Overview

Nightmares refer to disturbing or unsettling dreams that awaken you from your sleep and are associated with negative feelings, such as anxiety, fear and panic. While experiencing the occasional nightmare is thought to be common, the nightmares associated with nightmare disorder are distinct in terms of their increased frequency and impact on the individual’s emotional health.

Nightmare disorder is a relatively rare type of parasomnia (i.e., sleep-related disorder).¹ The term is used when people experience recurrent, frequent and extended nightmares in which they feel a threat to their safety, wellbeing and life, or to that of those they care about. 

Most of these nightmares occur during the last, deepest stage of sleep known as rapid eye movement (REM) sleep.² Dreams can occur in other sleep stages, but it is solely within this REM stage that dreams are more vivid and longer in duration.

Such nightmares typically disrupt the sleep of people affected by abruptly waking them up into a vigilant and distressed state. In turn, this conditions a sense of fear in the individual when it comes to going to sleep and they exhibit a reluctance to sleep because they anticipate suffering nightmares. 

Individuals often experience loss of sleep resulting in impairments in daytime functioning, inability to maintain good sleep habits (sleep hygiene), poor sleep duration, and continuous distress. All this can contribute towards wider issues involving decreased physical and mental health.

Signs and symptoms of nightmare disorder

A fundamental symptom of nightmare disorder is experiencing nightmares that are disturbing and associated with negative, anxiety-provoking feelings that awake you from slumber. They occur during the latter stages of sleep when an individual is abruptly woken and in significant psychological distress from the unsettling experience.

Other characteristic symptoms include:

• A threat of danger that could be either physical or psychological is involved in the nightmares
• The person may groan and mumble – these are small behavioural responses in comparison to big responses such as the shouting or moving about associated with other parasomnias
• Remembering details of the dream and waking independently in a lucid and alert state

The difference between nightmare disorder and night terrors

Experiencing nightmares is a defining characteristic of nightmare disorder. On the other hand night terrors (or sleep terrors) refer to episodes of extreme panic and confusion that the person affected has difficulty waking from and there is usually no recollection of a nightmare. 

Unlike nightmare disorders, night terrors do not happen during REM sleep. Instead, they occur during the sleep stage of non-rapid eye movement (NREM) sleep – in its third, deepest part. Trying to help during a sleep terror episode should be avoided because this can frighten and confuse the sufferer even more and potentially lead to an aggressive reaction. Therefore, being able to differentiate nightmare disorder from night terrors is important.

This table outlines some of the main characteristics that distinguish nightmare disorder from night terrors.

However, nightmare disorder and night terrors are not mutually exclusive because individuals may suffer from both.³ 

Night-time effects of nightmare disorder

Specific night-time effects of nightmare disorder include:

• Fear of falling asleep (Somniphobia) – is a common consequence of nightmare disorder because people affected want to avoid experiencing the nightmares again 
• Sleep disorders, such as insomnia – difficulty falling and staying asleep can arise due to the fear associated with sleeping
• Compromised sleep – decreased duration of sleep and diminished quality of sleep
• Continuous disruption of sleep for caregivers and bedroom-sharers who are woken up to respond to the child’s nightmares⁸

Day-time effects of nightmare disorder

Specific day-time effects of nightmare disorders include:

• Fatigue and daytime sleepiness – contributing to an overall lack of energy and motivation to do things
• Persistent negative emotions and psychological distress (e.g., increased anxiety and fear) which impair wellbeing and can lead to mood disturbances (e.g., anxiety and depressive disorders)
• Cognitive issues (e.g., difficulty concentrating and fixation on the nightmares during the day leading to distraction from intrusive thoughts)
• Anticipatory anxiety – anticipatory fear about going to sleep at night 
• Impaired day-to-day functioning in various contexts (e.g., work, school, social or even with family)⁸

How is nightmare disorder diagnosed?

There is no set structure for obtaining a clinical diagnosis, however, consulting a medical healthcare professional or a sleep specialist can help.

Experiencing nightmares occasionally doesn’t necessarily mean you suffer from a nightmare disorder. Instead, a diagnosis is often given when these nightmares have been occurring for a long duration and are negatively affecting your ability to function in life. 

The latest text revision of the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR), published by the American Psychiatric Association (APA), is used by healthcare professionals to help with the assessment and diagnosis of nightmare disorder.

