Introduction

Did a terrible dream wake you up in the middle of the night? Or did your child’s screams in their sleep terrify you?
Was it just a nightmare or something more terrifying, such as a night terror?

These two terms are often used interchangeably, but they are not similar.

In this article, we’ll explore the key differences between nightmare disorder and night terrors, along with their causes, symptoms, risk factors, and treatment options, so you can better understand what’s really happening and how to manage it.

Definitions and overview

Nightmare disorder 

Nightmares are vivid, unpleasant, or scary dreams that can cause distress and are often threatening and make you feel unsafe.

These dreams typically occur in the second half of the night during REM (rapid eye movement) sleep, and people usually wake up fully alert and can clearly recall the content of the dream.

When nightmares happen frequently (more than once a week) and start affecting daily life, like interfering with school, work, or social relationships, it may be diagnosed as nightmare disorder.¹

Night terrors 

Also known as sleep terrors, these episodes usually affect children.²

During an episode , a child may suddenly sit up in bed, scream, cry, and look terrified. They may be very hard to wake and often don’t respond to comfort, and even if they wake up, they are confused and inconsolable.³

Night terrors occur in the early part of the night, that is, 2-3 hours after sleeping during NREM (non-rapid eye movement) sleep. Most children don’t remember the event the next morning after waking up.⁴

Sleep stage differences 

There are two main stages of sleep : REM and NREM

REM (rapid eye movement) 

In this stage, your eyes move rapidly when closed, and your brain is active, just like when you are awake. Dreams happen during this stage.

Nightmares occur during this stage.⁵

Non-REM 

It is a deep sleeping stage; your body relaxes, and your heartbeat and breathing slow down. It is harder to wake someone during this stage.

Night terrors occur during this stage.⁴

Age and sex

Nightmare disorder

Nightmares can affect both children and adults. 

They usually begin around age 3, peak between ages 6 to 10, and decrease with age. About 50% of children have had at least one nightmare, and up to 20% experience them frequently.⁶

In 85% of adults, nightmares occur once per year; 2–6% experience nightmares weekly, and 35–45% have a nightmare once per month.⁷

Nightmares are more common in women during adolescence and adulthood, but this gender difference isn’t as noticeable in young children or older adults.⁸

Night terrors 

Night terrors are most common in children aged 1 to 5 years but can occur anytime between ages 18 months and adolescence. The symptoms and frequency of episodes tend to fade with growth and then disappear after puberty.^2,9

Although rare in adults, when they do occur, they may be linked to PTSD or psychiatric conditions.³

In children it is more common in boys, while in adults both sexes are affected equally.⁴

Key symptoms and clinical features

Nightmare disorder

Nightmares are disturbing and vivid dreams that often wake a person up. After waking, the person is fully alert.¹

Nightmares tend to occur late in the night or in the early morning and are remembered clearly after waking.⁴

The main emotion is fear, but sadness, anger, or shame can also be felt.⁸

Physical symptoms like a rapid heartbeat and sweating can occur during the nightmare or after waking up or recalling it.^1,5

Common themes include being chased, falling, losing loved ones, or being late. Children may dream of monsters and fantasy scenes , while adults often have more realistic nightmares.^8,9

Affected people might fear going back to sleep due to fear of nightmares.¹⁰

Frequent nightmares can affect work, school, and relationships and lead to daytime issues like tiredness, low energy, trouble focusing, and irritability.¹

Nightmares can be categorized as :

• Mild : occur less than once a week¹
• Moderate : occur more than once a week but not nightly¹
• Severe : occur every night¹

Night terror

Night terrors begin with a sudden awakening marked by screams, confusion, and fear. The child appears confused, frightened, and hard to comfort, but they aren’t fully awake and don’t remember the episode later.²

They seem disoriented and may thrash or run around, which can sometimes lead to injury. These episodes typically happen 2 to 3 hours after falling asleep and can last from 30 seconds to 30 minutes.⁹

Physical signs include rapid heartbeat, sweating, and dilated pupils are common, and sometimes a glassy stare or incoherent speech might also be present.^4,9

Night terrors rarely happen during naps and usually occur once per night but can occasionally happen more than once.⁴

