Source of information about DSM diagnoses: American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.). American Psychiatric Publishing.

overview

The DSM-5 categorizes sleep-wake disorders for use by mental health and general medical clinicians across all age groups. It includes 10 major disorders: insomnia disorder, hypersomnolence disorder, narcolepsy, breathing-related sleep disorders, circadian rhythm sleep-wake disorders, NREM sleep arousal disorders, nightmare disorder, REM sleep behavior disorder, restless legs syndrome, and substance/medication-induced sleep disorder. Common to all are complaints about sleep quality, timing, and quantity, leading to daytime distress and impairment.

The DSM-5 aims to simplify differential diagnosis and referral decisions for sleep complaints, balancing clinical utility with scientific advances since DSM-IV. A “lumping” approach was used for some conditions (e.g., combining various insomnia types into one diagnosis with specifiers), while a “splitting” approach was applied for others (e.g., subdividing narcolepsy based on biological markers).

Compared to the more detailed ICSD-3 classification used by sleep specialists, the DSM-5 offers a broader, simpler framework designed for non-experts. This approach improves reliability and validity, with the DSM-5 linking its categories to their ICSD-3 counterparts. Advances such as the use of biological markers (e.g., hypocretin levels, polysomnography) are now integrated into the diagnosis of certain sleep disorders like narcolepsy, breathing-related disorders, and restless legs syndrome.

DSM Chapter Sections:

• Insomnia Disorder: Difficulty falling asleep, staying asleep, or waking too early with resulting daytime impairment.
•  Hypersomnolence Disorder: Excessive sleepiness despite adequate nighttime sleep, with prolonged sleep episodes or frequent daytime naps.
• Narcolepsy: Recurrent, sudden daytime sleep episodes, often accompanied by cataplexy, low hypocretin levels, or abnormal sleep studies.
• Breathing-Related Sleep Disorders: 

  • Obstructive Sleep Apnea Hypopnea

  • Central Sleep Apnea

  • Sleep-Related Hypoventilation

• Circadian Rhythm Sleep-Wake Disorders: Disorders involving misalignment between internal biological clocks and the external environment, causing insomnia or excessive sleepiness.
• Parasomnias: Abnormal behaviors or experiences during sleep or transitions between sleep and wakefulness. Includes:

• • Non-Rapid Eye Movement (NREM) Sleep Arousal Disorders

  • Nightmare Disorder

  • Rapid Eye Movement (REM) Sleep Behavior Disorder

•  Restless Legs Syndrome:  A sensorimotor sleep disorder characterized by an urge to move the legs, often accompanied by uncomfortable sensations.
• Substance/Medication-Induced Sleep Disorder: Sleep disturbances related to substance intoxication, withdrawal, or medication use.
• Other Specified Sleep-Wake Disorder: Symptoms of a sleep-wake disorder that cause distress or impairment but do not meet full criteria for any specific disorder, with a specified reason provided.
• Unspecified Sleep-Wake Disorder: Symptoms of a sleep-wake disorder that cause distress or impairment but do not meet full criteria for a specific disorder, and no specific reason is provided.

insomnia disorder

Insomnia disorder is characterized by dissatisfaction with the quantity or quality of sleep, accompanied by difficulty initiating or maintaining sleep. Individuals with this disorder experience significant distress or impairment in social, occupational, or other important areas of functioning. Insomnia can occur independently or alongside another mental disorder or medical condition. There are different patterns of insomnia, including sleep-onset insomnia (difficulty falling asleep), sleep maintenance insomnia (frequent awakenings during the night), and late insomnia (early-morning awakening with an inability to return to sleep). Often, individuals experience a combination of these symptoms, which may change over time. The diagnosis is largely based on subjective reports rather than objective sleep measurements, as individuals often perceive greater sleep difficulties than are shown through methods like polysomnography. Nonrestorative sleep, where sleep feels unrefreshing despite sufficient duration, may also occur, though it can be difficult to distinguish as an isolated issue. Daytime impairments related to insomnia include fatigue, decreased cognitive performance, mood disturbances, and general distress. Importantly, not all sleep disturbances meet the criteria for insomnia disorder; the defining factor is significant daytime impairment resulting from nighttime sleep difficulties.

