Exposure and Response Prevention for OCD: What Sessions Look Like

Exposure and response prevention (ERP) is the form of cognitive behavioral therapy that the International OCD Foundation calls the most important for obsessive-compulsive disorder. In sessions, you and a trained therapist build a ranked list of situations that trigger your obsessions, then you practice facing them, starting with easier ones, while choosing not to perform the compulsion. Between sessions you repeat the practice on your own.

A standard course described by the Society of Clinical Psychology (APA Division 12) is approximately 12 sessions, and Division 12 rates ERP for OCD as having strong research support. Many people need more, and intensive formats exist. The first sessions are mostly assessment and planning; exposures usually start once you understand the rationale and agree to the plan.

How ERP works

The exposure part of ERP means practicing contact with the thoughts, images, objects and situations that make you anxious or set off obsessions. The response prevention part means choosing not to do the compulsive behavior once the anxiety or obsession has been triggered. Compulsions bring short-term relief, which is why they persist; they also keep the fear in place, because you never learn what happens without them.

The older explanation for why ERP works is that anxiety falls as you stay in the situation. Division 12's summary reflects that view: as people confront fears and stop escaping, their anxiety eventually reduces. Newer research on inhibitory learning emphasizes something slightly different, proposing that exposures may work better when they violate your expectation of what will happen, are varied, happen in more than one setting, and drop safety behaviors. In practice, that means a good therapist will not require your anxiety to drop to zero before an exposure ends, and will help you design practice that tests your specific fear.

Step 1: Assessment and the treatment plan

The first one or two sessions map your OCD in detail: what the obsessions are, what you do to neutralize them, what you avoid, and how much time and functioning it costs. Your clinician may rate severity with a standardized measure such as the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), the main outcome measure in large ERP trials, and repeat it to track progress.

Expect questions about compulsions that are easy to miss:

• Mental rituals, such as replaying events, counting, praying in a set way or mentally "cancelling" a thought. UK guidance recommends that ERP for people without visible compulsions target these mental rituals and neutralizing strategies.
• Reassurance seeking, from family, partners, search engines or the therapist.
• Avoidance, which can look like preference ("I just don't like public restrooms").
• Family involvement in rituals, such as a partner who answers the same question repeatedly or a parent who washes items for a child.

You should leave this stage understanding why ERP is being recommended and what you are agreeing to. You decide what you practice; a therapist should never surprise you with an exposure you have not agreed to.

Step 2: Building the exposure hierarchy

A hierarchy (sometimes called a ladder) lists situations from mildly to severely distressing, usually rated on a distress scale. Here is a simplified example for contamination fears.

Hierarchies for other OCD themes look different. For harm obsessions, exposures might involve holding a kitchen knife while a family member is nearby, or writing out a feared thought. For checking, they might involve leaving the house after locking the door once. For intrusive thoughts with no visible ritual, exposures often use written scripts or recordings of the feared thought, with response prevention aimed at mental rituals.

Step 3: What an exposure session looks like

1. Review of the past week's practice, including what was hard and any rituals that slipped in.
2. Choosing the next exposure from the hierarchy, and naming what you predict will happen.
3. Doing the exposure in session with the therapist coaching you to stay in contact with the trigger and the discomfort, without rituals.
4. Reviewing what you learned, especially how the outcome compared with your prediction.
5. Planning homework: the same or similar exposures, repeated daily or as agreed.

Some exposures cannot happen in an office. The International OCD Foundation advises asking prospective therapists whether they are willing to leave the office for exposure work, because it is sometimes necessary. Telehealth can help here, since exposures can be done in your own home or neighborhood with the therapist on video.

Step 4: Homework and response prevention between sessions

Most of the change in ERP happens between sessions. Early on, the therapist guides the work; over time you learn to design and do your own exposures. Response prevention is often the harder half. Plans usually spell out exactly which rituals you will drop or delay, and how to handle urges. If family members have become involved in rituals or reassurance, UK guidance recommends that the treatment plan help them reduce that involvement in a sensitive and supportive way.

Being honest about rituals that continue is more useful than reporting perfect compliance. A therapist can only adjust the plan when they know what is actually happening.

