What Is Obsessive-Compulsive Disorder (OCD)?

A person with OCD washing their hands

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Obsessive-compulsive disorder (OCD) is a mental health condition characterized by obsessions and compulsions that interfere with daily life.

OCD was formerly classified as an anxiety disorder because people affected by this mental illness often experience severe anxiety as a result of obsessive thoughts. They may also engage in extensive rituals in an attempt to reduce the anxiety caused by obsessions.

In the newest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), OCD was moved to its own disorder class of "Obsessive-Compulsive and Related Disorders." Related conditions in the class include body-dysmorphic disorder, hoarding disorder, and trichotillomania.

Symptoms of OCD

Symptoms of OCD usually appear gradually and can be long-lasting if not treated. People with OCD may experience symptoms of obsessions, compulsions, or both. Such symptoms interfere with many areas of life including school, work, relationships, and normal daily functioning.


Obsessions are thoughts, images, or ideas that won't go away, are unwanted, and are extremely distressing or worrying ("What if I become infected with a deadly disease?" or "What if I hurt someone?").

Some common symptoms of obsessions include:

  • Distressing violent thoughts or images
  • A need to have everything in a certain order
  • Fear of germs
  • Unwanted thoughts of forbidden or taboo topics such as sex or religion


Compulsions are behaviors that have to be done over and over again to relieve anxiety. Compulsions are often related to obsessions. For example, if you are obsessed with being contaminated, you might feel compelled to wash your hands repeatedly. However, this is not always the case.

Some common compulsions include:

  • Counting things over and over again
  • Excessive washing or cleaning
  • Ordering things in a particular or symmetrical way
  • Repeated checking (such as checking that the door is locked or that the oven is off)


It is important to be aware that not all habits or repetitive behaviors are synonymous with compulsions. Everyone has repeated thoughts or engages in double-checking things from time to time. In order to be diagnosed with OCD, their experience is characterized by:

  • An inability to control their thoughts or behaviors, even when they recognize that they are excessive or irrational
  • Spending an hour or more a day on these obsessions and compulsions
  • Experiencing significant distress or problems and disruptions in daily life because of these thoughts and behaviors

OCD is a relatively common disorder that by some estimates about 2.3% of people over their lifetime. It is experienced equally by men and women and affects all races and cultures.

OCD usually begins around late adolescence/young adulthood, although young children and teenagers can also be affected. Parents and teachers often miss OCD in young children and teenagers, as they may go to great lengths to hide their symptoms.


The exact causes of OCD are not known, but there are a few factors that are believed to play a role.

  • Biological factors: Abnormal neural circuits in the brain are associated with OCD. If you have OCD, certain parts of your brain may have difficulty inhibiting and "turning off" obsessive thoughts and impulses to turn off. As a result, you may experience obsessions and/or compulsions. The breakdown of this system may be related to serotonin and other neurotransmitter abnormalities.​
  • Family history: You may also be at greater risk if there is a family history of the disorder. Research has shown that if you, a parent, or a sibling have OCD, there is about a 25% chance that another first-degree family member will also have it.
  • Genetics: Although a single "OCD gene" has not been identified, OCD may be related to particular groups of genes.
  • Stress: Stress of all types including unemployment, relationship difficulties, problems at school, illness, or childbirth can be triggers for symptoms of OCD.

People who are vulnerable to OCD describe a strong need to control their thoughts and may believe that their obsessive thoughts mean they are going crazy or will lose control. While many people can have recurrent, strange or unusual thoughts when feeling stressed, if you are vulnerable to OCD, it may be difficult to ignore or forget about these thoughts. In fact, because these thoughts seem so dangerous, you end up paying even more attention to them, which sets up a vicious cycle.