Associated Features:

• Preoccupation with sleep, frustration about sleeplessness, and a cycle of hyperarousal that worsens sleep difficulties.

• Maladaptive behaviors and thoughts related to sleep, including irregular schedules, excessive time in bed, napping, fear of sleeplessness, and clock-watching.

• Sleep often improves in unfamiliar environments away from conditioned habits and routines.

• Daytime effects such as fatigue, low energy, irritability, anxiety, and somatic complaints like headaches or gastrointestinal discomfort.

• Mild depression, anxiety, worrisome thinking styles, and occasional cognitive impairments requiring increased effort for complex tasks.

Criteria:

A. There is a consistent concern about not getting enough sleep or not feeling well-rested, along with at least one of the following difficulties:

1. Difficulty falling asleep. In children, this may appear as needing caregiver assistance to fall asleep.
2. Difficulty staying asleep, with frequent awakenings or trouble getting back to sleep. In children, this may also require caregiver assistance.
3. Waking up too early in the morning and being unable to fall back asleep.

B. The sleep concerns leads to significant distress or problems in areas such as social, work, school, academic, or behavioral functioning.
C. The sleep problems occur at least three nights per week.
D. The sleep problems have lasted for at least three months.
E. The sleep problems happen even though the person has sufficient opportunity to sleep.
F. The insomnia is not better accounted for by another sleep-wake disorder, such as narcolepsy, sleep apnea, circadian rhythm disorders, or parasomnias.
G. The insomnia is not caused by the effects of a substance, such as medications or drugs.
H. Other mental health conditions or medical problems do not fully explain the sleep complaints.

Specify If:

• With a mental disorder (such as depression or substance use)

• With a medical condition (such as chronic pain)

• With another sleep disorder (such as restless legs syndrome)

• Episodic: Symptoms last at least one month but less than three months.

• Persistent: Symptoms continue for three months or longer.

• Recurrent: Two or more episodes occur within a one-year period.

hypersomnolence disorder

Hypersomnolence disorder is characterized by excessive sleepiness despite obtaining a seemingly sufficient or extended amount of sleep. Individuals may experience prolonged nighttime sleep, lengthy daytime naps, and a sense of sleep inertia, where they feel groggy, disoriented, and cognitively impaired upon waking. Sleep is typically of good quality and efficiency, with individuals falling asleep quickly, but they continue to feel excessively sleepy, particularly in sedentary settings such as during lectures, reading, or watching television. In more severe cases, unintentional sleep episodes can occur even during active or high-attention situations like meetings or social events. Some individuals may engage in automatic behaviors, completing tasks without memory of them, particularly during periods of extreme sleepiness. Sleep episodes can occasionally extend to 9 or more hours, and naps often exceed an hour without restoring alertness. Sleep inertia symptoms, including confusion and poor coordination upon awakening, are common and can last from several minutes to hours. Individuals often try to compensate for weekday sleep restrictions by sleeping longer on weekends or holidays, but despite these adjustments, they continue to experience nonrestorative sleep and significant daytime impairment.

Associated Features:

• Many individuals report that sleep feels nonrestorative, even after long sleep episodes.

• Naps tend to be prolonged, lasting over an hour, and often do not improve alertness.

• Short naps, when taken, are typically not refreshing.

• Individuals may appear noticeably sleepy in clinical settings, sometimes falling asleep while waiting.

• Some individuals have a family history of hypersomnolence disorder.

• Autonomic nervous system symptoms may occur, including vascular-type headaches, Raynaud’s phenomenon, and episodes of fainting.

Criteria:
A. The individual reports experiencing excessive daytime sleepiness despite having a main sleep period lasting at least seven hours, with at least one of the following:

1. Recurrent episodes of falling asleep or sudden lapses into sleep during the day.

2. Prolonged nighttime sleep lasting more than nine hours that is unrefreshing.

3. Difficulty achieving full wakefulness after abrupt awakening.

B. The symptoms occur at least three times per week and have persisted for at least three months.
C. The excessive sleepiness causes significant distress or impairment in important areas of functioning, such as cognitive, social, or occupational performance.
D. The symptoms are not better accounted for by another sleep disorder, such as narcolepsy, a breathing-related sleep disorder, a circadian rhythm disorder, or a parasomnia.
E. The excessive sleepiness is not due to the effects of a substance, such as medications or drugs of abuse.
F. The complaint of hypersomnolence is not fully explained by the presence of another mental or medical condition.

