Understanding OCD Symptoms: From Obsessions to Compulsions

Written by Danny Bonvissuto, Marijke Vroomen Durning, RN
Medically Reviewed by Poonam Sachdev on January 14, 2025
10 min read

Obsessive-compulsive disorder ( OCD) is a serious mental health disorder. Its name is often misused to describe people who like things super-clean or arranged just so. But when you actually have OCD, it affects more than just liking things done a certain way.

No one knows yet what causes OCD, but there are some theories. For example, you’re more likely to have obsessive-compulsive disorder if you have a biological parent or sibling who has it, so it might be genetic. Other possible causes include:

The “obsessive” part of the name obsessive-compulsive syndrome describes patterns of unwanted, uncontrolled thoughts or fears. Once those obsessions start, they lead you to repeat behaviors over and over again, until they become compulsions, the “compulsive” part of the name.

If you have OCD:

  • Your obsessions and/or compulsions take up more than an hour a day of your time.
  • You can't control them even when you're aware that they're unhealthy.
  • These thoughts and behaviors have a big impact on your life.

For many people with OCD, the symptoms follow a theme, and they don’t involve all aspects of life. 

Obsessions are when intrusive thoughts get stuck in your mind. These thoughts may upset you, and you may be afraid to tell anyone about them. 

OCD obsession themes

Themes for OCD obsessions could be related to:

  • Cleanliness, infections, illness, and dirt
  • Losing or misplacing things
  • Needing things to be orderly
  • Inability to control your actions
  • Hurting yourself or someone else
  • Believing in evil things related to sex or religion

Symptoms of OCD obsessions

Anyone can sometimes think obsessively or behave compulsively. OCD usually doesn't happen all at once, though, and neither do the symptoms. They start small. And to you, they can seem to be normal behaviors. They can be triggered by a personal crisis, abuse, or something that affects you deeply, like the death of a loved one. 

Symptoms of obsessions could be:

  • Feeling that everything has to be clean and free of dirt or contamination from germs
  • Always thinking you’ve forgotten to turn off the stove, lock the doors, or some other task
  • Needing things to be exactly in the right place in the right way, orderly
  • Having a hard time dealing with things that aren’t absolute, aren’t certain
  • Feelings that things are absolutely right or wrong, with no in-between
  • Fear of making mistakes, having to be perfect
  • Constantly needing to be reassured
  • Feeling aggressive or having bad thoughts, including losing control and causing self-harm or harm to others
  • Unwanted sexual or religious thoughts

Other symptoms include intrusive thoughts. These are unwanted thoughts that come into your mind, sometimes for no reason. An intrusive thought can take the form of:

  • A memory
  • An urge
  • A mental image
  • An emotion or sensation

We all have intrusive thoughts sometimes. Thinking something doesn't mean it's true or that you agree with it. For example, you might think about ramming your car into that of a driver who cuts you off in traffic. You'd never do something like that, so the thought may be upsetting. But if it’s a one-off thing, it’s likely not OCD.

When you have obsessive-compulsive disorder, an intrusive thought can turn into an obsession. You might develop compulsions to try to get rid of your intrusive thoughts.

Compulsions are things you do to try to ease the anxiety your obsessions cause. This never works for long. But you can't seem to stop doing them, even when they take up lots of time and interfere with your life. Compulsions can take several forms and follow themes, like obsessions.

OCD compulsion themes

The themes of the compulsions would be related to the obsession – following rituals, needing things to be clean and orderly, having to control yourself at all times, and ensuring that appliances are turned off and doors locked. 

Symptoms of OCD compulsions 

These symptoms would also relate to the obsession. You would feel the absolute need to do these compulsions, even if you don’t want to. If you try to not do the act, the urge to do it gets stronger and stronger until you can’t hold off any longer. So to keep that from happening, you may make rules that you need to follow, and when you follow them, you may feel relief – but it’s temporary.

You can't seem to stop doing them, even when they take up lots of time and interfere with your life. Compulsions can take several forms. 

