Diagnosing and treating obsessive-compulsive disorder

Uma Chatterjee has had unwanted, distressing thoughts for as long as she can remember. As a child, she repeated a series of prayers 39 times, hoping to keep her parents safe. As a young adult, fear of financial ruin sometimes kept her in the grocery store for 8 hours comparing prices. But she was not diagnosed with obsessive-compulsive disorder (OCD) until age 22 and did not receive the recommended treatment until age 25.

Chatterjee’s story is not uncommon. OCD affects nearly 10 million people in the United States, but more than 80% of cases are estimated to be undiagnosed, according to an analysis of more than 10 million electronic health records. Of those with a diagnosis, as few as 2% may be receiving the recommended treatment (Deusser, R. et al., America’s OCD Care Crisis, International OCD Foundation [IOCDF], 2025opens in new window). Research suggests that, on average, people with OCD have symptoms for nearly 13 years before they are correctly diagnosed (Ziegler, S. et al., PLOS One, Vol. 16, No. 12, 2021opens in new window).

“Patients with OCD often suffer for many years before receiving an accurate diagnosis, sometimes getting treatments that perpetuate the condition or—even worse—being hospitalized when they disclose scary intrusive thoughts that are misinterpreted as indicating suicidality or homicidality,” said Tamar Gordon, PhD, a licensed clinical psychologist specializing in OCD who founded and directs Gordon Therapy Group in New York City.

Misdiagnosis and underdiagnosis are largely due to misconceptions about OCD, both by the public and among health care providers, as well as insufficient training to help clinicians distinguish it from other conditions, such as generalized anxiety disorder (GAD), post-traumatic stress disorder (PTSD), and psychotic disorders. Many people living with OCD struggle in silence, either too ashamed to disclose obsessions or not realizing that something is wrong.

Compared with the general population, people with OCD face a suicide rate that is nearly 5 times higher and an 82% higher rate of premature death (Fernández de la Cruz, L. et al., BMJ, Vol. 384, 2024opens in new window). Better understanding of how to screen for, diagnose, and treat OCD is a critical step toward connecting these individuals with potentially life-saving care.

“Providers don’t need to specialize in OCD to be able to help,” said Chatterjee, who is now conducting research on OCD as a neuroscience doctoral student at the University of Wisconsin–Madison and advocating for improved recognition of the condition. “By questioning what they know about this condition and continuing to learn about it, they have tremendous power to relieve the hopelessness and pain that many people with OCD are secretly living with.”

Popular understanding of OCD often reduces the condition to a strong preference for order or cleanliness. In reality, it is a distressing and often debilitating disorder that can span many different themes, from contamination concerns and repeated checking to intrusive moral, sexual, or ­relationship-related concerns.

People with OCD experience obsessions—persistent and intrusive thoughts, urges, or images—that cause significant distress or anxiety, often by triggering intense doubt, guilt, or shame. To reduce that distress, they perform compulsions—repetitive behaviors or mental acts—that are not realistically connected to the feared outcome they aim to prevent but are instead a way to gain certainty and relieve doubt. The obsessions or compulsions are either time-consuming, cause significant distress or impairment, or both.

Distress is often anxiety, but can also include disgust, obsessional guilt (guilty feelings about something that has not occurred), or “not just right experiences,” which are overwhelming feelings that something is wrong. Some people have the same intrusive thoughts every day, while others have thoughts that change.

OCD can occur at any age, but it typically starts between ages 7 and 12 or between the late teen and early adult years, around age 20. Prevalence rates do not differ substantially across sexes, races, or ethnicities (“About OCD,” IOCDFopens in new window). Severity can range from mild, with manageable symptoms that cause little daily disruption, to extreme, with symptoms that are incapacitating.

Many people with OCD experience intrusive thoughts that are horrific or taboo, such as the fear they may kill themselves, harm a loved one, or sexually harm a child in their care. Importantly, these thoughts are ego-dystonic, or inconsistent with a person’s values or identity (as opposed to ego-syntonic thoughts or urges, which feel acceptable or desirable). Distinguishing between the two is critical, because people with OCD are sometimes unnecessarily hospitalized or reported to authorities after sharing ego-dystonic thoughts they have no intention of acting on.

“Clinicians need to know what intrusive thoughts are and how to identify them—and they need to be comfortable discussing taboo topics,” Gordon said.

