It may seem like an odd thing to consider, but what is sleepiness and what causes it?
Does sleepiness suggest the presence of certainsleep disorderslike sleep apnea or narcolepsy?
And how doessleepiness differ from fatigueor tiredness?
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Let’s find out.
What Is Sleepiness?
Sleepiness is the desire to fall asleep.
It is sometimes referred to as drowsiness and typically increases the longer we stay awake.
You’re reading a boring book or listening to an uninteresting television program.
Your eyelids are getting heavy.
A warm feeling comes over you.
You are about to doze off.
(Interestingly, caffeine works by blocking the action of adenosine within the brain, leading to wakefulness.
Alcohol enhances it and contributes to feeling sleepy.
)Sleepiness may occur normally or be due to an underlying sleep disorder.
People feel sleepy every day, especially before sleep onset.
The degree of sleepiness or drowsiness may increase the longer you stay awake.
This relates to the role of the circadian rhythm.Sleepiness may also be worse during periods of sleep deprivation.
If poor quality sleep is obtained, you may feel more sleepy during the day.
Each of these conditions leads to sleep fragmentation, which disrupts the restorative process of sleep.
Some people have sleepiness without a clear cause as a result of a condition called idiopathic hypersomnia.
After eating a meal, feeling drowsy is calledpost-prandial sleepiness.
Sleepiness or Fatigue?
It’s important to differentiate sleepiness or drowsiness from fatigue or tiredness.
In the realm of sleep problems, fatigue is a common complaint of insomnia.
There are some ways to avoid sleepiness.
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