What causes sleep paralysis?
Experts don’t yet understand what exactly causes sleep paralysis — a phenomenon in which you can’t move as you wake up or fall asleep. During sleep paralysis, your muscles are frozen in place, which usually only happens when you reach rapid eye movement (REM) sleep.
Sleep paralysis risk factors
Certain factors can increase the chances that you experience sleep paralysis. These include:
- Getting too little sleep
- Having a frequently changing sleep schedule
- Sleeping on your back
- Stress, anxiety, post-traumatic stress disorder (PTSD), or other mental health conditions
- Sleep disorders like narcolepsy
- Using certain medications
- Drinking alcohol or using drugs
- Having family members who experience sleep paralysis
Medically reviewed by
Dr. Colleen Ehrnstrom is a licensed clinical psychologist with a specialty practice in Acceptance and Commitment Therapy (ACT). Areas of expertise include insomnia and other sleep disorders, anxiety, and depression.
Dr Ehrnstrom is the co-author of the book End the Insomnia Struggle: A Step by Step Guide to Help you Get to Sleep and Stay Asleep which offers a comprehensive, personalized sleep program that integrates the physiology of sleep, cognitive behavioral therapy for insomnia (CBT-I) and acceptance and commitment therapy (ACT).