A medical health professional will assess the following before determining whether a diagnosis of nightmare disorder is applicable in your case:

• Individual symptoms
• Family history
• Medical background (including substance intake or withdrawal)
• Physical examination
• Nocturnal sleep study (polysomnography)²⁹

The main reason for all these examinations and inspections is to ensure that nightmare disorder is the actual reason for your difficulties. Importantly, it seeks to rule out the potential of other physiological and psychological conditions, as well as other sleep-related disorders, causing the nightmare episodes.

Causes of nightmare disorder

Much research suggests that nightmare disorder stems from two key underlying factors:

1. Increased hyperarousal

Elevated levels of arousal (i.e., hyperarousal), which include anxiety, build up during the day and continue into the night. As a mood-altering symptom, hyperarousal is likely to evoke overactivity in certain brain areas when asleep resulting in nightmares.¹² 

2. Impaired fear extinction

Fear-based memories are suppressed during the daytime; however, they are set off during the night when sleeping. Normally the memories become diluted and extinguished as we combine them with new and unrelated contexts thereby diminishing how they impact us. However, the inability to do this results in these memories maintaining their effect of instilling fear and individuals can continue activating and reinforcing these fearful and distressing memories during their sleep, thereby contributing to them experiencing more nightmares.⁵

Factors that are thought to contribute towards these underlying mechanisms of hyperarousal and impaired fear extinction include:

• Development of maladaptive beliefs about the nightmares – such as the idea that suppressing negative thoughts and unwanted feelings will decrease the nightmares, but actually has the opposite effect increasing the likelihood of such thoughts recurring in one’s dreams^6,12
• Traumatic experiences and childhood adversity – adverse lived experiences can disrupt one’s emotional regulation (the ability to maintain control over one’s emotions) in later life. Also, post-traumatic stress disorder (PTSD) has nightmares as a common symptom^7,30
• Heightened susceptibility – some people are acutely sensitive to both positive and negative sensory and emotional stimuli, leading to not only rich, positive daytime and dreaming experiences but also an increased likelihood of negative emotional distress and nightmare disorder⁷ 
• Stress and anxiety – experiencing anxiety is associated with an increased risk of nightmares⁷
• Drugs (recreational and therapeutic) – alter neurochemistry in the brain through neurotransmitters (i.e., the brain’s chemical messengers). Examples of therapeutic drugs having an impact include antidepressants, anti-hypertensives (e.g., beta-blockers), sedatives, and anti-parkinsonian drugs¹²
• Substance withdrawal – withdrawing and abstaining from substances such as alcohol, recreational drugs and therapeutic drugs can result in nightmares. A side effect of some medications is that they suppress REM sleep so getting off these drugs results in a rebound in REM sleep which causes nightmares⁸
• Sleep fragmentation and deprivation – due to obstructive sleep apnoea and other sleep-related disorders. Also, irregular sleep schedules, in terms of waking and sleeping times, and disrupted durations of sleep increased the risk of having nightmares
• Other disorders – comorbidity refers to the simultaneous presence of two or more disorders or conditions in the same individual. Other mental health disorders and medical conditions can be comorbid with nightmare disorder, examples of such conditions include: 
  • Post-traumatic stress disorder (PTSD)
  • Anxiety disorders
  • Depressive disorders
  • Suicidality
  • Borderline personality disorder (BPD)
  • Dissociative disorders^9,10

The theoretical framework called the ‘cognitive model of recurrent dreams’ attests that a ‘nightmare script’ is constructed from recurrent nightmare elements, and this script is repeatedly triggered in response to dream elements that resemble the original stressor.¹¹ Consequently, nightmares continue to happen even after the original stressor has faded. So, people are trapped within this vicious cycle.¹²

Management and treatment of nightmare disorder

Whilst the occasional nightmare episode doesn’t require any explicit treatment and can sometimes resolve on its own over time, some people may need clinical interventions, lifestyle changes, or help through medication to alleviate the impact nightmare disorders have on them and their lives.

