Nightmares: What Causes Them and What Actually Helps

Nightmares can leave you wide awake at 3am with your heart racing, and a bad run of them can make you dread going to bed at all. The good news is that nightmares in adults usually have a cause you can work on, and there is a well-studied way to retrain a recurring one. This guide covers what nightmares are, what tends to trigger them, what to do in the moment, how imagery rehearsal works, what helps children, and when to see your GP.

The short answer: nightmares are vivid, frightening dreams that happen in REM sleep and wake you suddenly. Occasional nightmares are normal, especially in children. In adults they are often linked to stress, trauma, illness, medications or alcohol. Regular sleep and wake times, a calmer wind-down and less alcohol help many people. If nightmares are frequent or affecting your days, see your GP, because imagery rehearsal therapy and other treatments work.

What nightmares are

The Sleep Health Foundation describes nightmares as distressing, vividly frightening dreams that happen during REM (rapid eye movement) sleep. They usually wake you suddenly, often with fear and sometimes sweating. Because REM sleep comes around in cycles, the first one can arrive roughly 90 minutes after you fall asleep, and they can recur at roughly 90-minute intervals through the night (source). For more on that rhythm, see sleep cycles explained.

They are much more common in childhood. The same page notes that 10% to 50% of children have them, compared with 2.5% to 10% of adults. A separate study puts weekly nightmares at two to five per cent of the general population, rising to around 30% in psychiatric settings (source).

With a nightmare you usually wake fully, remember the dream and can be comforted. That's different from behaviours that happen in deep sleep, such as sleepwalking, where the person often stays asleep. For those, see sleep talking and sleepwalking.

Common triggers

The Sleep Health Foundation lists stress, trauma, mental illness, physical sickness and medications as causes. In children, nightmares can simply be part of normal development and a busy imagination. In adults they are far less common and more often linked to psychological stress or post-traumatic stress disorder.

Possible trigger	What to try
Work or money stress	A wind-down hour and a worry list written before bed
A recent traumatic event	Talk to your GP; support is available and treatment works
Alcohol in the evening	Cut back, especially in the last few hours before bed
New medication	Ask your GP or pharmacist whether nightmares are a known side effect. Don't stop a medicine without advice
Irregular sleep	Same wake time every day, weekends included
Illness or fever	Usually passes as you recover

What to do when a nightmare wakes you

The aim is to bring your body down from alarm mode and convince your brain the threat is over.

1. Orient yourself. Notice the room, the time, the sheets. Remind yourself it was a dream.
2. Slow your breathing. Long, slow out-breaths help your heart rate settle.
3. Change the scene if you need to. If you can't settle in 15 to 20 minutes, get up, sit somewhere dim and do something calm until you feel sleepy.
4. Skip the phone. Bright screens and scrolling keep you alert. See screens before bed.
5. Write it down in the morning, not at 3am. That record is useful if you try imagery rehearsal or see your GP.

If your mind keeps running after a nightmare, the techniques in racing thoughts at night can help.

Imagery rehearsal: retraining a recurring nightmare

The Sleep Health Foundation lists "learning to change the nightmare", such as changing the storyline, among the treatments, alongside counselling and, in some cases, medication. The structured version is called imagery rehearsal therapy (IRT), and a 2021 trial describes it as the best-supported psychological treatment for nightmares (source).

In that trial, the steps looked like this:

• Write down the nightmare as a story, while you're awake and calm.
• Choose a moment to change. Pick the point where you want the storyline to go differently.
• Rewrite it. Change the nightmare in your imagination until the strong emotions settle.
• Rehearse the new version daily. Sessions ranged from a couple of minutes to 20 or 30 minutes.

People who did telephone-guided IRT had much larger drops in nightmare frequency and distress than a waitlist group, and the benefits held at follow-up. It took about 45 minutes of clinician time in total. If your nightmares are linked to trauma, do this with a psychologist rather than alone, because revisiting the material can be hard.

Habits that make nightmares less likely

The Sleep Health Foundation's self-help advice is simple: relax enough in the hours before bed, keep regular sleep and wake times, reduce anxiety where you can, and avoid alcohol (source).

• A fixed wake time. It steadies your body clock and your sleep cycles. See fixed wake-up time.
• A real wind-down. Dim lights, no work email, nothing frightening on screen in the last hour. A bedtime routine for adults gives you a template.
• Less alcohol. The foundation specifically advises avoiding it if nightmares are a problem. See does alcohol help you sleep.
• Enough sleep. Some people find their nights are more unsettled when they're overtired.
• Daytime support for stress. Exercise, time outdoors and talking things through all reduce the load you take to bed.

For children, the foundation suggests quiet time before sleep. Keep bedtime calm and predictable, and comfort them back to sleep after a bad dream.

When to see your GP

See your GP if nightmares are frequent, if they keep affecting your sleep or your mood the next day, if you're avoiding sleep because of them, or if they started after a traumatic event. Your GP can review your medications and refer you to a psychologist or sleep specialist. If you are in distress, contact your GP, Beyond Blue or Lifeline. This guide is general information, not medical advice.

Where the Sovune Nudge fits

We make the Sovune Nudge, a vibrating alarm wristband, so we're not neutral. After a broken night, a blaring alarm is a harsh way to start the day. A wrist alarm can make the wake-up gentler.

• Starts as a gentle tap and builds through three intensity levels, rather than jolting you awake with noise.
• Silent. No speaker, no sound and no light in the room, so a partner who already woke with you at 3am can sleep on.
• Each alarm vibrates for a full minute, and you can switch it off sooner.
• Set on the band itself. No app and no phone, so there's no reason to pick up a bright screen in the night.

It comes with a 30-day money-back guarantee.

Quick answers

Are nightmares normal in adults? Occasional ones are. Frequent nightmares in adults are less common and are often linked to stress, trauma, illness, medications or alcohol.

Can you stop a recurring nightmare? Often, yes. Imagery rehearsal therapy, where you rewrite the nightmare while awake and rehearse the new version daily, has good evidence.

Should I wake someone having a nightmare? If they're distressed, gently comforting them is fine. Most people wake from a nightmare on their own and can be settled.

Does alcohol cause nightmares? It isn't the only cause, but the Sleep Health Foundation advises avoiding alcohol if you have nightmares.

For every type of silent alarm compared, see our complete guide to vibrating alarms in Australia.

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