Obsessive-compulsive disorder can present in a few different ways. Some people experience only obsessions, more commonly people experience both obsessions and compulsions, even if the compulsive behavior is only mental. There are no official subtypes of OCD, but research suggests that the most common obsessions and compulsions tend to center on certain themes:

  • Cleanliness or fear of contamination
  • A need for order, symmetry, or perfection
  • Taboo or forbidden thoughts
  • Potential harm to oneself or others

Parents should also be aware of a subtype of OCD in children triggered by certain infections such as strep throat, in which the child's own immune system attacks the brain. Pediatric Autoimmune Neuropsychiatric Disorders (PANDAS) associated with streptococcal infections by some estimates may account for up to 25% of the children who have OCD.

Unlike normal OCD, which develops slowly, in contrast to other forms of OCD, PANDAS OCD develops quickly and has a variety of other symptoms associated with it.


Treatments for OCD may include medications, psychotherapy, or a combination of the two.


There are a variety of medications that are effective in reducing the frequency and severity of OCD symptoms. Many of the medications that are effective in treating OCD, such as Prozac (fluoxetine), Paxil (paroxetine), Zoloft (sertraline), Anafranil (clomipramine), and Luvox (fluvoxamine) affect levels of serotonin. Additional types of medications that affect other neurotransmitters in the brain may also be used.


Psychological therapies are also highly effective treatments for reducing the frequency and intensity of OCD symptoms. Effective psychological treatments for OCD emphasize changes in behavior and/or thoughts.

When appropriate, psychotherapy can be done alone or combined with medication. The two main types of psychological therapies for OCD are cognitive behaviorial therapy (CBT) and exposure and response prevention (ERP) therapy.


OCD can be a chronic, long-lasting condition that may worsen with time, so it is important to get professional treatment. In addition to talking to your doctor or mental health professional, there are also a number of self-help strategies that you can use to help manage your symptoms:

  • Practice good self-care strategies that will help you cope with stress. Stress can often trigger OCD symptoms, so it is important to rely on effective and healthy coping methods. Research has shown that sleep disturbances are linked to more severe OCD symptoms. In addition to sleep, regular physical exercise and a healthy diet are lifestyle choices you can make that will make it easier to manage the stress and worries that life throws at you.
  • Try relaxation techniques. Add some effective tools such as meditation, deep breathing, visualization, and progressive muscle relaxation to your relaxation rituals.
  • Find support. Consider joining a support group such as those found on the International OCD Foundation's online support group website. Such groups can be helpful to talk to people who have had the same experiences as you. Social support is important for mental well-being, and support groups can be a helpful resource.

If you or a loved one are struggling with OCD, contact the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 for information on support and treatment facilities in your area.

For more mental health resources, see our National Helpline Database.

6 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute of Mental Health. Obsessive compulsive disorder.

  2. National Institute of Mental Health. Obsessive-compulsive disorder (OCD).

  3. Sinopoli VM, Burton CL, Kronenberg S, Arnold PD. A review of the role of serotonin system genes in obsessive-compulsive disorderNeurosci Biobehav Rev. 2017;80:372‐381. doi:10.1016/j.neubiorev.2017.05.029

  4. Hanna GL, Himle JA, Curtis GC, Gillespie BW. A family study of obsessive-compulsive disorder with pediatric probands. Am J Med Genet B Neuropsychiatr Genet. 2005;134B(1):13-9. doi:10.1002/ajmg.b.30138

  5. Leckman JF, Bloch MH, King RA. Symptom dimensions and subtypes of obsessive-compulsive disorder: A developmental perspectiveDialogues Clin Neurosci. 2009;11(1):21‐33.

  6. Paterson JL, Reynolds AC, Ferguson SA, Dawson D. Sleep and obsessive-compulsive disorder (OCD). Sleep Med Rev. 2013;17(6):465-74. doi:10.1016/j.smrv.2012.12.002

Additional Reading

By Owen Kelly, PhD
Owen Kelly, PhD, is a clinical psychologist, professor, and author in Ontario, ON, who specializes in anxiety and mood disorders.