7 Reasons for Feeling Sleepy or Tired During the Daytime

Sleep Apnea, Narcolepsy, and Sleep Deprivation May Cause Excessive Sleepiness

If you always have trouble staying awake during the daytime, suffer from excessive daytime sleepiness or drowsiness, easily doze off, take naps on a regular basis, and have difficulty with attention or concentration, you may wonder: Why do I feel sleepy all the time? Some sleep disorders, such as insomnia, make it so you can't sleep, while many others result in poor sleep quality. Discover 7 common reasons for feeling or being too sleepy during the daytime, including the most common sleep disorder causes affecting sleep quality such as sleep apnea and narcolepsy.

1
Poor Sleep Habits

A woman yawns over coffee due to being sleepy from poor sleep habits
A woman yawns over coffee due to being sleepy from poor sleep habits. Tetra Images - Jamie Grill/Brand X Pictures/Getty Images

The most common cause of always feeling too sleepy or drowsy during the daytime might be the most obvious: you are simply not getting enough sleep at night. You may not know exactly how much sleep you need. And if you do know, you may choose to not sleep enough because of work or social obligations, which is sometimes called sleep restriction. You could be trying to sleep in a poor sleep environment, such as leaving the television on at night, that is not conducive to sound sleep. You may have a horrible bedtime routine that does not prepare you well to fall asleep. You may also fail to follow any of the other simple guidelines to improve your sleep, such as avoiding caffeine and alcohol near bedtime. Any and all of these things may leave you too sleepy the next day, without any specific sleep disorder as the cause.

More

2
Sleep Apnea

A man treats his sleep apnea with CPAP therapy to reduce daytime sleepiness
A man treats his sleep apnea with CPAP therapy to reduce daytime sleepiness. Science Picture Co/Getty Images

Sleep apnea is a condition in which you repeatedly partially or completely stop breathing while asleep. This may result in witnessed pauses followed by a loud snort and brief awakening as you gasp for air. It can occur dozens or even a hundred times per hour of sleep. With each awakening, you shift briefly into lighter stages of sleep. You may wake completely and fall back asleep without remembering it. This disruption leads to sleep fragmentation and poor quality sleep and results in significant excessive daytime sleepiness. People with severe sleep apnea are at increased risk for falling asleep while driving.

A similar condition called upper airway resistance syndrome (UARS), in which the breathing disturbances are less pronounced during sleep, can also be problematic. There are also serious health consequences to sleep apnea, so treatment such as the use of continuous positive airway pressure (CPAP) therapy or the use of an oral appliance, should be pursued.

More

3
Narcolepsy

Waking with sleep paralysis is one symptom of narcolepsy, that also causes sleepiness
Waking with sleep paralysis is one symptom of narcolepsy, that also causes sleepiness. Vladimir Godnik/Getty Images

There are four defining symptoms of narcolepsy, the least specific being excessive sleepiness. This sleep disorder occurs when there is a problem with the regulation of sleep and wakefulness. Therefore, characteristics of sleep may suddenly occur while awake (such as paralysis) and elements of wakefulness may intrude upon sleep. The most characteristic symptom of narcolepsy is cataplexy, which is the sudden loss of muscle tone with an emotional stimulus such as surprise or laughter. The sleepiness associated with narcolepsy may require treatment with stimulants such as Ritalin, Provigil, and Nuvigil.

More

4
Chronic Fatigue Syndrome

A man sleeps during the day due to chronic fatigue syndrome causing sleepiness
A man sleeps during the day due to chronic fatigue syndrome causing sleepiness. Jena Cumbo/The Image Bank/Getty Images

Chronic fatigue syndrome is a condition that might make you feel tired, exhausted, or sleepy. It is characterized by worsened fatigue that occurs after exertion, associated with unrefreshing sleep and often joint and muscle pains. Although the cause of chronic fatigue syndrome is not completely understood ​and may be due to subtle sleep apnea, it can lead to significant impairment and disruption of the affected person's life.

More

5
Kleine-Levin Syndrome

Children may rarely suffer from Kleine-Levin syndrome as a cause of sleepiness
Children may rarely suffer from Kleine-Levin syndrome as a cause of sleepiness. Getty Images

Although quite rare, Kleine-Levin syndrome is a condition that may affect young adults and can cause recurrent episodes of excessive sleepiness. These episodes can last for days, weeks, or even months at a time. The sleepiness can be incapacitating. It often interferes with school attendance and basic daily functions. There may be associated symptoms, such as hallucinations or hypersexual or compulsive behaviors. The only treatment known to be beneficial in the treatment of Kleine-Levin syndrome is the mood stabilizer called lithium, though it has mixed benefits in some studies.

More

6
Restless Legs Syndrome

Restless legs syndrome can make it hard to sleep and lead to sleepiness
Restless legs syndrome can make it hard to sleep and lead to sleepiness. Stephanie Phillips/E+/Getty Images

Disorders that cause excessive movements during sleep may lead you to feel sleepy the next day. The most common condition is often linked to restless legs syndrome (RLS). This disorder is characterized by an uncomfortable sensation in the legs associated with an urge to move that often develops in the evening as you are lying down to rest and is relieved by movement.

The commonly associated condition, called periodic limb movement syndrome (PLMS), is diagnosed when there are sudden jerking movements that occur during sleep. These may be repetitive and disturb the sleep of the affected person as well as potentially disrupting the sleep of their bed partner. There are effective treatments available for these conditions, depending on the underlying cause.

More

7
Circadian Rhythm Disorders

Circadian rhythm disorders may lead to both sleepiness and insomnia at different times
Circadian rhythm disorders may lead to both sleepiness and insomnia at different times. Funky Illustrations from Holland/Moment/Getty Images

Various circadian rhythm disorders may leave you feeling too sleepy. The circadian rhythm is the body's natural clock that helps to coordinate your activities to the timing of light and dark in your environment. If this timing is misaligned, you may find yourself sleepy at inappropriate times.

For example, if you have advanced sleep phase syndrome, you will feel sleepy in the evening. Conversely, with delayed sleep phase syndrome, you will have difficulty falling asleep (or insomnia) and feel sleepy in the morning. People with the first condition are called morning larks and those with the second condition are called night owls. Fortunately, there are effective treatments like light therapy and the use of melatonin for these and other circadian rhythm conditions, including jet lag and seasonal affective disorder (SAD).

More

Get Additional Help

If you continue to struggle with daytime sleepiness, seek a comprehensive evaluation by a board-certified sleep specialist. You can finally get the quality sleep that you need to wake and feel rested and function at your best every day.

Continue Reading