Causes of Excessive Sleepiness: Sleep Apnea, Narcolepsy, RLS

Medically Reviewed by Sabrina Felson, MD on July 17, 2023
9 min read

Do you struggle to stay awake during work and other activities and you don't know why? Could sleep apnea or another medical condition be the main culprit?

Sometimes the cause of sleepiness isn't easy to figure out. Here is information that can point you in the right direction and help you find the treatment that works best for you.

Sleepiness is likely a problem for you if:

  • You have trouble waking in the morning.
  • You often feel sleepy during your waking hours.
  • Naps don’t take the edge off your sleepiness.
  • You find yourself falling asleep in places you shouldn't like in a waiting room, a class, or even behind the wheel

Along with having to drag yourself through the day, you may also have:

  • Change or loss of appetite
  • Trouble with thinking or memory
  • Feelings of irritability or anxiety

About 20% of adults have sleepiness severe enough to affect their regular activities.

Not getting enough sleep -- sometimes by choice -- is the most common cause of excessive sleepiness. Working at night and sleeping during the day is another. Other causes include drug, alcohol, or cigarette use, lack of physical activity, obesity, and the use of certain medications.

But nodding off when you want or need to be awake may also be caused by an underlying condition. Depression or a sleep disorder -- such as restless legs syndrome, sleep apnea, or narcolepsy -- are common causes of problem sleepiness.

Restless legs syndrome (RLS) is a disorder characterized by unpleasant sensations in the legs and a strong urge to move them. RLS may also cause jerky leg movements every 20 to 30 seconds throughout the night. Sometimes RLS can affect other parts of the body, too.

RLS symptoms may occur or get worse while you’re at rest or sleeping. Because the symptoms are usually worse at night, they can greatly interrupt your sleep and lead to sleepiness when you need to be awake. RLS can be so bad, it is mistaken for insomnia.

Treatment for Restless Legs Syndrome

Moving your legs lessens RLS symptoms. These steps may also be enough to relieve symptoms of RLS:

  • Take iron or vitamin B12 or folate supplements if your doctor says your levels are low and recommends them.
  • Talk to your doctor about whether a medication or herbal remedy that you’re taking may be making symptoms worse. These could include medication that treats high blood pressure, nausea, colds, allergies, heart conditions, or depression.
  • Stay away from alcohol, caffeine, and nicotine.
  • Maintain a healthy diet, exercise regularly, and try relaxation techniques such as hot baths and massage.

If these steps are not enough, several types of medication are useful for treating the symptoms of restless legs syndrome or for inducing deep sleep. They include:

Because these drugs have not been compared thoroughly in studies, the best approach is to start with one and see how it works. If it’s ineffective, work with your doctor to find an alternative. In severe cases, a combination of drugs may work best.

Sleep apnea is becoming a more common cause of sleepiness in children and adults.

Sleep apnea occurs when the upper airway collapses for at least 10 seconds during sleep -- and does so up to hundreds of times each night. Obstructive sleep apnea is the result of a blockage in the airway. Central sleep apnea occurs when the brain fails to send signals to the muscles that control breathing.

Snoring and gasping for air as the airway reopens occur often with sleep apnea. But you may not be aware you have sleep apnea unless your bed partner tells you about the ruckus you’re making.

Because your breathing is interrupted, so is your sleep, leading to sleepiness during school, work, or other activities. You might mistake yourself as a “good sleeper” because you can sleep anytime, anywhere. But falling asleep in traffic or at work is obviously less than ideal. People with sleep apnea have many more auto accidents than people who don’t have the condition.

Sleep apnea can cause other problems, too: wide swings in heart rate as well as a decrease in oxygen levels. It is associated with and the possible cause of other medical conditions such as:

The most common treatments for sleep apnea include:

  • Continuous positive airway pressure (CPAP). In this treatment, a nasal device attached to a machine with a blower unit helps keep the airway open. CPAP is the most common treatment used for obstructive sleep apnea.
  • Inspire. This is a small impulse generator that is implanted beneath the clavicle and acts as a stimulator for your upper airway..
  • Solriamfetol (Sunosi). This medication can be used to improve wakefulness in people who have excessive sleepiness due to sleep apnea.
  • Oral appliance therapy. Devices move the tongue, lower jaw, or soft palate forward, which opens the airway.
  • Weight loss. If you have obesity, losing weight can decrease the risk for sleep apnea by reducing fat deposits in the neck. It also reduces many of the other risks associated with sleep apnea, such as heart disease.
  • Surgery. This may be an option if other treatments don’t work.

In addition to treatments for sleep apnea, it is important to manage other conditions, such as high blood pressure, that often exist along with it.

Narcolepsy is a sleep disorder that causes disabling daytime sleepiness and other symptoms. Narcolepsy is related to the dreaming period of sleep called REM (rapid eye movement) sleep. With narcolepsy, though, REM periods can occur throughout the day. In addition to drowsiness that doesn’t improve, narcolepsy may cause brief uncontrollable moments of sleep, or “sleep attacks,” without warning.