Specify if:

• With a mental disorder: Hypersomnolence occurs alongside a psychiatric condition, such as depression or a substance use disorder.

• With a medical condition: Hypersomnolence occurs with a medical issue, such as a neurological or endocrine disorder.

• With another sleep disorder: Hypersomnolence is present along with another diagnosed sleep disorder.

• Acute: Symptoms have lasted less than one month.

• Subacute: Symptoms have lasted between one and three months.

• Persistent: Symptoms have been present for longer than three months.

• Mild: Trouble staying alert during the day occurs 1–2 days per week.

• Moderate: Trouble staying alert happens 3–4 days per week.

• Severe: Trouble staying alert occurs 5–7 days per week, often significantly affecting daily activities.

narcolepsy

Narcolepsy is a chronic neurological disorder marked by repeated episodes of daytime sleepiness, naps, or sudden lapses into sleep that occur at least three times a week over a period of three months or more. Individuals may also experience one or more additional features: cataplexy (sudden loss of muscle tone triggered by emotions), low levels of hypocretin (a brain chemical that regulates wakefulness), or characteristic findings on specialized sleep studies. Daytime sleepiness is usually the first symptom and tends to worsen in quiet, sedentary settings, although brief naps can temporarily relieve sleepiness. Cataplexy involves brief, emotionally triggered episodes of muscle weakness without loss of consciousness, commonly affecting the face, neck, arms, legs, or entire body. In children or cases of rapid onset, cataplexy may present as persistent low muscle tone rather than sudden weakness. Diagnostic testing includes cerebrospinal fluid (CSF) analysis for hypocretin deficiency or sleep studies that show rapid onset of REM sleep. Sleepiness in narcolepsy may severely disrupt daily activities, and diagnosis often requires careful sleep history, sleep diaries, and ruling out other potential causes.

Associated Features:

• Automatic behaviors may occur during severe sleepiness, where individuals continue activities in a dazed, semiconscious state without memory of the actions.

• Vivid hallucinations may happen while falling asleep (hypnagogic) or waking up (hypnopompic), often involving visual, auditory, or tactile sensations.

• Episodes of sleep paralysis may leave individuals temporarily unable to move or speak upon awakening or falling asleep.

• Disrupted nighttime sleep is common, including frequent brief awakenings and intense dreams.

• Periodic limb movements and REM sleep behavior disorder may be present during sleep.

• Nocturnal eating and obesity are frequently seen in individuals with narcolepsy.

• During clinical observation, individuals may appear drowsy, fall asleep, or show physical signs of cataplexy such as slurred speech, drooping eyelids, or body collapse.

• Reflexes may be absent during cataplexy episodes, which helps differentiate genuine cataplexy from functional neurological symptoms.

• Cognitive challenges, including difficulties with working memory and executive functioning, have been reported despite normal IQ scores.

Criteria:

A. There are repeated episodes of an uncontrollable need to sleep, falling asleep suddenly, or taking naps during the same day. These events happen at least three times per week over a period of at least three months.

B. At least one of the following must be present:

1. Episodes of cataplexy, seen as either:
   a. In individuals with a long-standing diagnosis, brief episodes (lasting seconds to minutes) of sudden, bilateral muscle weakness triggered by laughter or joking, while maintaining consciousness.
   b. In children or those within six months of symptom onset, spontaneous grimacing, jaw-opening with tongue thrusting, or general loss of muscle tone without an emotional trigger.

2. Low hypocretin-1 levels in the cerebrospinal fluid, measured as either one-third or less of normal values, or less than or equal to 110 pg/mL. These levels must not be low due to other conditions like brain injury, inflammation, or infection.

3. Abnormal sleep study results, such as a nocturnal sleep study showing rapid eye movement (REM) sleep onset in 15 minutes or less, or a multiple sleep latency test showing an average sleep latency of eight minutes or less, along with at least two REM episodes starting at sleep onset.

Specify whether: 

• Narcolepsy with cataplexy or hypocretin deficiency (Type 1): Criterion B1 or B2 is met.

