So what should you do if you find your relative sleepwalking?
For a start, they are in such a deep sleep that they will probably not notice you, even if you try to wake them. If you do succeed in waking them you might disorientate them to the extent that they become distressed. Everyone has experienced that feeling of utter bewilderment when the alarm awakens you from deep sleep, instead of the lighter sleep we are usually experiencing by the time our alarms sound. I once had the shock of being woken by a crash and found myself in the kitchen, standing barefoot and surrounded by broken glass. I’d tried to get a glass of water while sleepwalking, but like most sleepwalkers I failed to turn on the light, and had smashed the glass against the tap.
So waking a sleepwalker will not cause them to have a heart attack or put them into a coma, but the kindest thing to do is not to try to wake them at all. Lead them gently back to bed so that they do not hurt themselves. They will remain deeply asleep, and it is likely that they will not remember a thing in the morning.
You can hear more Medical Myths on Health Check on the BBC World Service.
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