How long ERP takes, and the formats available

A meta-analysis of 16 randomized trials of CBT for OCD found that it outperformed control conditions, and that the effect did not depend on the number of sessions, baseline OCD severity or depression severity in the studies reviewed. That does not mean the number of sessions does not matter for you; it means people with more severe symptoms were not shown to benefit less. If you need a more structured setting, the guide to levels of mental health care explains intensive outpatient and residential options.

When to add medication

ERP and medication are both first-line options, and the choice depends on severity, preference and access. UK guidance offers adults with moderate impairment, or with mild impairment when low-intensity treatment has not been enough, the choice of an SSRI or more intensive CBT including ERP, as they appear comparably effective, and recommends combining the two when impairment is severe. For OCD that responds only partly to medication, a randomized trial found that adding ERP to a serotonin reuptake inhibitor worked better than adding risperidone or placebo, and its authors recommended offering ERP before an antipsychotic.

In a trial of adults comparing intensive ERP, clomipramine and the combination, ERP alone and ERP plus clomipramine both did better than clomipramine alone, and the two ERP groups did not differ. SSRIs such as fluoxetine are FDA-approved for OCD, and like all antidepressants they carry a boxed warning about increased suicidal thoughts and behaviors in children, adolescents and young adults. Whether to start, adjust or stop a medication is a decision for you and your prescriber. Never stop a medication on your own because ERP is going well. For a comparison of specific medications, see OCD treatment options compared and fluoxetine versus sertraline.

If you are thinking about suicide or are in crisis, call or text 988 (the 988 Suicide & Crisis Lifeline) or go to the nearest emergency room.

ERP for children and teens

For children, ERP is adapted to developmental age and involves parents or carers. Parents usually learn how to step back from accommodating rituals and how to coach their child through practice at home. In the Pediatric OCD Treatment Study, 112 children and teens aged 7 to 17 received CBT, sertraline, both, or placebo for 12 weeks; combined treatment outperformed either alone, and the authors recommended starting with combined treatment or CBT alone. For related anxiety care in children, see child anxiety treatment options.

Finding a clinician trained in ERP

A therapist who lists OCD among many specialties may not actually offer ERP, so ask. The International OCD Foundation's Resource Directory lists OCD specialists by location, including those who offer teletherapy. The foundation suggests asking these questions before you start:

• What techniques do you use to treat OCD? Be cautious if the answer is vague or does not mention CBT or ERP.
• Are you familiar with exposure and response prevention?
• What is your training and background in treating OCD? Membership in the IOCDF or the Association for Behavioral and Cognitive Therapies, and specialized training such as the IOCDF's Behavior Therapy Training Institute, are positive signs.
• How much of your practice involves OCD? The foundation suggests over 25% as a sign of specialization, though not as a strict rule.
• What is your attitude toward medication? A therapist who is negative about it is a warning sign.
• Are you willing to leave the office for exposures, and do you include families in treatment?

The foundation also notes that talk therapy that focuses only on insight has not been shown effective for OCD, and that ERP or medication should be tried first. That is one reason the comparison in CBT versus psychodynamic therapy comes out differently for OCD than for depression. ACT can be a useful companion to ERP for some people; see ACT versus CBT.

What progress looks like, and when to reassess

Progress in ERP is rarely a straight line. A typical pattern is that the first exposures feel hard, the same exposures become noticeably easier with repetition, and you gradually take on items higher on the hierarchy. Signs that treatment is working include spending less time on rituals, avoiding fewer places and activities, needing less reassurance, and getting back time for work, relationships and rest. A repeat severity rating, such as the Y-BOCS used in the trials, gives you and your therapist an objective check.

It is reasonable to reassess the plan with your therapist if, after several weeks of consistent practice, nothing has changed. Useful questions include whether response prevention is complete, whether new rituals or avoidance have replaced old ones, whether depression or another condition is getting in the way, and whether adding medication or moving to a more intensive format makes sense. The guide on signs your treatment isn't working covers how to raise this.

Toward the end of treatment, UK guidance recommends that clinicians explain how to apply the principles you learned if the same or new symptoms return. Keeping a written relapse plan, with your hierarchy and the early signs of rituals creeping back, makes that easier.

