A sleep disorder is a condition that frequently impacts your ability to get enough quality sleep. Many of us occasionally experience difficulties sleeping. Usually it’s due to stress, travel, illness, or other temporary interruptions to your normal routine. However, if you regularly have problems getting to sleep at night, wake up feeling exhausted, or feel sleepy during the day, you may be suffering from a sleep disorder.

Sleep disorders cause more than just daytime sleepiness. They can take a serious toll on your mental and physical health, including your mood, energy, and ability to handle stress. Ignoring sleep problems and disorders can lead to weight gain, car accidents, impaired job performance, memory problems, and strained relationships. If you want to feel your best, stay healthy, and perform up to your potential, quality sleep is a necessity, not a luxury.

Frequently having trouble sleeping can be a frustrating and debilitating experience. You sleep badly at night, which leaves you feeling dead-tired in the morning and whatever energy you have quickly drains throughout the day. But then, no matter how exhausted you feel at night, you still have trouble sleeping. And so the cycle begins again. But you don’t have to live with a sleeping problem. There are many things you can do to identify the underlying causes of your sleep disorder and improve your sleep, health, and quality of life.

Types of common sleep disorders:


Insomnia is characterized by an inability to initiate or maintain sleep. It may also take the form of early morning awakening in which the individual awakens several hours early and is unable to resume sleeping. Difficulty initiating or maintaining sleep may often manifest itself as excessive daytime sleepiness, which characteristically results in functional impairment throughout the day. Before arriving at a diagnosis of primary insomnia, the healthcare provider will rule out other potential causes, such as other sleep disorders, side effects of medications, substance abuse, depression, or other previously undetected illness. Chronic psychophysiological insomnia (or “learned” or “conditioned” insomnia) may result from a stressor combined with fear of being unable to sleep. 

·  Sleep-onset insomnia occurs when people have difficulty falling asleep, even when they are tired.

·  Sleep maintenance insomnia refers to difficulty staying asleep during the night.

·  Mixed insomnia is a hybrid condition characterized by sleep-onset and sleep maintenance insomnia symptoms.

Sleep Apnea

Snoring may be more than just an annoying habit – it may be a sign of sleep apnea. Persons with sleep apnea characteristically make periodic gasping or “snorting” noises, during which their sleep is momentarily interrupted. Those with sleep apnea may also experience excessive daytime sleepiness, as their sleep is commonly interrupted and may not feel restorative. Treatment of sleep apnea is dependent on its cause. If other medical problems are present, such as congestive heart failure or nasal obstruction, sleep apnea may resolve with treatment of these conditions. Gentle air pressure administered during sleep (typically in the form of a nasal continuous positive airway pressure device) may also be effective in the treatment of sleep apnea.

Most sleep apnea cases fall into one of the following two categories.

·  Obstructive sleep apnea (OSA) is caused by a physical obstruction that blocks the upper airway. This obstruction may be attributed to large tonsils or adenoids, fluid buildup from advanced heart or kidney failure, or genetic syndromes that affect facial structure such as cleft palate. Obese people with fat deposits around their neck are also at higher risk of OSA, and back sleeping can lead to apnea episodes if the tongue falls back into the throat. For many patients, continuous positive air pressure (CPAP) therapy is the most effective treatment

·  Central sleep apnea (CSA) occurs when the brain stops sending signals to the muscles that control breathing, leading to choking episodes during the night. As with OSA, obesity is a common risk factor for CSA. The condition may also affect people who have experienced a stroke, brain infection, and other medical problems with the brain stem, as well as those who take narcotic painkillers and other sleep-inducing medications. CPAP therapy is often prescribed for CSA, though some patients find bi-level positive air pressure (BiPAP) therapy more effective.


Excessive daytime sleepiness (including episodes of irresistible sleepiness) combined with sudden muscle weakness are the hallmark signs of narcolepsy. The sudden muscle weakness seen in narcolepsy may be elicited by strong emotion or surprise. Episodes of narcolepsy have been described as “sleep attacks” and may occur in unusual circumstances, such as walking and other forms of physical activity. 

