Intrusive thoughts, what they are and how to stop them.

Dr Elaine Ryan
Written by Dr Elaine Ryan Psychologist and Founder of MoodSmith® Elaine obtained her Dr in Psychology from the University of Surrey and has worked in psychology for 20 years. Dr Ryan specialises in Intrusive Thoughts, OCD and anxiety-related conditions.

What are intrusive thoughts?

If you have had the thought, what if I jump in front of the train while waiting on the platform, you have had an intrusive thought. One of my own random thoughts was poking myself in my eye with the toothbrush while brushing my teeth.

The word intrusive according to the Cambridge Dictionary 1 means affecting someone in a way that annoys them or makes them feel uncomfortable, and as such, positive thoughts that pop into your mind uninvited cannot be termed intrusive.

Are intrusive thoughts normal?

Having intrusive thoughts is a perfectly normal phenomenon. Almost everyone gets them, 94% of the population according to Professor Radomsky 2 , experience uninvited thoughts. Most people can ignore them, but for others, these intruders of the mind can impact a person’s life due to mental health conditions or when going through difficult stages of life such as illness, grief or periods of prolonged stress.

For example, a cancer patient, given the all-clear after lengthy chemotherapy, may experience unwelcome thoughts that their cancer may reoccur or a person seeking employment, following many rejection letters could have intrusive thoughts that affect their self-esteem and motivation to look for work. Experiencing these types of negative thought patterns does not mean that you will end up having intrusive thoughts in the clinical sense, that are part of mental health conditions.

If intrusive thoughts are normal how will I know when they are a mental health condition?

If you are able to dismiss the thought and it does not interfere with your daily life, you do not have a problem.

If the thought keeps repeating and causes distress, this is more obsessional in nature.

Furthermore, if you start doing things to ease the discomfort, such as checking or seeking reassurance, these actions that you feel compelled to do, are the start of compulsions. Not being able to ignore the thought and behavioural changes are signs that they may be affecting your mental health.

It is helpful to read this article on what thoughts are.

What mental health conditions have intrusive thoughts?

People with OCD experience intrusive thinking when they are thinking, for example. Did I lock the door? Have I done something terrible in the past?


You may experience postpartum OCD with anxiety-related thoughts that make you think you could harm your baby, which causes intense distress.

The mental flashbacks associated with post-traumatic stress are one of the significant symptoms of PTSD.

The remainder of this article shall discuss the intrusive thoughts that occur as part of obsessive compulsive disorder.

Most people are aware that OCD consists of obsessions and compulsions, but the content of the obsessions varies. According to Abramowitz et al. (20103the thoughts fall under several categories.

The public perception of OCD and most research covers contamination, symmetry, and responsibility for harm, with less understanding or awareness of intrusive thoughts. This lack of attention may be due to a sense of shame or stigma surrounding more taboo content (Glazier et al., 2015).4 According to Cathey & Wetterneck, (2013) 5, the public finds more taboo thoughts socially unacceptable. This stigma may render the person with intrusive thoughts less likely to seek treatment or disclose their suffering.

Table of Contents

Definition of intrusive thoughts

Intrusive Thoughts refer to unintentional and distressing thoughts, impulses or images that are both difficult to control and unwanted. They are disruptive to the person in that they can interrupt what the person is doing and their flow of thought.

The content of intrusive thoughts can fall into to following themes.

Examples of intrusive thoughts

Sexualised thoughts

These can include thoughts or mental images of violent sexual acts, sex with inappropriate people or things, questioning your own sexual identity or any sexual idea that cause you distress.

These types of thoughts can be distressing, as arousal is involved. Even though you have not carried out the act, the idea of it may cause you to feel aroused.

Arousal does not mean that it is true; it is a normal physiological response.

Unwanted thoughts regarding children

These intrusive thoughts or mental images are distressing, as you may have unwanted thoughts that could harm a child somehow. This can include unwanted thoughts that you could cause harm to your child.

