What are intrusive thoughts?

Many thousands of thoughts pass through our minds every day. Some might come to mind for no apparent reason, whilst others may be triggered by for example a sensory stimulus such as a sight, sound, smell or taste, or a person, place, thing, or situation. These fleeting thoughts often disappear as quickly as they came to mind. They are something that everyone experiences and are normal, and usually random, such as in the middle of a meeting you might suddenly think “I must pick up some milk on the way home.”

More intrusive thoughts can also be a normal thing that many people experience from time to time. Research has shown that 94% of people experience unwanted, intrusive thoughts, images and / or impulses. Intrusive thoughts can happen to anyone and are sudden, involuntary, and often alarming, disturbing, or odd ideas, thoughts or images that enter the mind unexpectedly, without warning.

For most people, these intrusive thoughts are fleeting and can be easily dismissed or ignored, however for others they may be more frequent, intense, or cause them significant distress. In this article we will explore what is meant by intrusive thoughts, their causes and look at some of the treatments and methods to help you to deal with them if they are causing difficulties in your life.

What are considered intrusive thoughts?

An intrusive thought is an unexpected, unwanted thought, image, or idea that makes the thinker feel uncomfortable, that can range from mild unease to significant anxiety or even fear. These thoughts often feel out of character, may go against the thinker’s morals and values, are usually negative and can be irrational or weird.

Whilst there has been limited research into the phenomenon of intrusive thoughts, in his book “Intrusive Thoughts in Clinical Disorders: Theory, Research, and Treatment”, Dr David Clark defines intrusive thoughts as “distinct thoughts, images, or impulses that enter conscious awareness on a recurrent basis, are difficult to control, and interfere with ongoing cognitive and behavioural activity.” Meaning that these are thoughts you don’t want, and you can’t control, and they keep coming back into your mind.

So what makes a thought intrusive rather than just fleeting and random? These intrusive thoughts are usually completely alien to our usual thought patterns, possibly also prompting us to think “why on earth did I think of that?” Our minds generate random, spontaneous ideas or images, and these thoughts do not necessarily have a deeper meaning or desire, they are often just down to how the brain works, and for many people may be triggered at times of stress.

They may be linked to how our brains have a negativity bias, favour negative thinking, and are wired to focus on potential threats or dangers, even if these potential threats or dangers are unrealistic or irrational. Some researchers believe intrusive thoughts are a type of misinterpreted warning signal and may serve to protect us from our deepest fears or potential dangers. For example, thinking about stepping off a train station platform on to the track may prompt us to step back from the edge, away from danger.

Many people worry that they will act on their intrusive thoughts however studies have shown that people who have intrusive thoughts are not more likely to act on them. For most, the thought flits through their mind, unlikely to cause too much distress. However, for some people these intrusive thoughts linger and can become debilitating, often because the person finds their intrusive thoughts distasteful or conflicting with their values and beliefs

There are several common themes of unwanted intrusive thoughts, these include but are not limited to:

• Violence, aggression, and hurting self and / or others
• Sex and sexuality
• Contamination, germs and illness
• Relationship doubts or fears
• Bad things happening to yourself or others
• Self-doubt or doubt about whether something was done correctly
• Acting impulsively
• Doing something wrong, illegal or immoral
• Doing something that goes against your religion or belief system
• False memories

What are examples of intrusive thoughts?

There are many types of intrusive thoughts, and sometimes the theme of the intrusive thought fixates on something that is happening or is very important in that person’s life, let’s look at some examples in more detail.

A new parent may have intrusive thoughts, and research has found that around 50% of new mothers have had them, reporting that they are a common symptom of postpartum depression and anxiety. These intrusive thoughts may include harming their baby or just walking off and abandoning the baby. Other intrusive thoughts might include but are not limited to:

• Drowning the baby in the bath
• Shaking the baby
• Smothering the baby, for example, with a baby’s pillow
• Hitting the baby too hard during winding
• Throwing the baby to the ground or against a wall
• Releasing the baby in a pram from the top of a hill or into oncoming traffic

These intrusive thoughts are totally out of character and can be very stressful, leaving the mother feeling horrified that they could have thought anything so alien and abhorrent.