• Narcolepsy without cataplexy and without hypocretin deficiency (Type 2): Criterion B3 is met, but not B1 or B2.

• Narcolepsy due to a medical condition: Either with or without cataplexy and/or hypocretin deficiency; in these cases, the medical condition must be coded first.

Specify Current Severity:

• Mild: Naps needed only once or twice daily; mild sleep disruption; cataplexy is rare or infrequent.

• Moderate: Multiple naps needed daily; moderate disruption of nighttime sleep; cataplexy occurs daily or several times a week.

• Severe: Almost constant daytime sleepiness; severe disturbance of nighttime sleep with vivid dreams and excessive movement; frequent, drug-resistant cataplexy attacks.

Breathing-related sleep disorders

Breathing-related sleep disorders are a group of conditions marked by abnormal breathing patterns during sleep that result in disrupted sleep and significant daytime symptoms such as fatigue, sleepiness, or cognitive impairment. These disorders include obstructive sleep apnea hypopnea, central sleep apnea, and sleep-related hypoventilation. Each condition involves different underlying mechanisms: airway obstruction, instability in respiratory control, or insufficient ventilation, respectively. Breathing disturbances can lead to drops in blood oxygen levels, sleep fragmentation, and cardiovascular or cognitive complications over time. Diagnosis typically requires a sleep study (polysomnography), and early identification is important to prevent serious health consequences.

Obstructive Sleep Apnea Hypopnea

Obstructive sleep apnea hypopnea is the most common type of breathing-related sleep disorder, marked by repeated interruptions in breathing during sleep due to upper airway obstruction. Each episode, whether a complete apnea or partial hypopnea, typically lasts at least 10 seconds in adults and is often accompanied by drops in blood oxygen levels or brief awakenings. The core symptoms include loud snoring, gasping or choking during sleep, and excessive daytime sleepiness. Diagnosis is confirmed either by finding at least five breathing interruptions per hour of sleep along with sleep-related symptoms, or by finding 15 or more breathing interruptions per hour, even without symptoms. Sleep studies such as polysomnography or out-of-center sleep testing are necessary for diagnosis. In children, even one obstructive event per hour may be enough for diagnosis, with different breathing patterns seen compared to adults. Most cases go undiagnosed, so attention to risk factors such as obesity, upper airway crowding, and high blood pressure is important for early identification and treatment.

Associated Features:

• Frequent awakenings during the night can lead to symptoms of insomnia.

• Individuals often report morning headaches, dry mouth, heartburn, or frequent nighttime urination.

• Symptoms may include erectile dysfunction and reduced libido.

• Breathing difficulties while lying down are commonly reported.

• High blood pressure is seen in over 60% of individuals with this disorder.

• Arterial blood gas testing may be normal but can reveal hypoxemia or hypercapnia in some cases.

• Imaging may show narrowing of the upper airway.

• Cardiac evaluations may reveal impaired heart function or arrhythmias during sleep.

• Individuals with severe oxygen desaturation during sleep may have elevated hemoglobin or hematocrit levels.

Criteria:

A. Diagnosis requires either (1) or (2):

1. Evidence from a sleep study showing at least five obstructive apneas or hypopneas per hour of sleep, plus one or both of the following:
   a. Nocturnal breathing problems, such as loud snoring, snorting, gasping, or breathing pauses.
   b. Daytime symptoms such as excessive sleepiness, fatigue, or feeling unrefreshed after sleep, not better explained by another mental or medical condition.
2. Evidence from a sleep study showing 15 or more obstructive apneas and/or hypopneas per hour of sleep, regardless of whether symptoms are present.

Specify Current Severity:

• Mild: Fewer than 15 events per hour of sleep.

• Moderate: 15 to 30 events per hour.

• Severe: More than 30 events per hour.

Central Sleep Apnea

Central sleep apnea is a sleep disorder characterized by repeated pauses in breathing during sleep due to a lack of respiratory effort, rather than an obstruction of the airway. These breathing interruptions occur at least five times per hour, as confirmed by a sleep study. Central sleep apnea differs from obstructive sleep apnea by involving variability or instability in the brain’s control over breathing rather than a physical blockage. Common subtypes include idiopathic central sleep apnea, Cheyne-Stokes breathing associated with heart failure or stroke, and central sleep apnea related to opioid use. In some cases, individuals experience both central and obstructive events during sleep. Sleep fragmentation, excessive sleepiness, and awakenings with shortness of breath are frequently reported. Severity is measured by the frequency of breathing disturbances, the degree of oxygen desaturation, and the extent of sleep disruption.

