Should you wake a sleepwalking person or leave them?

Sleepwalking is one of those “strange but true” phenomena, and in extreme cases, people have even been reported driving cars.

Their eyes may be closed or open — often with a somewhat glazed expression — but, despite the stereotypical image, sleepwalkers don’t normally walk with their arms outstretched.

So, should you wake someone who is sleepwalking, or leave them be?

Don’t shake or hit a sleepwalker

The common idea is that it’s dangerous to wake a sleepwalker because you could cause them harm, perhaps by triggering a heart attack or a level of shock so intense it could kill them.

But is this the case?

Harriet Hiscock, a consultant paediatrician with the Murdoch Children’s Research Institute, says while it’s true it’s best not to wake a sleepwalker, the heart attack and “killer shock” part of the story is a myth.

“When someone is sleepwalking, they’re stuck between deep sleep and light sleep and if you try to wake them up, they will be very confused and disorientated,” Professor Hiscock says.

“You’re not going to give them a heart attack or kill them, but by trying to wake them up — which is usually quite hard to do — you can make them very agitated.”

She advises against waking a person if you can avoid it.

How to wake up a sleepwalker

But what if leaving a sleepwalker to their own devices isn’t an option? What if they’re heading out into the street or getting into a car, for instance?

Professor Hiscock advises gently taking a person’s hand or elbow without waking them and guiding them back to where they should be.

“They might actually talk to you and it might not make much sense but if you don’t wake them up completely, they usually won’t remember anything the next day,” she says.

If you’re having trouble getting a sleepwalker out of harm’s way, it is best to wake them — but do it by calling their name or speaking loudly rather than by shaking or hitting them.

Children more likely to sleepwalk

The experience of waking from a sleepwalking episode can be likened to the disorientation experienced when you’re woken from a very deep sleep by a sudden, loud noise.

It’s known as sleep inertia and it usually takes a while to orientate yourself and understand what’s happening.

It can then take some time to return to sleep, which is one reason waking a sleepwalker isn’t routinely recommended; it cuts into their sleep time and may leave them sleep deprived by morning.

The National Sleep Foundation says sleepwalking (or somnambulism) is more common in young children than adults and usually becomes less frequent as they get older.

Professor Hiscock says between 2 and 5 per cent of adults are sleepwalkers.

“It’s not really clear why some people get up and sleepwalk and others don’t,” Professor Hiscock says, adding that it’s linked to some genes so it does tend to run in families.

She says sleepwalking usually occurs when people are transitioning between deep and light sleep.

“Their body is awake and they’re walking or talking or may be picking at things with their hands, but their mind is still not fully awake,” she says.

“If you just let them be, they would naturally come up into a light sleep and then go back into deep sleep again without fully waking.”

ABC Everyday in your inbox

Get our newsletter for the best of ABC Everyday each week

Steps to take to protect sleepwalkers

If you have an active sleepwalker in the house, Professor Hiscock recommends taking safety measures such as locking windows and doors, removing sharp objects from the bedroom, and avoiding bunk beds for younger sleepwalkers.

If a child is regularly sleepwalking and getting into potentially dangerous situations, Professor Hiscock says “scheduled awakening” may help.

This means recording the time your child tends to sleepwalk — if it’s consistent — or the time between them falling asleep and starting to sleepwalk.

Then, wake them 20 minutes before their sleepwalking is due to start.

Once they’re awake, let them go back to sleep.

“That resets their sleep cycle so they go back to sleep again and hopefully sleep through the period when they would have been sleepwalking,” Professor Hiscock says.

The scheduled waking should be continued nightly for several weeks.

Often, this leads to the sleepwalking behaviour disappearing for good.

For older children and adults, hypnosis is sometimes a helpful treatment, as is treating any co-occurring sleep problems, such as sleep apnoea or restless legs syndrome, Professor Hiscock says.

This is general information only. For detailed personal advice, you should see a qualified medical practitioner who knows your medical history.

This story, which was originally written by Lydia Hales and published by ABC Health and Wellbeing, was updated in 2019.