These types of thoughts can occur in postpartum depression and are part of mental illness instead of reflecting on you as a person.

Read more on Postpartum OCD and also POCD.

Aggressive thoughts

These may involve causing harm to yourself or others. Again, these thoughts are distressing as they may include the fear that you may hurt someone, even though you have probably never hurt someone in your life.

It can comprise an impulse to be aggressive to someone or causing physical harm. This does not mean you will carry this out, instead see it as one symptom of OCD.


These include inappropriate sexual thoughts regarding religious people or figures. Swearing during prayer or worship. Strong urges to misbehave during services.

Most people that I work with find it difficult to see these as harmless thoughts. They are more than likely to see them sign that something must be wrong with them to have such ideas.

Or even believe the thoughts–“Why would I be having them if I haven’t done……..?” They are just thoughts.

Read more on Religious OCD

Sexual identity

Many people have unwanted intrusive thoughts that make them question their sexual orientation. This is not the same as someone who knows that they are attracted to the same sex. Suppose you have intrusive thoughts regarding your sexual orientation. In that case, you still are heterosexual, but you may suffer from doubts because of the beliefs. It is known as Homosexual OCD, and I have a detailed post on HOCD here.


These can include thoughts relating to;

  • Kissing members of your own family.
  • Sexualised thoughts regarding family members.
  • Intrusive images of family members, for example, naked.
  • “What if I am attracted to my sister, my brother?” etc.


This can include being worried about death, which your heart could give up. It can also include distressing images of death, either you own or someone you care about.

Needing certainty

It is normal to worry about your kids and family when they are not with you. Still, you might find that you worry and experience intrusive thoughts and images concerning their safety. These can include.

Thinking that they have had an accident when you have no real reason to believe this.

Thinking that they could come to harm or hurt themselves.

These types of thoughts may make you seek reassurance regarding their safety. You might tell people you care about sending a message or calling you when they reach their destination or to message when they are leaving to come home.

Do I Need To See A Doctor?

It is advisable to meet with your doctor or a licensed mental health professional to get a correct diagnosis. Getting a diagnosis and understanding why the thoughts occur can be the basis of a treatment plan. 

How Are They Diagnosed?

Suppose you meet with a mental health professional. In that case, they will undertake a complete assessment of your presenting problem to provide you with a diagnosis. This diagnosis is to formulate a plan of treatment. 

The psychologist or physiatrist will ask you a series of questions to determine, for example, if your unwanted thoughts are occurring because of a specific mental health condition, such as OCD.

There are two main manuals that a clinician may refer to for diagnostic criteria:

  • International Classification of Diseases; ICD1.1  6
  • Diagnostic and Statistical Manual of Mental Disorders; DSM2.  7

In my career, I would have referred to the DSM and is according to DSM, obsessions are 

  • Recurrent and persistent thoughts, urges, or images experienced during the disturbance as intrusive and inappropriate and cause marked anxiety and distress.
  • The person attempts to suppress or ignore such thoughts, impulses, or images or neutralise them with some other thought or action.

If, for example, your diagnosis is that your intrusive thoughts are occurring because of having Obsessive-Compulsive Disorder, your clinician can then devise treatment based on the diagnosis of OCD.

Will they ever go away?

To answer this, it is worth talking about intrusive thoughts and obsessions. The goal is not to get rid of unwelcome thoughts as this is impossible. Everyone gets intrusive thoughts, but as noted by Rachman, (1997)  8 people with OCD place too much importance on these types of thoughts, and the distress then experienced compels the person to perform compulsions to ease their pain.

What is causing you pain is not the intrusive thoughts per se but how much power the idea has over you. Do you believe it? Do you feel personally responsible for having thoughts like this? Do they interrupt your day or result in you spending time performing mental analysis or avoiding certain aspects of your life as you are afraid of being triggered?

