Sleep paralysis is a temporary inability to move or speak that happens when you are waking up or, less commonly, falling asleep.
Although you are awake, your body is briefly paralysed, after which you can move and speak as normal. The paralysis can last from a few seconds to several minutes.
Sleep paralysis does not harm your body, but not being able to move can be very frightening.
Some people have sleep paralysis once or twice in their life, while others experience it a few times a month or more regularly.
Why does sleep paralysis happen?
It is normal for your muscles to be paralysed at certain times when you are asleep. Sleep paralysis occurs when the mechanism that causes your muscles to relax during sleep temporarily persists after you have woken up.
Sometimes, sleep paralysis can be a symptom of narcolepsy. Narcolepsy is a relatively rare sleep disorder that causes a person to fall asleep suddenly and unexpectedly, disrupting their normal sleep pattern.
Other risk factors for sleep paralysis include:
- sleep deprivation
- a possible family tendency towards the condition
Who is affected?
Sleep paralysis may affect people of any age, but it is more common in teenagers and young adults.
Estimates of the number of people affected by sleep paralysis vary, but one study found that around 6% of people will experience at least one episode of sleep paralysis in their life.
Sleep paralysis does not affect your general physical health and the symptoms can often be improved by improving your sleep habits and sleeping environment.
In severe cases, your GP may suggest that you try taking a certain type of antidepressant medication for a month or two, to see if this improves the condition.