Associated Features:

• Individuals may present with daytime sleepiness, fatigue, or insomnia.

• Complaints often include fragmented sleep and waking with shortness of breath.

• Some individuals may be asymptomatic and identified through sleep studies.

• Signs of heart failure, such as jugular venous distension, lung crackles, or lower extremity swelling, may be observed in cases with Cheyne-Stokes breathing.

• Co-occurring obstructive sleep apnea events, including snoring and sudden breathing pauses, may be present.

• Symptoms such as confusion, depression, and worsened sleep quality can occur, particularly when related to opioid use.

Criteria:

A. There is evidence from a sleep study showing five or more central apneas per hour of sleep.
B. The breathing disturbances are not better explained by another current sleep disorder.

Specify Type:

• Idiopathic Central Sleep Apnea: Repeated breathing pauses during sleep without upper airway obstruction, caused by instability in respiratory effort.

• Cheyne-Stokes Breathing: A pattern of cyclical breathing with gradual increases and decreases in breathing effort, leading to central apneas or hypopneas, often associated with heart failure, stroke, or renal disease.

• Central Sleep Apnea Comorbid with Opioid Use: Breathing control is impaired due to opioid effects on brainstem respiratory centers.

Specify Current Severity: Severity is based on how frequently breathing interruptions occur, how much oxygen levels drop during sleep, and how fragmented or disturbed sleep becomes.

Sleep-Related Hypoventilation

Sleep-related hypoventilation is a breathing disorder that occurs during sleep, characterized by reduced ventilation leading to elevated carbon dioxide (CO₂) levels in the blood. It can be diagnosed through polysomnography by detecting increased CO₂ or, if direct CO₂ measurement is not available, by observing persistently low oxygen saturation not related to apnea or hypopnea events. Hypoventilation can occur independently (idiopathic) but more often develops alongside medical conditions such as chronic obstructive pulmonary disease (COPD), neuromuscular diseases, chest wall disorders, obesity, or as a result of certain medications, especially opioids. Symptoms may include excessive daytime sleepiness, frequent awakenings, insomnia, morning headaches, and signs of organ impairment like pulmonary hypertension or right-sided heart failure. Severity is determined by the extent of oxygen and carbon dioxide abnormalities during sleep, and in more advanced cases, during wakefulness.

Associated Features:

• Individuals may report insomnia, daytime sleepiness, or frequent awakenings during the night.

• Morning headaches are common and may be related to overnight CO₂ buildup.

• Some individuals experience orthopnea (difficulty breathing when lying flat), especially if diaphragm weakness is present.

• Sleep studies may reveal shallow breathing episodes, and co-occurring obstructive or central sleep apnea.

• Physical consequences can include pulmonary hypertension, cor pulmonale (right-sided heart failure), polycythemia (elevated red blood cells), and neurocognitive dysfunction.

• As the disorder progresses, blood gas abnormalities may be detectable even during wakefulness.

• Features of the underlying medical condition, such as respiratory or musculoskeletal findings, may also be present.

Criteria:

A. Sleep study findings show episodes of reduced breathing during sleep associated with elevated carbon dioxide levels. If direct CO₂ measurements are not available, persistently low oxygen levels without apneas or hypopneas may suggest hypoventilation.
B. The breathing disturbance is not better explained by another sleep disorder.

Specify Type:

• Idiopathic Hypoventilation: Decreased breathing during sleep without a clear underlying cause.

• Congenital Central Alveolar Hypoventilation: A rare genetic condition present from birth causing shallow breathing or apnea during sleep.

• Comorbid Sleep-Related Hypoventilation: Associated with another medical condition, such as lung disease, neuromuscular disease, chest wall deformity, obesity, or medication use.

Specify Current Severity: Severity is determined by how severely oxygen and carbon dioxide levels are affected during sleep and by the presence of complications such as heart or brain dysfunction. Blood gas abnormalities present during wakefulness indicate more severe disease.