So, to answer, do intrusive thoughts ever go away, in terms of OCD, the obsessions and compulsions, with proper treatment? Yes, they can. Will you ever get an intrusive thought again? Yes, you will, just as I will, but it does not have to turn into an obsession.

stop intrusive thoughts image shows Moodsmith therapy session

How to stop intrusive thoughts

In this section I shall discuss things that you can try by yourself to help with your thoughts before explaining more formal therapy options.

It follows a stepped care approach to treatment where you start with the least intensive intervention such as self-help before moving up to counselling with a licensed mental health professional.


If you analyse your thoughts, wondering why you have them or what it says about you as a person, there are models of therapy that will help you stop doing this.

Why do you need to stop doing this?

Thoughts need the energy to survive. Acceptance and Commitment Therapy works well as it teaches you to label the thought and move on.

You can do this right now, although it takes practice. Next time you have an intrusive thought, label it just as a thought and move your attention away rather than dedicate time to it. Try it now.

Decide on your label. You can use a label such as.

there’s an intrusive thought
it’s just a thought

Don’t push the thought away; this does not work. The more you tell yourself to stop thinking about something, the more likely you will think about it. Try this for yourself. Don’t think about your favourite food for one minute. This might be desserts, pie, steak, whatever it is, do not think about it.

Did you notice an increase in saliva? If you did, not only did you think about the thought, but you changed your physiology, as your body is now preparing for food!

Keep labelling; there’s a thought, and move on.

At the moment, if you are suffering, you cannot accept intrusive thoughts as ‘just a thought.’ You react to them as accurate or worried that you might act on the thoughts and cause some harm either to yourself or someone else. You have developed several ways to cope with your thoughts, including avoiding things or avoiding your thoughts.

Learning to accept your thoughts helps to stop the thought-action fusion. This is where you believe that thinking about something makes it more likely to happen.

Once you have been taught to accept them, the thoughts shall no longer mean anything to you with practice. They keep popping into your mind at the moment because you shine a spotlight on them, trying to figure out what they mean, trying to avoid them, and adopting various tactics to make sure you do not harm. Your brain has decided, ‘this is something we need to pay serious attention to.’ Learning to label them and move on helps to stop this.

You might have changed the way you exist in the world to prevent you from causing some harm (concerning your thoughts.) For example,

  • If you have intrusive thoughts regarding knives, you might have moved the blades in your kitchen, or
  • If you experience intrusive thoughts regarding children, you might avoid children’s parties, be extra careful with how you look at a child or be uncomfortable bathing and dressing children. or
  • If you have unwanted thoughts regarding your sexuality, you may avoid people, places or things that trigger your thoughts.

It would be best if you learned to stop doing this, as even though the strategies you have developed help you in the short term, they are not effective long term, as they only keep this cycle going.

Cognitive Behavioural Therapy, in addition to mindfulness-based approaches, combined with relaxation training, will help you achieve this.

There is a stark contrast between I will stand up and shout something obscene in Church right now, and I am worried I might say something blasphemous. 

 The first thought contains action, something you will do now, whereas the second thought is a worry, a doubt. Reality-based action thought. I am going to punch that person. Doubt, I am worried I might hurt someone.

Understanding the difference between doubt and reality is crucial in overcoming unwanted intrusive thoughts. Once you can see the difference, it becomes easier to accept that you need to work with doubt instead of the content of the thought.

Being worried that you might do something or have done something in the past and cannot remember it is not the same as actually doing it.

People with intrusive thoughts go out of their way, carrying out elaborate compulsions to ensure that they never act on the thought.

For example

People with obsessive thoughts or Pure O may not be aware that they carry out compulsions. The following examples will highlight some of the compulsions you may do and need to work on to end intrusive thoughts. 

People with HOCD may check themselves to ensure their sexual preference has not changed. This checking is carried out to ease the distress caused by internal thought and is a compulsion.

Someone with Harm OCD may remove objects they fear might hurt someone. This compulsive act is carried out to prevent a feared consequence.

I shall start with a more classic OCD example to explain how to start trusting your judgment.