Rituals. Obsessive-compulsive disorder rituals might include:

  • Saying things, out loud or to yourself, over and over
  • Washing your hands or taking showers repeatedly
  • Excessive cleaning
  • Arranging things in a particular way 
  • Touching items in a certain way or at a certain time

Rumination and correcting thoughts. Rumination might look like:

  • Going over the same thing in your mind over and over
  • Researching your obsession online
  • Trying to stop intrusive thoughts by thinking about what they mean

Correcting thoughts might take the form of:

  • Counting to a particular number
  • Saying something, in your head or out loud, over and over
  • Trying to replace an intrusive thought or feeling with a different one
  • Repeating an act until it feels right to you

Repetitive checking. You might repeatedly check:

  • Your body or clothes for dirt
  • Your door to make sure it's locked
  • The lights or appliances to make sure they're off 
  • Your phone to see if you texted or posted something offensive
  • The route you took home to make sure you didn't cause a wreck
  • Your memory to make sure something you thought about didn't actually happen

Looking for reassurance. With this kind of obsession, you could:

  • Apologize to someone over and over
  • Keep asking those around you whether everything is OK
  • Keep telling yourself your intrusive thoughts aren't real
  • Say or do things to see how others react
  • Ask others what your intrusive thoughts mean

Avoiding. This means avoiding things that make you feel anxious. You might:

  • Remove knives or other things from your home that could injure you or someone else
  • Put off doing things that make you feel uncomfortable (procrastinate) 
  • Stop doing things that trigger your anxiety, such as driving if you're afraid of an accident
  • Stay away from certain people

You might hear people talk about "types" of OCD, but doctors don't actually diagnose different types. Some obsessions and compulsions do follow particular themes or topics. Yours might center on one theme, or several. Below are several common themes, but many obsessions and compulsions don’t fall neatly into any of them. 

Contamination OCD symptoms

You might fear that you've been physically contaminated by dirt or germs. Or you might worry that you have or will get a contagious disease. You could worry that you'll spread this contamination, or that others are spreading it.

You could also feel like you're contaminated mentally. You might feel dirty, uncomfortable, or incomplete. Certain people, places, or things might trigger these feelings.

Relationship OCD symptoms

You may fear that people in your life may dislike you or plan to leave you, or worry about whether a relationship is working. You could have these feelings about anyone you come into contact with, from strangers to friends and family members.

These symptoms can also take the form of intrusive thoughts about sex. They might be inappropriate, such as about family members or children, or involve aggression. Having these thoughts doesn't mean you actually want to act on them. 

Identity-based OCD symptoms

You may worry that you are a bad person. You may obsess over whether you've said something wrong or keep thinking about past regrets. 

You could be hyper-aware of your body. You might be anxious about how you feel or look. Or you could think too much about sensations like swallowing or breathing.

Your obsessions could center on your sexuality or gender identity. You might also doubt your beliefs and value system.

Harm- or violence-related OCD symptoms

You could worry that you have hurt or killed someone, or that you will in the future. 

You might have intrusive thoughts about being abusive or violent to others. 

Pure O

This phrase means purely obsessional. In other words, you have obsessions but no compulsions that others can see. That doesn't mean you don't have compulsions. You just do them mentally or internally. You might:

  • Think about something over and over
  • Repeat numbers or words in your head
  • Keep checking your emotions or body sensations
  • Check again and again how a certain thought makes you feel
  • Keep assuring yourself that you're OK and your thoughts aren't real

Many people with OCD also have tics. This might not be surprising, given that there might be a connection between OCD and Tourette’s syndrome, a tic disorder. A tic disorder, like Tourette’s, is a neurological condition that causes you to have tics. These  are sounds (vocal) or movements, like clearing your throat or blinking your eyes, that you repeat over and over again. You can't stop yourself from doing them. 

When someone is diagnosed with a tic disorder, their doctor will likely want them checked for other connected conditions, like OCD.