Circadian Rhythm Sleep-Wake Disorders

Circadian rhythm sleep-wake disorders involve persistent or recurring patterns of sleep disruption caused by a misalignment between an individual’s internal biological clock and the external environment or required schedule. This mismatch leads to difficulty falling asleep, staying asleep, or waking at socially expected times, often resulting in insomnia, excessive daytime sleepiness, or both. When allowed to sleep according to their natural rhythms, individuals often experience normal sleep quality and duration. The delayed sleep phase type is the most commonly recognized, marked by difficulty falling asleep and waking up at desired times. Common issues include challenges waking in the morning, extreme grogginess, and difficulties maintaining regular sleep-wake patterns due to environmental or social demands.

Associated Features:

• Individuals often have a history of mental health disorders or concurrent psychiatric conditions.

• Persistent trouble waking in the morning, often with confusion or prolonged grogginess.

• Risk of developing secondary insomnia due to maladaptive sleep behaviors and heightened arousal from repeated failed attempts to fall asleep earlier.

• Daily functioning, including academic, occupational, and social activities, may be severely impacted.

Criteria:

A. There is a continuing or repeated pattern of sleep disruption primarily caused by a shift or misalignment in the body’s internal clock or between the internal clock and required sleep-wake schedules due to environmental, social, or occupational demands.
B. The sleep disruption results in symptoms of excessive sleepiness, insomnia, or both.
C. The sleep disturbance causes significant distress or impairment in social, occupational, or other important areas of functioning.

Specify Type:

• Delayed Sleep Phase Type: Sleep and wake times are delayed by more than two hours compared to desired or expected times, causing trouble falling asleep and waking up early enough for daily responsibilities.

  • Specify if Familial: There is a family history of delayed sleep phase.

  • Specify if Overlapping with Non-24-Hour Sleep-Wake Type.

• Advanced Sleep Phase Type: Sleep and wake times occur much earlier than desired, with individuals falling asleep and waking up earlier than socially expected.

  • Specify if Familial: A family history of advanced sleep phase is present.

• Irregular Sleep-Wake Type: No consistent sleep-wake pattern; sleep and wake periods vary throughout a 24-hour period.

• Non-24-Hour Sleep-Wake Type: The sleep-wake cycle consistently shifts later each day, failing to align with the 24-hour light-dark cycle.

• Shift Work Type: Sleep disruption related to working hours that are outside the traditional daytime schedule, leading to insomnia and/or excessive sleepiness during wake periods.

• Unspecified Type: The sleep disturbance does not fit a specific subtype.

Specify If:

• Episodic: Symptoms last at least 1 month but less than 3 months.

• Persistent: Symptoms continue for 3 months or longer.

• Recurrent: Two or more episodes occur within a single year.

Parasomnias

Parasomnias are a group of sleep disorders marked by abnormal behaviors, emotions, perceptions, or physiological responses that occur during sleep, specific sleep stages, or transitions between sleep and wakefulness. The most common parasomnias include non-rapid eye movement (NREM) sleep arousal disorders and rapid eye movement (REM) sleep behavior disorder. Each condition has distinct clinical features, underlying mechanisms, and specific treatment considerations. Parasomnias can cause significant distress or danger due to complex behaviors occurring without full consciousness.

Key Highlights:

• Non-Rapid Eye Movement (NREM) Sleep Arousal Disorders: Episodes of incomplete awakening from sleep, often involving sleepwalking or sleep terrors, with little or no memory of the events.
• Nightmare Disorder: Repeated, vividly recalled nightmares involving threats to safety or survival, leading to distress and interrupted sleep.
• Rapid Eye Movement (REM) Sleep Behavior Disorder: Acting out dreams during REM sleep due to a loss of normal muscle paralysis, often involving complex or violent movements.

Non-Rapid Eye Movement (NREM) Sleep Arousal Disorders

NREM sleep arousal disorders involve repeated episodes of incomplete awakening from sleep, typically occurring during the first third of the night during slow-wave sleep. Individuals may exhibit sleepwalking or sleep terrors. During these episodes, individuals are partially awake but not fully responsive to their environment, often showing a blank stare and engaging in complex or fearful behaviors. Limited or no dream recall is typical, and individuals usually have amnesia for the events upon waking. The behaviors can range from simple movements like sitting up in bed to complex activities like walking, running, or even driving. The severity and impact are judged based on the risk of injury, disruption to others, and distress caused by the events.

