Nightmares: Why They Happen and How to Stop Them

What Are Nightmares?

A nightmare is a vivid, disturbing dream that often wakes you up. Common themes include being chased, falling, being attacked, losing someone close or failing at something important. When you wake, you usually remember the dream clearly and may feel scared, anxious, sad or angry. Your heart may be racing and it can take a while to fall back asleep.

Nightmares mostly happen during REM sleep, the stage of sleep linked with vivid dreaming. Because REM periods get longer as the night goes on, nightmares are more likely in the second half of the night and the early morning hours.

How Common Are Nightmares?

Bad dreams are a normal part of life. Most adults have an occasional nightmare, and they're particularly common in children, often starting between the ages of about 3 and 6 and becoming less frequent with age. For most people, nightmares are rare and don't cause problems. A smaller number of adults have nightmares so often, or so upsetting, that they affect sleep, mood and daily life. When this happens, doctors may call it nightmare disorder.

Nightmares vs Night Terrors

Nightmares and night terrors are often confused, but they're different. Nightmares happen during REM sleep, the person usually wakes up fully and they can remember the dream. Night terrors happen during deep non-REM sleep, usually in the first few hours of the night. A person having a night terror may scream, thrash or sit up looking terrified, but they are hard to wake and usually don't remember anything in the morning. Night terrors are most common in young children.

What Causes Nightmares?

Stress and anxiety

Everyday worries about work, exams, money or relationships are among the most common triggers. Big life changes, such as moving house, a new job or losing someone, can bring on a phase of bad dreams.

Trauma

People who have been through a frightening or painful event may have repeated nightmares about it. Frequent trauma-related nightmares are a common feature of post-traumatic stress disorder (PTSD).

Poor or irregular sleep

Not getting enough sleep, frequent changes to your sleep schedule and jet lag can make nightmares more likely. After a period of short sleep, the body may catch up with extra REM sleep, which can bring intense dreams.

Medicines and substances

Some medicines, including certain antidepressants, blood pressure medicines and drugs that act on the brain, can cause vivid dreams or nightmares. Alcohol can disturb REM sleep, and stopping alcohol or some medicines suddenly can also trigger bad dreams.

Mental health conditions

Depression and anxiety disorders are linked with more frequent nightmares.

Other sleep disorders

Conditions such as sleep apnoea, which repeatedly disturb sleep, are sometimes linked with nightmares.

Scary content and late eating

Watching a frightening film or reading something upsetting before bed may influence your dreams. Some people find that heavy late-night meals lead to more disturbed sleep and dreams, though the research here is limited.

How to Have Fewer Nightmares

Start with the basics of good sleep. Keep a regular bedtime and wake-up time, and aim for seven to nine hours of sleep. Make your bedroom cool, dark and quiet, and keep it a calm place linked with rest.

Create a relaxing routine for the last hour before bed. Put away screens, avoid stressful conversations and work emails, and choose calm activities such as reading, gentle stretching or slow breathing. If worries race through your mind, try writing them down before bed so they feel less pressing.

Limit alcohol and caffeine, especially in the evening, and avoid heavy meals late at night. Regular exercise during the day can help lower stress and improve sleep, but try to finish vigorous workouts a few hours before bed.

What to Do After a Nightmare

If you wake from a nightmare, remind yourself that it was a dream and you're safe. Take a few slow, deep breaths, breathing out for longer than you breathe in. Turn on a soft light if it helps, drink a little water and do something calm for a few minutes before trying to sleep again. Avoid picking up your phone and scrolling.

For children, comfort and reassurance are the most important things. Stay with them for a few minutes, keep your voice calm and help them settle back to sleep. A night light can help some children feel safer.

Treatment for Frequent Nightmares

If nightmares happen often and affect your sleep or daily life, effective help is available. A well-studied treatment is imagery rehearsal therapy. In this approach, you write down a recurring nightmare, change the story to something less upsetting and then practise the new version in your mind during the day. Over time, this can reduce how often the nightmare happens and how distressing it feels. The American Academy of Sleep Medicine recommends this therapy for adults with nightmare disorder, including nightmares linked with PTSD. Other options include cognitive behavioural therapy, treating any underlying condition and, in some cases, medicine prescribed by a doctor.

When to See a Doctor

See a doctor if you have nightmares several times a week, if fear of nightmares makes you avoid sleep, if they cause daytime tiredness or distress, or if they began after a traumatic event or a new medicine. Seek help for a child whose nightmares are frequent, very distressing or come with other worrying changes in behaviour.

How Habuild Can Help

Habuild's live sessions combine yoga, exercise and breathing, which can help you manage stress and sleep better. The Habuild app's Box Breathing habit is a calm way to relax before bed.

Editorial Sources

• •Morgenthaler et al. – Position Paper for the Treatment of Nightmare Disorder in Adults: An American Academy of Sleep Medicine Position Paper, Journal of Clinical Sleep Medicine (2018)
• •Mayo Clinic – Nightmare disorder: Symptoms and causes
• •Cleveland Clinic – Nightmare Disorder
• •NHS – Night terrors and nightmares

Health Disclaimer

This article is for general information only and is not medical advice. If nightmares are frequent or affect your daily life, please consult a doctor or mental health professional.