Published on: 6/20/2025
What could cause sudden tiredness during the day?
Sudden tiredness during the day can be caused by neurological issues, vitamin B12 deficiency, or other medical factors affecting sleep.
Explanation
Sudden tiredness during the day can happen for several reasons. One possible cause is neurological issues, which can lead to excessive daytime sleepiness and fatigue. This means that problems with the brain or nerves might make you feel very sleepy during the day, even if you slept well at night.
Another reason for feeling tired suddenly could be a lack of vitamin B12. Vitamin B12 is important for your body to work well, and not having enough of it can make you feel sleepy and tired during the day.
Lastly, other medical factors can also cause you to feel sleepy suddenly. For example, some people might feel very sleepy when driving, which can be dangerous. This could be due to different health issues that affect how well you sleep and how awake you feel during the day.
If you find yourself feeling tired often during the day, it might be helpful to talk to a doctor to find out why. They can help figure out if it's because of one of these reasons or something else.
(References)
- Maestri M, Romigi A, Schirru A, Fabbrini M, Gori S, Bonuccelli U, & Bonanni E. (2020). Excessive daytime sleepiness and fatigue in neurological .... Sleep & breathing = Schlaf & Atmung, 31444679.
- Khawaja I, Yingling K, Bukamur H, & Abusnina W. (2019). Vitamin B12 Deficiency: A Rare Cause of Excessive .... Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine, 31538608.
- Volná J, & Sonka K. (2006). Medical factors of falling asleep behind the wheel. Prague medical report, 17385401.
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