Over time, narcolepsy can also cause sleep-onset and sleep maintenance problems. The condition known as Narcolepsy Type 1 often includes cataplexy, or a sudden loss of muscle tone that causes people to fall or slump over as they nod off. Sleep attacks also occur with Narcolepsy Type 2, but cataplexy is not present.

Restless Legs Syndrome (RLS)

RLS is characterized by an unpleasant “creeping” sensation, often feeling like it is originating in the lower legs, but often associated with aches and pains throughout the legs. This often causes difficulty initiating sleep and is relieved by movement of the leg, such as walking or kicking. Abnormalities in the neurotransmitter dopamine have often been associated with RLS. 

Excessive Sleepiness

EDS is defined by feelings of intense grogginess during the day that can compel people to sleep at inopportune times. People who feel excessively groggy during the day may also be more prone to errors and accidents. A wide range of medical and psychological conditions can lead to EDS, such as diabetes, hypothyroidism, chronic pain, depression, and anxiety. Other causes include certain sleep disorders like sleep apnea and periodic limb movement disorder. 

Shift Work Disorder

Shift work disorder primarily affects people whose jobs require them to work late at night or early in the morning. Sleeping during the day and working at night can cause misalignment between a person’s body and the circadian rhythms that guide their sleep-wake schedule based on natural light and darkness cycles. People with this condition often feel excessively tired at work and struggle to get enough sleep during their allotted daytime rest period.


Parasomnias are a group of unusual sleep behaviors that can occur before falling sleep, during sleep, or in the time between sleep and wakefulness. These are more commonly found in children, but some adults may experience them as well. These include sleepwalking, bedwetting, night terrors, and more unique ones like exploding head syndrome. Parasomnias are broken down into three categories: NREM-related parasomnias, REM-related parasomnias, and other.

Parasomnia is a collective term for unusual behaviors that occur prior to sleep, while asleep, or during the transition period between sleep and waking. These behaviors can occur during different sleep cycle stages, as well. Parasomnias that are mostly isolated to the non-rapid eye movement (NREM) sleep stages include the following:

·  Obstructive sleep apnea: Obstructive sleep apnea (OSA) is characterized by disordered breathing episodes, or apneas, during sleep. People with this condition will often wake up choking or gasping for air multiple times during the night, and report feelings of fatigue and non-restorative sleep during the day. OSA occurs when the airway is blocked due to certain physiological factors, such as a narrow throat, large tongue, smaller lower jaw, or obesity. Children may experience OSA if they have not had their tonsils or adenoids removed.

·  Central sleep apnea: Much like OSA, central sleep apnea, or CSA, causes apnea breathing episodes during the night. The key difference is root cause. CSA occurs when the brain stops sending signals to muscles that regulate breathing, rather than a physical obstruction blocking the airway. Strokes and other medical conditions that affect the brain stem can cause CSA, as can obesity, heart failure, and some medications.

·  Sleep-related hypoventilation disorders: These disorders occur when sleepers do not receive enough ventilation, causing the carbon dioxide levels in their blood to spike. Obesity, genetic abnormalities, certain drugs and medications, and underlying medical conditions can all lead to sleep-related hypoventilation.

·  Sleep-related hypoxemia disorder: Hypoxemia refers to below-normal blood oxygen levels. For people with this condition, their blood oxygen levels decrease primarily during sleep. Sleep-related hypoxemia may be a symptom of an underlying medical condition such as pulmonary hypertension, chest wall disorders, or neurologic and neuromuscular disorders.


Non 24-Hour Sleep Wake Disorder

For most adults, the circadian rhythms that guide their sleep-wake cycle and other bodily processes will reset every 24 hours. The condition known as non 24-hours sleep wake disorder occurs when someone’s circadian cycle exceeds the 24-hour mark. These individuals often experience delays of one to two hours in their sleep-onset and waking times. This disorder primarily affects those who are totally blind and people with dementia.


