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Obsessive-Compulsive Disorder (OCD)

Condition Basics

What is obsessive-compulsive disorder (OCD)?

Obsessive-compulsive disorder (OCD) is a mental health condition that causes repeated unwanted thoughts. To get rid of them, you may do the same tasks over and over. For example, if you fear that everything you touch has germs on it, you may wash your hands repeatedly to ease your fear.

What causes it?

Experts don't know the exact cause of OCD. There may be a problem with the way one part of the brain sends information to another part. Not having enough of a brain chemical called serotonin may be part of the problem.

What are the symptoms?

Obsessions and compulsions are key symptoms of OCD. Obsessions are unwanted thoughts, ideas, and impulses. They won't go away. Compulsions are behaviours that you repeat to try to control the obsessions. The symptoms usually take up a lot of time, more than 1 hour a day.

How is it diagnosed?

Your doctor can check for OCD by asking about your symptoms and your past health. A physical exam may also be done. You may also get a mental health assessment. This is a check of your emotions and how you think, reason, and remember.

How is OCD treated?

Treatment for OCD includes counselling and medicines. Using both tends to work best.

Counselling includes a type of cognitive behavioural therapy called exposure and response prevention (ERP). ERP slowly increases your contact with the thing that causes worries or anxiety. With the help of a counsellor, ERP can reduce your symptoms over time.

Antidepressant medicines called selective serotonin reuptake inhibitors (SSRIs) are most often used. Antidepressants work differently for everyone. Your doctor will help find the medicine and dose that works best for you.

Treatment can make your symptoms less severe. But you may still have some mild symptoms after you start treatment.

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Symptoms of OCD include:


These are unwanted thoughts, ideas, and impulses that you have again and again. They won't go away. Examples include:

  • A driving need to do things perfectly or correctly.
  • A fear of getting dirty or infected.

These are behaviours that you repeat to try to control the obsessions. Examples include:

  • Washing, or checking that something has been done.
  • Counting, often while doing another compulsive action, such as handwashing.

The obsessions or compulsions usually take up a lot of time—more than 1 hour a day.


What Happens

With OCD, you have disturbing, obsessive thoughts that cause fear or anxiety. To get rid of these thoughts and relieve the fear, you perform rituals, such as repeated handwashing or checking that something has been done. But the relief is only temporary. The thoughts come back, and you repeat the rituals.

The rituals or behaviours take up a lot of time. They have a big impact on your daily life. If your fear involves unfamiliar situations, you may be so obsessed by the fears that you stop going outside of your home. OCD can lower your quality of life because it affects your ability to work and have relationships.

Treatment, such as counselling and medicines, can reduce the symptoms of OCD.

Examinations and Tests

Your doctor can check for OCD by asking about your symptoms and your past health. A physical exam may also be done. And you may also get a mental health assessment. This is a check of your emotions and how well you can think, reason, and remember. You may be given written or verbal tests. The doctor may also look at your appearance, your mood, your behaviour, and how you express yourself.

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Treatment Overview

Treatment for OCD includes counselling and medicines. Depending on how bad your symptoms are, your doctor may prescribe only counselling, or you may have both counselling and medicine. Using both tends to works best.

The sooner you get treatment, the better. Early treatment can reduce symptoms and make the illness less disruptive in your life.


Exposure and response prevention (ERP) therapy works well to treat OCD. With ERP, you are exposed to an obsession, such as something you fear is dirty, over and over again. Each time, you try not to do the compulsive action that goes with it. In this case, the act would be washing your hands. ERP helps break the link between your obsessive thoughts and compulsive actions. You repeat this process every day for several weeks or months. You keep doing it until you are less anxious and you don't feel the need to do the compulsive action in response to the obsessive thought.

When you start ERP, your therapist may ask you to write a list of your obsessions, your actions (compulsions), and the things that you avoid. Then you'll rank them by how much anxiety they cause. You might start working on one that causes moderate anxiety. Then you would work your way up the list to the one that causes the most anxiety.

Therapists often combine ERP with cognitive behavioural therapy (CBT) to help stop the false beliefs that lead to OCD behaviours.


After you are diagnosed with OCD, your doctor will likely prescribe antidepressants known as selective serotonin reuptake inhibitors (SSRIs). These medicines are thought to help balance neurotransmitters (such as serotonin) in your brain.

Examples of SSRIs are:

  • Fluoxetine (Prozac).
  • Fluvoxamine (Luvox).
  • Sertraline (Zoloft).

Antidepressants help relieve obsessive thoughts and compulsive behaviours. They increase the level of serotonin in the brain. This helps regulate the communication between different parts of the brain.

In some cases, it takes time to adjust the dosage or find the right medicine that will work for you. You may start to feel better within 1 to 3 weeks after you start to take an SSRI. But it can take as many as 12 weeks to see more improvement. If you don't notice any improvement by 3 weeks, talk to your doctor. He or she may increase the dosage, switch to another SSRI, or use another medicine—clomipramine—if the medicine first prescribed doesn't help. Clomipramine has been used for years to treat OCD. But it may have more side effects than SSRIs.

Your doctor may prescribe other medicines if you have other conditions along with OCD.

Ongoing treatment

Ongoing treatment for OCD includes watching the dosage of your medicines and how well they are working. Your doctor may want you to stay on one medicine for at least 10 to 12 weeks before you try a different one. Antidepressants are thought to be the medicine that works best for OCD. But researchers are studying whether other medicines can be combined with antidepressants for better results.

If you are in counselling, your doctor will watch your progress. If needed, he or she may change the amount or type of counselling you get. You may need 13 to 20 sessions to relieve symptoms. Your doctor may also advise family members to take part in therapy with you or on their own.

Treatment if OCD gets worse

In rare cases of OCD when other treatment hasn't helped, deep brain stimulation may be tried. This involves magnetic stimulation of parts of the brain through surgically implanted electrodes.

What to think about

Consistency is important for both counselling and medicines. People who don't take their medicines on schedule or who stop taking them often have their symptoms return (relapse). With therapy, it's important to work with your doctor to find out when, or if, you should stop.

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It's important to take care of yourself every day when you have OCD. Do the homework your therapist gives you. And take your medicines as directed. The homework may include exercises called ERP. This stands for exposure and response prevention.

Reducing overall stress in your life is not a proven treatment for OCD symptoms. But it may help you cope.

It's a good idea to involve family members and loved ones in your treatment. This is even more important if your doctor suggested that you have therapy together. Keep the lines of communication open. It may help you deal with relationships that have become strained during your condition.

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Helping Someone Who Has OCD

In order to help someone with OCD, it is important that family members or loved ones learn as much as possible about the condition.

It may help to attend counselling or support groups with or apart from your loved one who has OCD. You can learn ways to help the person with behavioural therapy. And you can learn ways to help them take medicines regularly.

You may also help by providing the health professional with information on behaviours and the effects of treatment.

How you respond to your loved one's symptoms is important. An angry response can make the symptoms worse. And accommodating the behaviours may also be harmful. It is important that you talk to your loved one's health professional about how you should respond and the best ways for you to help.


Current as of: June 25, 2023

Author: Healthwise Staff
Clinical Review Board
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