Women and those who were assigned female at birth (AFAB), and men and those who were assigned male at birth (AMAB) can have different OCD symptoms. According to some research, men and those who are AMAB may be more likely to have:

  • Social phobias
  • Tic disorders
  • Alcohol use disorders
  • Compulsive internet use
  • Sexual disorders

Women and those who are AFAB have higher rates of:

  • Eating disorders
  • Specific phobias
  • Trichotillomania (pulling out hair)
  • Skin picking
  • Compulsive buying

OCD symptoms can start at any age, but for most people, they begin in late childhood or early adulthood. 

The symptoms and themes of OCD in children are much the same as in adults, but they may change according to age, grade, and stage of childhood. Since it’s possible that OCD could be related to having had a strep infection, if you notice any changes in your child after an illness like strep throat, mention this to your doctor.

OCD symptoms may clear up from time to time or get steadily worse, and they're often worst when you're stressed. Your particular obsessions and compulsions can change as time goes on. 

If you think you might have obsessive-compulsive disorder, see your doctor or a mental health professional, like a psychiatrist, psychologist, or clinical social worker.

There's no single test that can detect OCD. Your provider will ask you about your health history and symptoms. The diagnosis process will likely also include:

  • A physical exam to see if your symptoms are due to a health condition
  • Blood tests to check your blood count, how well your thyroid works, and any drugs or alcohol in your system
  • A psychological test or evaluation of your feelings, fears, obsessions, compulsions, and actions

To be diagnosed with OCD, you must have obsessions, compulsions, or both. They must:

  • Cause you distress or anxiety or interfere with your work, social life, or other parts of your life
  • Take up more than an hour of your time each day
  • Not be explained by other mental health conditions you may have, like an anxiety disorder or an eating disorder
  • Not be caused by a health condition, substance abuse, or medications you take

With obsessive-compulsive disorder, you have repeated unwanted thoughts (obsessions) and/or perform repetitive actions or rituals (compulsions) that you feel you can't control. They cause you distress, and interfere with your time and your life. If you think you may have symptoms of OCD, see a doctor or mental health provider.

When do OCD symptoms start?

Obsessive-compulsive disorder symptoms can begin at any age. But in about half of people with OCD, they start during late childhood or early adulthood. The average age at diagnosis is 19. Only rarely do OCD symptoms start after age 40.

How do I check if I have OCD?

You can check if you have OCD by reviewing the symptoms to see if any of them match what you’re feeling or doing. Everyone can be compulsive or obsessive about something from time to time, so the difference is if your obsession or compulsion is having a negative effect on your life.

What causes obsessive thinking?

No one knows for sure what causes obsessive thinking. Some people believe that it’s genetic (runs in families) or that it might be caused by a trauma. There are other possible causes, like changes in the brain.

What are high-functioning OCD symptoms?

OCD symptoms aren’t classified as high-functioning or low-functioning.

What triggers OCD?

It’s not known what triggers OCD, but it could be related to brain changes, genetics, or even trauma as a child.

How does OCD affect daily life?

Obsessive-compulsive disorder can affect your daily life in many ways. Your obsessions and compulsions can:

  • Take up a big part of your day
  • Interfere with family and social life
  • Get in the way of your education and career

Can someone with OCD fall in love?

Obsessive-compulsive disorder differs from person to person. People with OCD can fall in love and have happy, committed relationships. Sometimes, entering such a relationship can set off anxiety and trigger OCD symptoms. But with communication, support, and the right treatment, these challenges can be overcome.

How can you tell if someone has OCD?

People with OCD have obsessions, compulsions, or both. These obsessions and compulsions:

  • Cause them anxiety or distress
  • Get in the way of their work, social life, and family relationships
  • Take up more than an hour per day of their time
  • Aren't explained by other physical or mental health conditions, medications, or substance use

What does undiagnosed OCD look like?

Someone with undiagnosed OCD might have severe OCD symptoms that affect their quality of life.