Associated Features:

• Sleepwalking episodes may include simple behaviors like sitting up or complex actions like walking outside, eating, or inappropriate toileting.

• Individuals often have little or no memory of the episode upon waking.

• Injuries during episodes may go unnoticed due to reduced pain perception during sleep.

• Sleep-related eating disorder involves episodes of eating during sleep, sometimes involving inappropriate or nonfood items.

• Sexsomnia (sleep-related sexual behaviors) may occur, often without conscious awareness, and can lead to interpersonal or legal consequences.

• Sleep terror episodes are marked by sudden, intense fear with screaming, rapid breathing, racing heart, and an overwhelming urge to escape.

• Episodes typically last a few minutes but can occasionally be longer, especially in children.

• Multiple episodes can sometimes occur across a single night.

Criteria:

A. Repeated episodes of incomplete awakening from sleep, usually during the first third of the major sleep period, accompanied by either:

1. Sleepwalking: Getting out of bed and walking about, with a blank stare and minimal responsiveness. Waking the individual is difficult.

2. Sleep terrors: Sudden awakenings with screams or cries, intense fear, and signs of autonomic arousal (e.g., rapid breathing, heart racing, sweating).

B. Little or no dream imagery is recalled.
C. The individual has amnesia for the episode.
D. The episodes cause significant distress or impairment in social, occupational, or other important areas of functioning.
E. The episodes are not due to the effects of a substance (e.g., drugs or medication).
F. The episodes are not better explained by another mental or medical disorder.

Specify Whether:

• Sleepwalking Type

  • Specify if:

    • With sleep-related eating

    • With sleep-related sexual behavior (sexsomnia)

• Sleep Terror Type

Nightmare Disorder

Nightmare disorder is characterized by repeated occurrences of extended, vivid, and distressing dreams that usually involve threats to survival, safety, or personal integrity. These dreams typically arise during REM sleep, often in the second half of the night when dreaming is more intense. Upon awakening, individuals quickly become fully alert, but the emotional distress caused by the nightmares can linger and affect daytime functioning. Nightmares are usually well-remembered, detailed, and realistic, and they may contribute to sleep avoidance, insomnia, or significant distress if they are frequent. Nightmare disorder is distinct from REM sleep behavior disorder because individuals retain normal REM muscle atonia and do not physically act out their dreams.

Associated Features:

• Mild signs of autonomic arousal, such as sweating, rapid breathing, and elevated heart rate, may occur during nightmares.

• Nightmares typically involve no physical movements or vocalizations because REM sleep normally suppresses body movement.

• Emotional distress from nightmares may persist into wakefulness, making it difficult to return to sleep.

• Sleep-onset REM periods (hypnagogic nightmares) may occasionally occur, sometimes associated with sleep paralysis.

• Bad dreams that do not fully awaken the individual can also happen and are recalled later.

• Talking or brief body movements may occur at the end of a nightmare but are typically minor.

Criteria:

A. Repeated episodes of long, distressing, and clearly remembered dreams, usually involving attempts to escape threats to survival, safety, or integrity, and typically occurring during the second half of the night.
B. Upon waking from the dream, the individual quickly becomes oriented and alert.
C. The nightmares cause significant distress or impairment in social, occupational, or other important areas of functioning.
D. The symptoms are not due to the effects of a substance, such as medications or drugs.
E. The nightmares are not better explained by another mental disorder or medical condition.

Specify If: During sleep onset

Specify if related to:

• With mental disorder (including substance use disorders)

• With medical condition

• With another sleep disorder

Specify If:

• Acute: Nightmares present for 1 month or less

• Subacute: Nightmares present for more than 1 month but less than 6 months

• Persistent: Nightmares present for 6 months or longer

Specify Current Severity:

• Mild: Fewer than one episode per week

• Moderate: One or more episodes per week but not every night

• Severe: Nightmares occur nightly

Rapid-Eye Movement (REM) Sleep Behavior Disorder

Rapid eye movement (REM) sleep behavior disorder is characterized by repeated episodes of vocalizations or complex physical movements during REM sleep, often reflecting the content of vivid, action-filled, or violent dreams. These dream-enacting behaviors can range from talking and shouting to running, punching, or kicking, and they sometimes result in injuries to the individual or their bed partner. These episodes typically occur after 90 minutes of sleep, more commonly in the later part of the night. Upon awakening, individuals are usually alert and able to recall vivid dream content that matches the behavior observed. Diagnosis is confirmed by detecting REM sleep without atonia on a sleep study or by clinical history combined with a diagnosis of a known synucleinopathy, such as Parkinson’s disease. Severity is judged based on the nature and consequences of the behaviors rather than frequency alone.