New fathers can also experience these intrusive thoughts, and they can manifest through engaging in compulsive behaviours such as constantly checking that their baby is safe because they are thinking that the baby has stopped breathing when they are asleep, or thinking that they may be interfering sexually with the baby when bathing or changing them so they avoid these activities.

The experience of these intrusive thoughts can be extremely upsetting particularly at what should be a happy time. However, new parents should remember that the fact that they are appalled by these intrusive thoughts is exactly what marks them as what they are, intrusive thoughts, and not actual desires. They should talk to their health professional about them, they will not be judged as bad parents or risk their child being taken away from them as these intrusive thoughts are perfectly natural at such a stressful time.

Intrusive thoughts can often happen in relationships, and can involve such things as self-doubt, for example, “Why am I getting ready for this date, they won’t turn up?” or “I am going to get dumped tonight”. Even in established relationships intrusive thoughts can occur, such as fearing something catastrophic has happened if your partner is late home, imagining them in a crashed car, or perhaps in the arms of another, even if you love and trust your partner completely.

Sometimes thoughts of harming them in some way may creep into your mind, or thoughts of being attracted to members of their family flash through your mind. It is not uncommon to occasionally have an intrusive thought at any stage of a relationship, often reflecting your greatest fears or most unwanted scenarios.

Doubts or self-doubt are some of the most common types of intrusive thoughts and can be about any aspect of a person’s life such as:

“Did I turn the cooker off?”

“Did I lock the car / house front door?”

“Should I have sent that text/email?”

“The milk was past its use by date, I shouldn’t have used it, I’m going to get sick”

“I’m going to say or do something stupid at the interview”

“My manager wants to talk to me, I’m going to lose my job”

In a study by Purdon and Clark (1993) 293 individuals who did not have a mental health problem were asked for examples of the intrusive thoughts that they had experienced, the 50 most common were:

1. Driving into a window

2. Running a car off the road

3. Hitting animals or people with a car

4. Swerving into traffic

5. Smashing into objects

6. Slitting wrist/throat

7. Cutting off finger

8. Jumping off a high place

9. Fatally pushing a stranger

10. Fatally pushing a friend

11. Jumping in front of a car/train

12. Pushing stranger in front of a car/train

13. Pushing family in front of a car/train

14. Hurting strangers

15. Insulting strangers

16. Bumping into people

17. Insulting authority figure

18. Insulting family

19. Hurting family

20. Choking family member

21. Stabbing family member

22. Accidentally leaving the heat/stove on

23. Home left unlocked, intruder there

24. Taps left on, home flooded

25. Swearing in public

26. Breaking wind in public

27. Throwing something

28. Causing a public scene

29. Scratching car paint

30. Breaking a window

31. Wrecking something

32. Shoplifting

33. Grabbing money

34. Holding up a bank

35. Sex with an unacceptable person

36. Sex with authority figure

37. Fly/blouse undone

38. Kissing authority figure

39. Exposing myself

40. Acts against sexual preference

41. Authority figures naked

42. Strangers naked

43. Sex in public

44. Disgusting sex act

45. Catching a sexually transmitted disease

46. Contamination from doors

47. Contamination from phones

48. Getting fatal disease from strangers

49. Giving fatal disease to strangers

50. Giving everything away

The content of these examples is commonly violent, sexually explicit, otherwise socially inappropriate or just out of character or potentially embarrassing. Be assured that intrusive thoughts are a normal part of the human experience and are usually harmless, despite their unsettling nature.

Are intrusive thoughts associated with any mental health conditions?

As we have previously stated, for many people intrusive thoughts are perfectly natural, fleeting notions that usually pass out of the mind as quickly as they enter it. When intrusive thoughts are a common occurrence that disrupts a person’s daily life, for some people these intrusive thoughts can be a symptom of many different mental health conditions such as:

• Anxiety disorders – a common symptom of generalised anxiety disorder (GAD), intrusive thoughts can cause persistent worry and anxiety about various things, and intrusive thoughts are often reinforced by getting entangled with them, worrying about them, struggling against them, or trying to reason them away.
• Obsessive-compulsive disorder (OCD) – intrusive thoughts can become persistent, obsessional, distressing, and often lead to compulsive behaviours for people diagnosed with OCD. Often trying to get rid of intrusive thoughts can become compulsions in themselves. Compulsions are repetitive things that people feel that they need to do to reduce the distress or uncertainty caused by their intrusive thoughts.
• Depression – this is a mood disorder characterised by persistent sadness, negativity and loss of interest in everyday activities. When someone is experiencing depression their mind is preoccupied with negativity, self-criticism, and hopelessness, and any intrusive thoughts can become more believable and intense. Someone with depression can feel that these are an accurate reflection of reality rather than merely intrusive thoughts.
• Postpartum depression or anxiety – Experiencing intrusive thoughts after having a baby is very common, but sometimes it is a sign of postpartum depression, anxiety or perinatal obsessive-compulsive disorder. Postpartum intrusive thoughts can manifest in a few different ways and leave parents feeling stressed, ashamed, or even frightened.
• Post-traumatic stress disorder (PTSD) – people diagnosed with this condition may experience intrusive thoughts and memories related to a traumatic event, they are often accompanied by flashbacks, nightmares, and heightened anxiety.
• Schizophrenia – intrusive thoughts alone are certainly not enough to indicate a possible schizophrenia diagnosis however as 12 to 23 percent of people with schizophrenia also have OCD, this may account for a person with schizophrenia experiencing intrusive thoughts.
• Eating disorders – anorexia nervosa and bulimia nervosa can also co-occur with OCD causing some people with these conditions to experience intrusive thoughts which can be about food, weight, body image, contamination, self-harm, or making mistakes. They may also engage in repetitive compulsive behaviours that are performed in response to intrusive thoughts and designed to reduce anxiety.
• Bipolar disorder – intrusive thinking is a fairly common but a rarely discussed symptom of bipolar disorder, however it is not one of its defining symptoms in the DSM-5. OCD and bipolar disorder share many symptoms and the statistics show that anywhere up to 20% of those living with bipolar show lifetime comorbidity with OCD, this may account for people diagnosed with bipolar experiencing intrusive thoughts.
• ADHD – obsessing and rumination are common characteristics of ADHD, where negative thought patterns continue in a cycle, so intrusive thoughts can be a feature of ADHD due to challenges in regulating attention and inhibiting thoughts.

What causes intrusive thoughts?

The exact cause of intrusive thoughts is not fully understood, however many experts believe that biological, psychological, or environmental stress is a major contributing factor to triggering intrusive thoughts.

As we have seen, intrusive thoughts can be more likely to occur in people who experience anxiety disorders such as those described above, however experiences of high levels of stress such as through illness, lack of sleep, or stressful situations can produce fight-or-flight responses which can cause the mind to generate unwanted or unsettling thoughts. This can be particularly noticeable at times of significant life changes or challenges such as getting married, becoming a parent, moving house, changing jobs, divorce, or the death of a loved one for example.

Lack of sleep and physical exhaustion can also play a role in the frequency and intensity of intrusive thoughts. When the body is tired, the brain may have difficulty processing emotions and managing stress effectively, leading to more unwanted mental intrusions.

Hormone imbalances may play a role in experiencing intrusive thoughts. Our hormones affect physical health, mood regulation, emotion, and overall mental health and any imbalance in hormone levels can lead to heightened levels of stress or lowered moods that might trigger intrusive thoughts.

Treatment for intrusive thoughts

For many people, they are able to successfully dismiss intrusive thoughts from their mind as fleeting notions, however for others these intrusive thoughts appear to take over their mind and can cause them distress. Although these intrusive thoughts can be debilitating, there are treatment options available to help them to regain control, manage their intrusive thoughts and to find relief.

Psychodynamic therapy is one treatment approach for intrusive thoughts that can help individuals to manage their intrusive thoughts. Psychodynamic therapy helps a person to understand how their current feelings and behaviours are shaped by their past experiences and their unconscious mind and impulses. It focuses on understanding the underlying psychological forces that shape a person’s emotions, thoughts, and relationships.

Cognitive behavioural therapy (CBT) can be a highly effective approach for managing intrusive thoughts. The aim of CBT isn’t to never have these intrusive thoughts, because intrusive thoughts cannot be avoided, but instead to help the person to identify, challenge and explore alternative meanings or beliefs about the intrusive thoughts.