Compulsions (sometimes called rituals) can be behavioral, such as repeatedly checking locks, but they can also be covert and internal. Covert compulsions include rumination, silent counting or praying, neutralizing a “bad” thought with a “good” one, or mentally reviewing memories to ensure something bad did not happen.

“Rituals may look like things many of us do on a day-to-day basis, but they tend to be extreme in nature, and the primary goal is to get rid of an internal feeling,” said Nathaniel Van Kirk, PhD, a licensed clinical psychologist and program director of the OCD Institute at McLean Hospital in Belmont, Massachusetts. “Performing rituals actually reinforces obsessions—making them more intense, more frequent, and harder to [tolerate].”

Though OCD is not classified into formal subtypes, it presents in several common symptom themes. These include contamination (where a fear of germs or toxins leads to excessive cleaning or avoidance of certain places), harm (where a fear of causing injury to self or others leads to repeated checking of memories,  objects, or situations), not just right experiences (where things feel uneven, incomplete, or not quite right), sexual taboos (fear that one will act in an unacceptable sexual manner, leading to avoidance or mental checking), and scrupulosity (excessive concerns about blasphemy or religious wrongdoing).

Primary-care providers and mental health clinicians can help identify people who may have OCD using brief scales such as the OCI-4, a four-item version of the ­obsessive-compulsive inventory scale, or simply by routinely asking patients whether they have intrusive thoughts, said Dean McKay, PhD, a professor of psychology at Fordham University and a clinician specializing in OCD (Journal of Anxiety Disordersopens in new window, Vol. 78, 2021opens in new window). Patients can then be referred to a trained provider for in-depth assessment.

Diagnosing OCD requires distinguishing obsessions—intrusive, unwanted thoughts, images, or urges that cause significant distress or anxiety—from worries, such as concerns about finances or social responsibilities. Clinicians must also assess the presence of compulsions and the extent to which they interfere with daily functioning. Central to diagnosis is identifying whether compulsive behaviors are performed in direct response to obsessions.

“If clinicians focus on the content of a ritual rather than the purpose it serves, OCD can be overlooked,” Van Kirk said. “Compulsions can take many forms, but they are defined by their function—efforts to reduce distress or neutralize unwanted thoughts and obsessional fears.”

OCD is often missed because, on the surface, it can look like several other conditions. GAD is among the most common, because obsessions often cause significant anxiety. Seeking safety from intrusive thoughts can also look like PTSD, which can co-occur with and complicate OCD. Because obsessions can seem fantastical, they may also be confused with delusions, leading to a misdiagnosis of schizophrenia or another psychotic disorder.

Treatments for GAD can involve cognitive strategies aimed at reducing perceived threat or increasing a sense of safety. With OCD, however, providing reassurance is counterproductive. While it may briefly lower distress, reassurance functions like a compulsion, reinforcing a patient’s drive to seek certainty. When applied to OCD, cognitive behavioral therapies not specifically designed for the condition may therefore worsen symptoms, according to work by McKay (Clinical Psychology: Science and Practiceopens in new window, Vol. 28, No. 1, 2021opens in new window).

In children, OCD can be mistaken for attention-deficit/hyperactivity disorder. One young patient of Gordon’s feared forgetting things, so he repeatedly checked his backpack to make sure each item was in place, leading to inattention at school.

“Autism spectrum disorders can also involve repetitive thoughts and behaviors, but a key distinction is that these interests are pleasant or ego-syntonic or used as a way to regulate the nervous system, whereas obsessions are unpleasant and frightening,” said Fred Penzel, PhD, a licensed clinical psychologist and expert in treating OCD who founded and directs Western Suffolk Psychological Services in Huntington, New York.

Experts do not all agree on what conditions are related to OCD on a fundamental level. The latest edition of the Diagnostic and Statistical Manual of Mental Disorders, the DSM-5, lists several related conditions, including hoarding disorderopens in new window (where people have difficulty discarding possessions) and body dysmorphic disorder (where people are preoccupied with perceived flaws in their physical appearance). Many also believe that illness anxiety disorder, formerly called hypochondriasis, bears key similarities to OCD. There is also evidence for substantial overlap between OCD and Tourette syndrome (Mansueto, C. S., “OCD and Tourette Syndrome: Re-examining the Relationship,” IOCDF, 2008).

