What is shift work sleep disorder (SWSD)?

Shift work sleep disorder (SWSD) is a sleep disorder that commonly affects those who work non-traditional hours, outside the typical 9 a.m. to 5 p.m. work day. Shift work schedules go against most peoples’ internal body clocks or circadian rhythms. SWSD causes difficulties adjusting to a different sleep/wake schedule, which results in significant issues with falling asleep, staying asleep, and sleeping when desired. About 20% of the fulltime workforce in the US is involved in some form of shift work.

What are the symptoms of shift work sleep disorder (SWSD)?

The most common symptoms of SWSD are difficulty sleeping and excessive sleepiness. Other symptoms associated with SWSD can include difficulty concentrating, headaches, or lack of energy.

Not every shift worker suffers from SWSD. It is estimated that 10% to 40% of shift workers have SWSD. If you are a shift worker experiencing any of these symptoms, talk to your doctor.

What are the consequences of shift work sleep disorder (SWSD)?

Increased likelihood of:

  • Accidents and work-related errors
  • Irritability or mood problems
  • Poor coping skills and impaired social functioning
  • Health related complaints — including gastrointestinal, cardiovascular, and metabolic problems
  • Drug and alcohol dependency

Last reviewed by a Cleveland Clinic medical professional on 04/22/2017.


  • National Sleep Foundation. Shift Work Disorder Accessed 8/11/2020.
  • American Academy of Sleep Medicine. Shift Work Accessed 8/11/2020.
  • American Academy of Sleep Medicine. International classification of sleep disorders, 3rd ed. Darien, IL: American Academy of Sleep Medicine, 2014.

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