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Intrusive thoughts, what are they and why you get them.

What are intrusive thoughts?

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

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

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Are intrusive thoughts normal?

Having intrusive thoughts is perfectly normal. 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 can 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.

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

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?

Postpartum depression

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

Post-traumatic stress disorder

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. (2010 3) the thoughts fall under several categories.

  • Contamination
  • symmetry/ incompleteness
  • responsibility for harm, and
  • intrusive taboo thoughts.

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 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.

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.

  • Religious
  • Violent
  • Sexual; this includes your sexual identity and inappropriate sexualised thoughts.

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 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.

It can comprise an impulse to be aggressive to someone or cause 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 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 your 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 worrying 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

Worrying about your kids and family when they are not with you is normal. Still, you might 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 message when they are leaving to come home.

Do I Need To See A Doctor?

Meeting with your doctor or a licensed mental health professional is advisable 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 according to DSM, obsessions are 

Recurrent and persistent thoughts, urge, 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 other thoughts or actions.
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 eliminate 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, 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 become an obsession.

Are Intrusive Thoughts Normal?

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 a distressing one 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.

Why Are The Thoughts About Bad Things?

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 like 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 differs 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 it, and 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 you get, tend to go after your value base – the things you would never do.
Urges can also include the desire to carry out a compulsion, e.g., if you think that you could hurt someone else, you might be urged 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. A good understanding of what is happening puts you in control and ready to take steps to overcome intrusive thought. 

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

Further reading

10 Sources

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. 

Cambridge Dictionary
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.
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. 10.1037/a0018260. PMID: 20230164.
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.
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.
International Statistical Classification of Diseases and Related Health Problems (11th ed,; ICD-11; World Health Organization, 2019).
Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013).
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.
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.
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.