It used to happen to me quite often, but only if I took a nap sometime during the day before going to bed. If I didn't take a nap, it wouldn't happen.. strange..
When it did happen.. couldn't move, couldn't yell out..
I'd usually just stop fighting it, then try to jerk real quick and that usually worked....
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about sleep paralysis?
Some people with disrupted sleep schedules or circadian rhythm disturbances experience sleep paralysis
A study found that 35% of subjects with isolated sleep paralysis also reported a history of wake panic attacks unrelated to the experience of paralysis
Sixteen percent of these persons with isolated sleep paralysis met the criteria for panic disorder
How can I stop the sleep paralysis?
In severe cases, where episodes take place at least once a week for 6 months, medication may be used.
You may be able to minimize the episodes by following good sleep hygiene:
getting enough sleep
reduce stress
exercise regularly (but not too close to bedtime)
keep a regular sleep schedule
More on sleep paralysis