A person with OCD may lock their front door, repeatedly pull the handle, unlock and relock and stare at the door for a long time before feeling able to walk away.

The doubt that characterizes OCD makes locking up very difficult for the person; they cannot trust their actions and sight.

In non-OCD tasks, they rely on their senses; for example, if a person has just put a plate in the cupboard and walked away and I ask where is the plate, they will answer in the closet as they can trust their actions and their sight that they saw the plate in the cupboard.

If I ask two people about their romantic preference, one may state; that they are, for example, heterosexual, and if I inquire how they know, they can trust their judgment to answer the question.

However, if the person has Sexual orientation themed OCD, they will not be able to trust their decision as they are plagued with doubt caused by OCD.

The person with HOCD may no longer trust their judgement and check to see if they are attracted to members of the same sex or opposite sex if they are lesbian or gay.

If you have been heterosexual or in a same-sex relationship, your sexual identity should be a given; it is a fact based on reality.

The doubt caused by intrusive thoughts conflicts with reality.

Do not overuse your senses.

In the example above, where the person repeatedly locks the door and stares at it, to overcome the obsessive thought that the door might not be locked they have to relearn to trust their senses, and they do that by using the following.

Lock the door and look at the action of turning the key and walk away. It can be challenging to begin with, as doubt will create high anxiety levels.

Resist walking back to check the door, as this will reinforce the pattern that checking makes you feel more relaxed and reassured.


Online self-help

If you would like my help, please see my online course.

Therapy for intrusive thoughts

Psychoeducation. Arm yourself with information
If you are ready to start therapy, I appreciate that this may be a daunting prospect, as you may feel deep shame and fear regarding discussing your thoughts. For that reason, I have included articles on MoodSmith to make the process as transparent as possible.
Start by reading this introductory series.

Treatments that help

Cognitive behavioural therapy CBT

CBT is well researched and remains one of the most effective models of therapy9

 to help with the intrusive thoughts of OCD. Intrusive thoughts are maintained through a pattern of fear, avoidance and compulsions, and CBT addresses this pattern.

The person with intrusive thoughts is systematically encouraged to explore their thoughts instead of avoiding them. The tenet of CBT is to help the person change their thought processes and behaviours to ones that will break the cycle of OCD.

Read more on CBT here.

Exposure and Response Prevention ERP

Exposure and response prevention is a gold standard, according to Abramowitz, 199610

 in the model, you are exposed to your intrusive thoughts without ritualising. Ritualising is where you perform the compulsion, such as assurance seeking.

You can read more on ERP here and how it helps intrusive thoughts here.

FAQs intrusive thoughts

In a word, yes! Everyone gets intrusive thoughts; I get them. 

The only difference between an intrusive thought that pops into your head and then leaves, and an intrusive thought that is distressing, is how you respond to it.

If you react to the thoughts as if they were true and change your behaviour as you are concerned, you could carry out the thought; this is the beginning of obsessions and compulsion.  

The thought becomes obsessive and creates distress. The distress leads to a compulsion to help to make you feel better.

I think the best way for me to answer this is to do it in two parts;

  • what things are important to you, and
  • how much attention you pay to the thought.

Intrusive thoughts latch on to the things that are important to you. For example, I adore animals; if the idea popped into my head that I could harm an animal, this would certainly grab my attention, as it would shake my values to their core.

I could have several uninvited thoughts in my head, but most will go unnoticed. Those that go against my core values will stick out from the rest. 

If you get an unwanted thought that goes against your core values, you will probably feel something, such as fear, disgust or alarm. These strong negative emotions make the thought appear more robust than it is.

So to answer the first part of why the thoughts are about bad things, it is essential to note that it is different from person to person. It is what you consider bad; what would attack your core values. 

Once a thought strikes your core values, if you leave it alone, it will wither and die, but if you pay attention to it, think about it, analyse, give it special attention amongst all the other thoughts, it will become stronger.

The urges are the same as the thoughts; they are both a symptom in that they fall under the umbrella of obsessions. An urge is an obsession.