Another form of therapy used in the treatment of intrusive thoughts is Exposure and Response Prevention (ERP). This is a specific type of cognitive behavioural therapy (CBT) used to treat anxiety and obsessive-compulsive disorder (OCD). The aim of the therapy is to reduce anxiety and teach individuals to cope with intrusive thoughts without resorting to compulsive actions.

In order to effectively treat intrusive thoughts, it is important to understand their underlying causes, as these may differ from individual to individual. It is recommended that a person experiencing intrusive thoughts that are causing them distress seek professional help in order to explore the causes and treatment options. If a person is experiencing intrusive thoughts frequently and it impacts their daily life, ignoring them and leaving them untreated can worsen a person’s mental health and overall well-being.

In some cases therapy may be used in conjunction with medication depending upon how much the intrusive thoughts are affecting the person’s life.

Medication for intrusive thoughts

Medications do not specifically target a person’s intrusive thoughts specifically. Rather they can help to reduce the overall symptoms of any associated mental health conditions including any intrusive thoughts. The main medications prescribed in the UK are a type of antidepressant called selective serotonin reuptake inhibitors (SSRIs). They work by increasing serotonin levels in the brain, which helps regulate mood, emotion, and sleep.

Serotonin is a neurotransmitter, i.e. a messenger chemical that carries signals between nerve cells in the brain. After carrying a message, serotonin is usually reabsorbed by the nerve cells known as reuptake. SSRIs work by blocking or inhibiting reuptake, meaning more serotonin is available to pass further messages between nearby nerve cells. A rise in serotonin levels can improve symptoms and make people more responsive to other types of treatment, such as CBT.

Clomipramine is a tricyclic antidepressant that can be used if SSRIs are not effective or not suitable for a person. Clomipramine also increases the amount of serotonin and norepinephrine in the brain and helps ease the symptoms of a number of different conditions including intrusive thoughts.

How to deal with intrusive thoughts

Intrusive thoughts as we have seen are a perfectly natural occurrence experienced by most people from time to time that they are able to let come and go from the mind. Others however may hold onto them or feel the urge to push them away. What is important is that you remember that they are just thoughts, and just a few of the thousands of other thoughts that pass through our minds every day.

Trying to stop or ignore intrusive thoughts can actually make them stronger, so don’t try to push the thoughts away, but label them as intrusive for example, if a thought such as “I’m going to mess up this interview” comes to mind, say to yourself “I am going to do the best that I can at this interview” and gently move your attention onto something else.

One way to deal with intrusive thoughts is to just let them pass through your mind without doing anything. Treat it as an object passing through your mind rather than something you need to engage with or act upon.

Redirect your mind to a more positive and productive focus such as engaging in an activity that captures your attention, such as reading, engaging in a hobby, or having a conversation with someone. By doing activities that fully engage your mind and body, you can create a healthy distraction, and your mind becomes immersed in the task at hand. This can help break the cycle of intrusive thoughts and provide temporary relief.

Physical movement such as going for a walk, doing yoga or just doing some housework, can also be effective in managing intrusive thoughts. Physical activity releases natural mood-boosting chemicals that can help reduce stress and the impact of intrusive thoughts.

Relaxation and stress-reducing techniques such as deep breathing, progressive muscle relaxation, and mindfulness meditation can help deal with intrusive thoughts as these can reduce their impact, aid improving sleep quality, reduce muscle tension, and promoting overall well-being.

Try not to attribute any meaning to unwanted intrusive thoughts, remember, you are not your thoughts and they are not an accurate reflection of who you are.

Speaking with a professional is a good step to get some extra long-term support for managing intrusive thoughts. Your GP can help to refer you, or you may prefer to contact NHS 111 who can also provide guidance and support by calling 111 or visiting their website.

Mind’s helplines provide information and support by phone 0300 102 1234 and email.

Information and support for people affected by OCD and intrusive thoughts can be gained through ocdaction.org.uk or ocduk.org.

Shout is the UK’s first and only free, confidential, 24/7 text messaging service for anyone who is struggling to cope. To start a conversation, text the word ‘Shout’ to 85258.

It can feel daunting to make the first move to talk to someone about your intrusive thoughts and how they make you feel, however letting someone know that you are struggling and taking that first step to talk with someone may help you to lessen the intensity of your experiences of intrusive thoughts.