether it included real exposure and response prevention, the number of sessions, and whether between-session exposure work happened; every medicine, with name, highest dose reached, weeks at that dose, effect and side effects; any augmentation; any inpatient or day-clinic treatment. Old letters and prescriptions are the raw material. In OCD this document matters even more than usual, because under-dosed and under-delivered first-line treatment is so common — the difference between "SSRIs don't work for me" and "I had one SSRI at a starting dose for six weeks" determines the entire next conversation.
Second: where are you now? Clinicians grade OCD severity with instruments like the Y-BOCS interview; there is no self-test that replaces that, but a written account of your current obsessions, compulsions and the hours they consume anchors an appointment. Depression travels with OCD often enough that it is worth checking separately — our eligibility check runs validated depression screeners privately in your browser, and if your low mood has independently failed to respond to two antidepressants, a door may be open on that side (depression options guide). If you are reading this for someone else, our guide for family members covers how to help without pushing — in OCD, that includes not participating in rituals, which is its own skill.
Trials as an option
For ketamine and psilocybin in OCD, trials are the only supervised route in Europe, and the pipeline is small. As of September 2026: the Medical University of Vienna is recruiting for ketamine therapy in obsessive-compulsive disorder (CTIS 2024-518212-40-00, authorised October 2024); the UK's PsilOCD feasibility study has completed (NCT06258031); and the active psilocybin OCD trials are in the US, Canada and Israel. Registries change faster than any page can: check ClinicalTrials.gov and the EU's CTIS register directly, and read our trials guide for how phases, placebo and consent work. The same ground rules apply: trials are free, voluntary and ethics-supervised; screening is strict and most applicants are screened out; and some psychedelic protocols require supervised tapering of serotonergic medication — for OCD that can mean the SSRI doing part of the work, a decision to weigh with your clinician, never alone.
Frequently asked questions
What helps with OCD when nothing works?
"Nothing works" almost always means "part of the ladder has been tried". The full guideline sequence — proper ERP, an SSRI at OCD-appropriate dose and duration, a second SSRI, clomipramine, ERP combined with medication, antipsychotic augmentation, intensive or inpatient ERP — is longer than most treatment histories. If you have genuinely worked through most of it, the remaining moves are a specialist OCD service reassessment and, for the severest cases, deep brain stimulation in a specialist centre. The right next appointment is with a psychiatrist or therapist who treats OCD specifically.
Is ketamine a treatment for OCD?
Not an established one. The controlled evidence is a single small crossover trial showing rapid but short-lived effects, plus small open studies with mixed results; no regulator has approved ketamine or esketamine for OCD, so any such use is off-label and ahead of the data. A European trial is recruiting at the Medical University of Vienna. Esketamine's EU approval covers treatment-resistant depression — relevant only if you separately have depression that has failed two antidepressants.
Can psilocybin cure OCD?
Nobody knows yet, and no regulator has approved it. The completed studies are small — the field's current trials, mostly phase 1 and 2, are running in the US, Canada and Israel; in Europe a UK feasibility study has completed and nothing is currently recruiting. There is no lawful psilocybin route for OCD in the EU outside a clinical trial.
Do I have to redo ERP if it didn't work the first time?
Nobody can oblige you — but before writing it off, check what was actually delivered. ERP means systematic, planned exposure with response prevention, and much of what is sold as CBT for OCD never includes it. A second course with an OCD specialist, at higher intensity or in a day-clinic format, is a standard guideline option with genuine response rates — and it is what OCD specialists themselves usually recommend before, and alongside, any medication escalation.
What if I also have depression?
Common, and worth treating as its own track. Depression alongside OCD can blunt ERP and needs its own assessment; and if your depression has separately failed two adequate antidepressant courses, the treatment-resistant depression pathway — including EU-approved esketamine — may be open on that side. Our depression options guide maps that ladder, and our eligibility check tells you which routes are realistic in your country.
Sources
- NICE CG31 — Obsessive-compulsive disorder and body dysmorphic disorder: treatment
- AWMF 038-017 — S3-Leitlinie Zwangsstörungen
- Rodriguez CI et al. Randomized controlled crossover trial of ketamine in obsessive-compulsive disorder. Neuropsychopharmacology 2013
- Gadot R et al. Deep brain stimulation for obsessive-compulsive disorder: individual-participant meta-analysis. Molecular Psychiatry 2025
- ClinicalTrials.gov — NCT06258031, PsilOCD feasibility study (Imperial College London)
- CTIS — the EU Clinical Trials Information System
- EMA — Spravato European Public Assessment Report (indication: treatment-resistant depression)
This guide is for general information only and is not medical advice, a diagnosis, or a recommendation of any treatment. It does not describe doses, preparation or session experiences, and it is not a guide to obtaining any substance. Discuss your options with a licensed clinician who knows your history. If you are in crisis, contact your local emergency number (112 in the EU) or a crisis line immediately.