Typical urges experienced in OCD and Intrusive Thoughts

  • Touch someone inappropriately
  • Want to kiss someone? This can include kissing someone that would seem inappropriate, such as members of your own family, members of the same sex (if you are heterosexual)
  • to hurt someone that you care about
  • To confess to something that you haven’t done.
  • The urges you get depend on what you hold dear, what you value most. Intrusive Thoughts, including the urges that you get, tend to go after your value base – the things that you would never do.

Urges can also include the desire to carry out a compulsion, e.g. If you get the thought that you could hurt someone else, you might have the urge to remove all implements that could cause harm.

Or, if you falsely believe that you are a terrible person and have done something bad, you might have the urge to confess.

Are the urges different from the thoughts?

No, both the urges and the thoughts are, in fact, obsessions.


Any random thought can become intrusive, if it disturbs you or you change how you react based on the content of the thought. Having a good understanding of what is happening puts you in control and ready to take steps to overcome the intrusive thought. 

Should you wish to continue reading my articles, you can find more on the subject here.

Further reading

All content on MoodSmith is written and researched by Dr Elaine Ryan and uses only peer-reviewed research on journals, government bodies, universities and professional bodies to support the article. 


  1. Cambridge Dictionary
  2. Radomsky, Adam & Alcolado, Gillian & Abramowitz, Jonathan & Alonso, Pino & Belloch, Amparo & Bouvard, Martine & Clark, David & Coles, Meredith & Doron, Guy & Fernández-Alvarez, Héctor & Garcia-Soriano, Gemma & Ghisi, Marta & Gómez, Beatriz & Inozu, Mujgan & Moulding, Richard & Shams, Giti & Sica, Claudio & Simos, Gregoris & Wong, Wing. (2013). Part 1—You can run but you can’t hide: Intrusive thoughts on six continents. Journal of Obsessive-Compulsive and Related Disorders. 3. 10.1016/j.jocrd.2013.09.002.
  3. Abramowitz JS, Deacon BJ, Olatunji BO, Wheaton MG, Berman NC, Losardo D, Timpano KR, McGrath PB, Riemann BC, Adams T, Björgvinsson T, Storch EA, Hale LR. Assessment of obsessive-compulsive symptom dimensions: development and evaluation of the Dimensional Obsessive-Compulsive Scale. Psychol Assess. 2010 Mar;22(1):180-98. https://doi: 10.1037/a0018260. PMID: 20230164.
  4. Glazier, Kimberly & Wetterneck, Chad & Singh, Sonia & Williams, Monnica. (2015). Stigma and Shame as Barriers to Treatment in Obsessive-Compulsive and Related Disorders. Journal of Depression and Anxiety. 4. 191. 10.4191/2167-1044.1000191.
  5. Cathey, A. J., & Wetterneck, C. T. (2013). Stigma and disclosure of intrusive thoughts about sexual themes. Journal of Obsessive-Compulsive and Related Disorders, 2(4), 439–443.
  6. International Statistical Classification of Diseases and Related Health Problems (11th ed,; ICD-11; World Health Organization, 2019).
  7. Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013).
  8. Rachman S. A cognitive theory of obsessions. Behav Res Ther. 1997 Sep;35(9):793-802. doi: 10.1016/s0005-7967(97)00040-5. PMID: 9299799.
  9. McKay D, Sookman D, Neziroglu F, Wilhelm S, Stein DJ, Kyrios M, Matthews K, Veale D. Efficacy of cognitive-behavioral therapy for obsessive-compulsive disorder. Psychiatry Res. 2015 Feb 28;225(3):236-46. doi: 10.1016/j.psychres.2014.11.058. Epub 2014 Dec 8. PMID: 25613661.
  10. Abramowitz, J. S. (1996). Variants of exposure and response prevention in the treatment of obsessive-compulsive disorder: A meta-analysis. Behavior Therapy, 27(4), 583–600.


If you would like my help, please see my online courses.

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