Common worries about starting ERP

• "It will be unbearable." Exposures start where you choose and build gradually. Discomfort is expected; overwhelming distress is a sign to adjust the plan.
• "What if my fear comes true?" Exposures are designed to be safe and within ordinary life. They target the uncertainty, not real danger.
• "My OCD is only in my head." ERP works with mental rituals too, using exposures to feared thoughts.
• "I tried exposure and it did not work." Check whether response prevention was included, whether practice happened between sessions, and whether mental rituals or reassurance continued during exposures.

How this fits with care at Dr. Lewis's practice

The practice's ongoing care includes psychiatric evaluation and medication management, psychotherapy including CBT and DBT, coaching, and nutrition and lifestyle psychiatry. With psychiatrists, psychiatric nurse practitioners and psychotherapists on one team, therapy and medication decisions for OCD can be coordinated. The site's OCD page and CBT page have more background. If ERP specifically is what you need, ask about it on the free discovery call so the team can tell you whether it fits or point you elsewhere. All guides in this series are collected in the guide to choosing psychiatric care.

Frequently asked questions

Is ERP the same as CBT?

ERP is a specific form of CBT. The International OCD Foundation calls it the most important type of CBT for OCD. A therapist who offers general CBT may not offer ERP, so ask directly.

Does ERP work for 'Pure O' or intrusive thoughts without visible rituals?

Yes. UK guidance recommends that, for obsessive thoughts without visible compulsions, CBT include exposure to the thoughts themselves and response prevention of mental rituals and neutralizing strategies, such as reviewing, cancelling a thought or seeking reassurance. Written scripts or recordings of the feared thought are common exposure tools.

Can ERP be done by telehealth?

Yes. The International OCD Foundation's directory includes teletherapy providers, and video sessions can make it easier to do exposures at home or in the places where symptoms happen.

Should my family be involved?

Often, yes, especially when family members answer reassurance questions or help with rituals. UK guidance recommends helping them reduce that involvement supportively, and for children, involving parents is standard.

What if I start ERP and feel worse at first?

A temporary rise in anxiety during exposures is expected. Tell your therapist if distress feels unmanageable or if depression worsens, so the plan can be adjusted. If you have thoughts of suicide, call or text 988 or go to an emergency room.

Will I need ERP forever?

No. The goal is for you to learn to do your own exposures. Toward the end of treatment, a therapist should help you plan how to apply the same skills if symptoms return.

Sources

1. Exposure and Response Prevention (ERP). International OCD Foundation, 2026. iocdf.org
2. How to Find the Right Therapist. International OCD Foundation, 2026. iocdf.org
3. Exposure and Response Prevention for Obsessive-Compulsive Disorder. Society of Clinical Psychology (APA Division 12), 2024. div12.org
4. Obsessive-compulsive disorder and body dysmorphic disorder: treatment (CG31), Recommendations. National Institute for Health and Care Excellence, 2005. nice.org.uk
5. Randomized, placebo-controlled trial of exposure and ritual prevention, clomipramine, and their combination in the treatment of obsessive-compulsive disorder. American Journal of Psychiatry (Foa et al.), 2005. pubmed.ncbi.nlm.nih.gov
6. Cognitive-behavioral therapy vs risperidone for augmenting serotonin reuptake inhibitors in obsessive-compulsive disorder: a randomized clinical trial. JAMA Psychiatry (Simpson et al.), 2013. pubmed.ncbi.nlm.nih.gov
7. Maximizing exposure therapy: an inhibitory learning approach. Behaviour Research and Therapy (Craske et al.), 2014. pubmed.ncbi.nlm.nih.gov
8. Cognitive-behavioral therapy for obsessive-compulsive disorder: a meta-analysis of treatment outcome and moderators. Journal of Psychiatric Research (Olatunji et al.), 2013. pubmed.ncbi.nlm.nih.gov
9. Cognitive-behavior therapy, sertraline, and their combination for children and adolescents with obsessive-compulsive disorder: the Pediatric OCD Treatment Study (POTS) randomized controlled trial. JAMA (POTS Team), 2004. pubmed.ncbi.nlm.nih.gov
10. PROZAC (fluoxetine capsules) prescribing information. DailyMed / U.S. FDA label, 2023. dailymed.nlm.nih.gov

Educational information, not medical, tax or legal advice. Decisions about diagnosis, medication and treatment belong with a clinician who knows your history.