Lastly, some parasomnias are not isolated to the NREM or REM stages. They may also occur during the transition between sleep and wakefulness

·  REM sleep behavior disorder: Known as RSBD or RBD for short, REM sleep behavior disorder causes sleepers to physically or vocally act out on their dreams. The behaviors associated with this disorder can disrupt sleep for the individual and their partner, and also put people at higher risk of physical injury.

·  Sleep paralysis: Sleep paralysis causes people to feel completely paralyzed as soon as they wake up. This may also occur during sleep onset. Paralysis episodes usually don’t last for more than a few minutes, but this condition can trigger sleep anxiety for some people.

·  Nightmare disorder: While isolated nightmares are common for most people, nightmare disorder is defined by vivid, unpleasant dreams that disrupt sleep on a recurrent basis. For some, the nightmares become increasingly disturbing. People with nightmare disorder often experience anxiety about going to bed, as well as post-awakening anxiety when the dream ends.


Other parasomnias occur during the rapid-eye movement (REM) stage of the sleep cycle, when dreams are most likely to occur. These include:

·  Confusional arousals: Those who experience confusional arousals will exhibit confused behavior in bed due to an incomplete arousal from deep sleep. They won’t react to other people who attempt to intervene, and they’ll have little to no memory of the event.

·  Sleepwalking: Also known as somnambulism, sleepwalking occurs when people get out of bed and move about while still asleep. Sleepwalkers may remain in their bedrooms, but some travel to other areas in or outside of their residence. Attempting to wake up a sleepwalker can result in aggressive behavior.

·  Night terrors: When someone experiences night terrors, they often cry or act out in their sleep but will have little to no memory of the incident after waking. Most night terror episodes are brief, but they can last for several minutes in some cases.

·  Sleep-related sexual abnormal behaviors: People with this condition will display aggressive or uncharacteristic sexual behavior while asleep. As with other parasomnias, those with this condition – also known as “sexsomnia” – will remember very little, if any, of their behavior when they wake up

Idiopathic Hypersomnia: This condition, like narcolepsy, is characterized by the strong urge to fall asleep or lapses into sleep despite an otherwise healthy sleep schedule. However, idiopathic hypersomnia does not include cataplexy. To qualify for a diagnosis, patients cannot have any sleep disorders or preexisting conditions that explain the hypersomnia.

Kleine-Levin Syndrome: This rare disorder is defined by episodes of excessive sleep – up to 20 hours a day in some cases. The first episode often occurs in tandem with a bodily infection or excessive alcohol intake, and will usually occur every year or so. Episodes can persist for days, weeks, or even months. Common effects of Kleine-Levin Syndrome include cognitive dysfunction, altered perceptions, eating disorders, and disinhibited behaviors. Over the course of eight to 12 years, episodes of excessive sleepiness decrease in intensity and frequency.


Hypersomnolence refers to feelings of sleepiness and fatigue during the day despite a healthy circadian rhythm and an adequate amount of sleep the previous night. These feelings may lead to involuntary lapses into drowsiness or sleep, which in turn puts people at risk for accidents. Some people with hypersomnolence disorders feel the effects of daytime sleepiness before nodding off, while others will unknowingly fall asleep.

Jet lag disorder: This temporary disorder occurs when travelers pass through multiple time zones during a single flight or series of successive flights, leaving their circadian rhythm out of sync with local time at their final destination. The severity of jet lag depends on the length of travel, as well as the direction – eastbound travelers tend to experience stronger jet lag than those heading west.

Periodic limb movements disorder: People with this disorder – PLMS for short – will experience periodic bodily movements during the night that coincide with arousal and sleep disruptions. In most cases, movements are isolated to the lower limbs. Patients are often unaware of the movements or the sleep arousal.

Sleep-related bruxism: Sleep-related bruxism causes people to grind their teeth during sleep. Over time, this can cause excessive jaw pain, abnormal tooth wear, and other side effects. Many people with bruxism treat their condition with an anti-snoring mouthpiece or mouthguard, such as a mandibular advancement device that physically moves the jaw forward or a tongue retaining device that holds the tongue in place.