Underlying causes and risk factors 

Nightmare disorder

• Stress: Nightmares can both result from and contribute to stress
• Past trauma: Emotional or physical trauma, especially in PTSD or acute stress disorder
• Psychiatric disorders: Depression, anxiety, panic disorder, schizophrenia, dissociative disorders, and borderline personality disorder
• Medications: Certain drugs like beta blockers (used for blood pressure), dopamine agonists (used for Parkinson’s), antidepressants, and some antibiotics
• Withdrawal effects : Withdrawal from certain medicines, such as benzodiazepines, barbiturates, and even alcohol withdrawal can cause nightmares
• Unknown causes: Sometimes no clear cause can be found³

Night terror

• Sleeping alone: Especially in young children
• Sleep deprivation
• Full bladder during sleep
• Family history: They often run in families
• Medications: Including neuroleptics, tricyclic antidepressants, sedatives, stimulants, clonidine, opiates, and antihistamines
• Psychiatric conditions: PTSD, anxiety, depression, ADHD, autism, and bipolar disorder. Main causes in adults
• Medical conditions: Fever, sleep apnea, restless leg syndrome, nocturnal asthma, GERD, and epilepsy
• Other causes : Excess physical activity, emotional stress, bullying, loud environments, separation anxiety, and excessive caffeine use^2,4,9

Diagnosis

Nightmare disorder 

Diagnosis is based on clinical history.

Polysomnography (PSG) can be performed to rule out other sleep disorders.³

Night terrors

• The diagnosis for night terrors is also based on the history provided by the parents or family members
• Video recordings of the event and a sleep diary can be helpful
• Complete physical examination : To rule out any developmental and neurological issues
• Video-polysomnography is reserved for severe and inconclusive cases⁴

Treatment

Nightmare disorder

In many cases, treatment isn’t necessary. Even individuals diagnosed with nightmare disorder may notice improvement over time without intervention. 

However, certain strategies can help reduce the frequency and severity of nightmares:

Lifestyle and sleep hygiene:

• Maintain a consistent sleep schedule
• Avoid caffeine and alcohol before bed
• Create a calm, safe sleep environment
• A healthy social interaction often helps in managing emotions
• Exercise regularly
• Hunger can also affect sleep therefore, don’t skip meals
• Avoid screens before bedtim.³

Managing Underlying Causes: Seek treatment for any associated mental health conditions, and if medications are causing nightmares, discontinue them gradually under medical guidance.³

Therapies:

• Imagery Rehearsal Therapy (IRT)
• Cognitive Behavioral Therapy (CBT)³
• Psychodynamic Therapy
• Exposure Therapy
• Lucid Dreaming Therapy¹

Medications: Usually avoided, but may be considered in severe cases.

• Prazosin : helpful in PTSD
• Others like trazodone, gabapentin, or risperidone may be tried, though evidence is limited^1,3

Night terrors

Night terrors usually don’t require treatment. Most children outgrow them naturally, and support of parents is enough.⁴

What helps:

• Stay calm, avoid interference, and let the episode pass
• Gently guide the child back to bed and remove sharp/dangerous items from room
• Scheduled awakening : wake the child 30 minutes before the usual episode time
• Ensure they get enough sleep and follow a consistent bedtime routine
• Make sure that the kid goes to bed with an empty bladder
• If any medicine is causing night terrors, then let your doctor know about it^2,4

Therapy: If you suspect stress, trauma, or psychiatric issues, therapy may be helpful. Such as :

• Psychotherapy
• Relaxation techniques
• Hypnosis^9,11

Medications : Generally avoided in children unless the episodes are severe or dangerous. In such cases:

• Clonazepam may be used for short-term
• Other options include diazepam, imipramine, clomipramine, or paroxetine^4,9

Summary 

Nightmares and night terrors are both sleep disturbances, but they are very different in how they appear, what causes them, and how they affect people. Nightmares are disturbing dreams that occur during REM sleep and often wake the person, who can usually remember the dream clearly. When frequent and distressing, they may be diagnosed as nightmare disorder. These are common in both children and adults and are often linked to stress, trauma, psychiatric issues, or medications.

Night terrors affect children and happen during NREM sleep. A child may scream and appear terrified; they are hard to wake up and don’t remember the event. While upsetting, night terrors are usually harmless and fade with age. They can be triggered by factors like sleep deprivation, stress, and other health issues and rarely need treatment.

Managing both conditions involves improving sleep hygiene, identifying underlying causes, and using therapies in severe cases. Medication is only used when absolutely necessary.