Another daytime hallmark of narcolepsy is sudden loss of muscle control, or cataplexy. This can be a slight feeling of weakness or total body collapse. It can last from seconds up to a minute. Cataplexy is related to the muscle immobility, or “paralysis,” that is part of REM sleep. It is often triggered by emotions or fatigue.

During sleep, narcolepsy may cause insomnia, vivid and often frightening dreams or hallucinations, and temporary paralysis. Hallucinations and paralysis may both occur during the process of falling asleep or waking up.

If you have narcolepsy, you may experience depression or other symptoms such as poor concentration, attention, or memory. These may be a result of intense fatigue and lack of energy resulting from good-quality sleep and daytime sleepiness.

Treatment for Narcolepsy

Your doctor may prescribe these medications:

  • Stimulants such as armodafinil (Nuvigil), dextroamphetamine (Adderall), methylphenidate (Desoxyn), or modafinil (Provigil) are most commonly used to help people stay awake.
  • Antidepressants such as tricyclics or serotonin reuptake inhibitors can help with cataplexy, hallucinations, and sleep paralysis.
  • Pitolisant (Wakix): It is unclear just how it works but it appears to act on the histamine receptors in the brain to help you stay awake.
  • Sodium oxybate (Xyrem), a central nervous system depressant, helps control cataplexy, when a person suddenly feels weak or collapses.
  • Solriamfetol (Sunosi), a dual-acting dopamine and norepinephrine reuptake inhibitor, helps patients stay awake longer.

Two or three naps during the day may improve daytime sleepiness from narcolepsy. A good diet and regular exercise may improve narcolepsy symptoms.

Feelings of sadness, anxiety, and hopelessness that persist are symptoms of depression. Other symptoms include problems with forgetfulness and concentration, as well as a loss of energy. Often, activities that were once pleasurable no longer are. Physical symptoms of depression may include back pain or stomach upset.

Depression is strongly related to sleep problems and sleepiness. It’s not always easy to tell whether depression causes sleep problems or sleep problems contribute to depression. In some cases, both may be the case. Sleep problems and depression may share risk factors and respond to the same treatment.

Several types of sleep disorders are linked to depression. These include insomnia, obstructive sleep apnea, and restless legs syndrome. People with insomnia may be 10 times more likely to have depression.

Treatment for Depression

These are some of the most effective treatments for depression:

  • Cognitive behavioral therapy (CBT). This involves targeting thoughts that lead to depressive feelings and changing behaviors that make depression worse.
  • Medications. These include antidepressants, and mood-stabilizing anticonvulsants or lithium for depression associated with bipolar disorder.
  • Exercise and diet changes. This includes limiting caffeine and alcohol.

Up to 35% of adults have insomnia, which is trouble getting to sleep or staying asleep. It can be temporary or long-lasting.

Things that can cause it or make it worse include:

  • Stress
  • An irregular sleep schedule
  • Caffeine, nicotine, alcohol, and some medications
  • Physical or mental illness
  • ADHD
  • Dementia
  • Other sleep disorders like apnea or restless legs syndrome

Treatments for insomnia include:

  • Improved sleep habits. You might go to sleep and get up at the same time each day; eliminate noise, light, and distraction in your bedroom; and avoid screen time, caffeine, and alcohol after a certain hour. 
  • Cognitive behavioral therapy (CBT). You get this from a trained psychologist, who works to replace your worries about sleep with healthier beliefs.
  • Medication. If better sleep habits and CBT don't work for insomnia, your doctor may prescribe drugs including benzodiazepines (tranquilizers), newer types of sedatives called nonbenzodiazepines or "Z drugs," melatonin agonists, or orexin receptor agonists. Bear in mind these medications are known for a high incidence of abuse.

Hypersomnia is what doctors call a variety of conditions in which you often feel overly tired or sleep too much. It can happen because of illnesses like epilepsy or Parkinson's disease, or mental conditions like depression. It's also the main symptom of narcolepsy and of a condition called Kleine-Levin syndrome. Certain medications, as well as alcohol and drug abuse, can cause it as well.

Sometimes, this excessive sleepiness has no known cause. That's called idiopathic hypersomnia.   

The FDA has approved calcium, magnesium, potassium, and sodium oxybates (Xywav) to treat IH in adults. It is believed to work through chemicals like dopamine and its brain pathways involved in wakefulness. It is not considered a stimulant. In addition, medications used for narcolepsy help many people with hypersomnia. Better sleep habits may make a difference, too.

Some other sleep disorders that may cause excessive sleepiness include:

  • Circadian rhythm sleep disorders, a group of conditions caused by problems with your body's internal "clock." This might cause you to fall asleep too late, wake up too early, or have a hard time adjusting to a sleep schedule. These conditions can be mild, like jetlag, or more serious.
  • Periodic limb movement disorder. In this rare illness, your legs and feet, and sometimes your arms, jerk or twitch as you sleep. You may not even be aware this is happening. It's not the same as restless legs syndrome, although some people have it along with RLS.

A sleep doctor can diagnose and treat these conditions. Depending on how serious your disorder is, they may treat it with lifestyle changes, medication, or both.

In addition to the steps above, try these strategies for excessive sleepiness:

  • Keep a consistent sleep schedule.
  • Do relaxing things at bedtime.
  • Use your bedroom only for sleep and sex.