Exposure and response prevention (ERP), a specialized form of cognitive behavioral therapy developed for treating OCD in the 1960s, remains the first-line treatment. Estimates from research studies and clinical experts suggest that between 65% and 80% of patients respond well to ERP, while others partially benefit or do not benefit (Ong, C. W., et al., Journal of Anxiety Disorders, Vol. 40, 2016opens in new window).

During ERP, a trained clinician guides a patient to systematically face what they fear in growing degrees of intensity while resisting performing the rituals they typically use to neutralize those fears. By doing so, patients gradually increase their tolerance for uncertainty and learn to coexist with their intrusive thoughts.

“Patients learn that it’s possible to have the thought and carry on with life rather than twisting themselves out of shape to avoid feeling fear,” Penzel said.

While the underlying principles do not change, treatment with ERP can take on many forms depending on a patient’s symptoms. A clinician might guide someone with ­contamination-related OCD to touch doorknobs or shake hands with another person. For a person with intrusive thoughts about suicide, treatment may involve imaginal scripts that ask the patient to sit with feared scenarios—such as handling knives—without attempting to neutralize or escape their distress. After completing a course of ERP, patients learn strategies to manage symptoms on their own, with follow-up or booster sessions recommended to maintain progress over time.

ERP can be adapted for children by including game-like elements, such as incentives tied to completing exposures, said C. Alec Pollard, PhD, a licensed clinical psychologist and founding director of the Center for OCD and Anxiety-Related Disorders at St. Louis Behavioral Medicine Institute. Providers also work closely with parents to reduce accommodation, or behaviors that unintentionally reinforce a child’s symptoms, such as doing extra laundry to assuage contamination fears.

Misconceptions about ERP include the belief that it is too distressing to undergo, and some people with OCD avoid seeking help because they fear the treatment will be intolerable. But when delivered correctly by a trained provider—such as those recommended by the International OCD Foundationopens in new window, a leading global authority on the condition—ERP “is probably the most compassionate thing you can do for someone who suffers from OCD,” McKay said.

Selective serotonin reuptake inhibitors (SSRIs) are also effective in reducing OCD symptoms and are typically prescribed in higher doses than used to treat depression. Research suggests that about half of patients with OCD respond to SSRIs, with a 40% to 50% decrease in symptom severity (Poskar, S., “Medication Treatment for Obsessive Compulsive Disorder in Adults,” IOCDF). Most psychologists view SSRIs as a way to enhance ERP rather than as a standalone treatment.

“Medication is a good way to turn down the volume on the OCD—reducing distress enough for patients to engage in ERP,” Van Kirk said. In severe or extreme cases of OCD, other medications, such as antipsychotics, may also be helpful.

Several tailored cognitive therapies can be used to augment ERP. These include addressing the ­over-importance of thoughts (placing excessive weight on intrusive or fantastical thoughts), thought-action fusion (the belief that thinking about an event makes it more likely to happen), and overestimation of threat (the belief that one faces greater risks than others).

Acceptance and commitment therapy can also help patients engage more fully with ERP, Gordon said, by providing tools for tolerating uncertainty and distress. In some cases, she also teaches coping skills—such as mindfulness and grounding exercises—to help patients stay with exposures. Not all providers use coping skills because some view them as bordering on reassurance.

A new treatment approach known as inference-based cognitive behavioral therapy (I-CBT) may offer a further adjunct to ERP or an alternative for patients unwilling to do ERP. This metacognitive approach focuses “upstream” on how obsessions form, teaching patients to question the faulty reasoning that gives rise to them. In a randomized controlled trial, I-CBT led to symptom improvement comparable with other cognitive behavioral treatments that included ERP (Aardema, F. et al., Psychotherapy and Psychosomatics, Vol. 91, No. 5, 2022opens in new window).

Ongoing research aims to make ERP more effective across the board, including by finding ways to help the roughly 40% of patients who do not respond adequately. A new line of inquiry also seeks to understand how past trauma can complicate or exacerbate OCD, as well as how to respond to it. Chatterjee is among those using human brain tissue and animal models to identify neurobiological targets for treatment (specific brain-based mechanisms that therapies or medications could act on to reduce OCD symptoms), an area where options remain limited.

“OCD is severely underfunded and understudied—even compared with other mental health conditions,” Chatterjee said. “There are many people who aren’t helped, or helped enough, by existing treatments. We need more research into the biology of OCD for those who continue to struggle.”