There are numerous treatment options available, however, finding what works best for you and constructing a tailored plan that best suits your needs is achievable in collaboration with your healthcare professional. Treating and managing the condition offers significant benefits as it can help an individual regain some control and restore functionality in their lives.⁸

Specific available treatment options are: 

1. Psychotherapies (talk therapies) – often involve Cognitive behavioural therapy (CBT)-based approaches, including:

• Imagery rehearsal therapy (IRT) – a form of CBT where an individual recollects and imagines a specific nightmare they have had in order to rewrite it in a more positive way as though they are converting this nightmare into a new upbeat dream¹³
• Exposure, relaxation and rescripting therapy (ERRT) – a form of CBT specifically for trauma-related nightmares. It works by teaching individuals techniques to self-soothe during the revisitation of their nightmares, whilst also informing them about healthy sleeping habits and trauma management techniques¹⁴
• Systematic desensitisation therapy – helps individuals to unlearn their responses to particular situations or triggers. In this context, desensitisation works by deliberately exposing yourself to the stressors that trigger or appear in one’s nightmares and learning relaxation techniques to minimise how impactful such nightmares are¹⁵

2. Psychotropic medications (drugs) – are rarely used to treat nightmares given that it’s not always helpful and can instead contribute towards perpetuating nightmares. Nevertheless, some of the following drugs can be prescribed to help those in more severe cases:

• Tricyclic antidepressants – an REM suppressant that inhibits individuals from entering REM sleep which is where these vivid nightmares take place
• Prazosin – an anti-hypertensive that increases sleep duration and sleep quality whilst decreasing sleep disturbances. Helpful in cases where nightmares are associated with PTSD¹⁶
• Triazolam – a benzodiazepine that is commonly used to treat insomnia (i.e., trouble sleeping)
• Nitrazepam – a benzodiazepine that increases sleep duration and shortens sleep initiation (i.e., the length of time to fall asleep)

3. Various medications that can be taken to treat PTSD-associated nightmare disorder:

• Atypical antipsychotics – Aripiprazole,¹⁷ Olanzapine,¹⁸ 
• Risperidone¹⁹
• Vasodilator – Clonidine ²⁰
• Antihistamine – Cyproheptadine ²¹
• Antidepressants – Fluvoxamine,²² Phenelzine,²³ other tricyclic antidepressants
• Anticonvulsant – Gabapentin ²⁴
• Antiemetic – Nabilone ²⁵
• Antiepileptic – Topiramate ²⁶

4. Improving sleeping habits – adhering to a regular sleep routine/schedule and maintaining good sleep hygiene each night.

For parents, additional tips for kids who experience nightmare disorder include:

• Offering reassurances – responding positively, calmly and promptly to soothe the child after they wake from a nightmare may help de-escalate the situation, and their emotions, help prevent future nightmares, and help them get back to sleep
• Talking about the dream – asking the child what happened and what was so scary. This allows space to remind them that nightmares are fictional, not real and therefore cannot hurt them. This is essentially restoring the feelings of safety and comfort in the child
• Rewriting the ending – actively attempting to extinguish the fear associated with nightmares by talking through them and re-writing them with a positive ending may help reduce the nightmare’s recurrence
• Using a night light and constructing a relaxing bedtime routine – helps to minimise stress and anxious feelings children may have at night time

Prognosis

The prognosis (i.e., outlook) for nightmare disorder varies depending on the individual, the severity of their case and how responsive they are to treatment.

For children, the prognosis is typically good as kids tend to grow out of experiencing nightmares, so their symptoms should self-resolve as time passes. However, if this does not happen and symptoms persist beyond the age of 6 years, then there may be a more significant underlying cause that would need to be directly identified and addressed.

For adults, again, nightmare disorder may resolve itself. However, it could also persist for years if it is left untreated.²⁷ Given the significant consequences that nightmare disorder brings it is vital that help is sought out should it be a persistent problem. However, even though specific treatment options are available, patients are often untreated or treated sub-optimally.²⁸

When should I see a doctor?

A doctor and healthcare professional should be consulted if:

• You suspect that you may have nightmare disorder and wish to obtain a diagnosis
• You are experiencing symptoms that are disruptive to your lifestyle and are impeding your ability to function adequately day-to-day
• You wish to make amendments to your treatment plan or have any issues with your current plan
• You are concerned and wish to seek medical advice

Summary

Nightmare disorder is a relatively rare type of parasomnia that refers to individuals experiencing recurrent, frequent and extended nightmares involving a threat to the life, safety and wellbeing of themselves or those they care about. 

Nightmare disorder can have such a profound impact on the psychological and physical wellbeing of the sufferer that it can disrupt their ability to function adequately day-to-day. Because of this, treatment may be required to ensure individuals are managing their condition as best they can to maintain optimal functionality and stop the reduction in their quality of life. Various treatment options are available involving a range of psychotherapeutic techniques, medications and sleep behaviour modifications.