Criteria:

A. Repeated episodes of arousal during sleep involving vocalizations and/or complex motor behaviors.
B. These behaviors arise during REM sleep, typically beginning more than 90 minutes after falling asleep, becoming more frequent in the second half of the sleep period, and rarely occurring during daytime naps.
C. Upon awakening after an episode, the individual is fully alert and oriented.
D. Either of the following must be present:

1. REM sleep without normal muscle atonia observed on polysomnography.
2. A suggestive history of REM sleep behavior disorder in the presence of a diagnosed synucleinopathy (e.g., Parkinson’s disease, multiple system atrophy).

E. The behaviors cause significant distress or impairment in social, occupational, or other important areas of functioning, such as injury to self or others.
F. The symptoms are not due to the effects of a substance, such as medication or drug use, or another medical condition.
G. Coexisting mental or medical conditions do not adequately explain the behaviors.

restless leg syndrome

Restless legs syndrome (RLS) is a neurological sleep disorder characterized by a strong urge to move the legs, often accompanied by uncomfortable sensations described as creeping, tingling, burning, or itching. These symptoms typically begin or worsen during periods of rest or inactivity and are partially or completely relieved by movement. The sensations are usually worse in the evening or at night, disrupting the ability to fall asleep or stay asleep and causing significant daytime sleepiness and distress. Although primarily self-reported, RLS symptoms must be distinguished from other causes of leg discomfort, such as cramps or positional pain. RLS can severely impact sleep quality and daily functioning if not managed properly.

Associated Features:

• Periodic leg movements during sleep (PLMS) are present in up to 90% of individuals with RLS.

• Periodic leg movements may also occur during quiet wakefulness.

• Difficulty falling asleep and staying asleep is common, leading to daytime sleepiness.

• Family history of RLS in first-degree relatives supports the diagnosis.

• Symptoms often improve initially with dopaminergic medications.

• Severe cases may no longer show symptom relief with movement.

Criteria:

A. An urge to move the legs, usually accompanied by unpleasant sensations, characterized by all of the following:

1. Symptoms start or worsen during periods of rest or inactivity.

2. Movement partially or completely relieves the urge and discomfort.

3. Symptoms are worse in the evening or at night compared to daytime, or occur only during evening or nighttime hours.

B. Symptoms occur at least three times per week and have been present for at least three months.
C. Symptoms cause significant distress or impairment in social, occupational, academic, or other important areas of functioning.
D. Symptoms are not better explained by another medical condition (e.g., arthritis, leg cramps) or behavioral habits (e.g., habitual foot tapping).
E. Symptoms are not due to the effects of a substance, such as medication side effects or drug use.

Substance/medication-induced sleep disorder

Substance/medication-induced sleep disorder is marked by a significant disturbance in sleep that arises during, shortly after, or following withdrawal from the use of a substance or medication known to impact sleep. The symptoms must cause clinically significant distress or impairment and cannot be better explained by an independent, pre-existing sleep disorder. Sleep problems may appear during intoxication (such as stimulant use), withdrawal (such as alcohol withdrawal), or after exposure to medications (such as antidepressants or corticosteroids). Accurate diagnosis relies on clinical history, physical examination, or laboratory evidence linking the sleep disturbance directly to substance or medication use.

Associated Features:

• Sleep disturbances may include insomnia, hypersomnia, or a disruption in sleep architecture.

• Sleep problems typically begin during intoxication, withdrawal, or shortly after substance/medication exposure.

• Symptoms may resolve with abstinence but can persist in some cases, especially if withdrawal is prolonged.

• It is critical to distinguish these disturbances from independent primary sleep disorders.

• Substances frequently associated with sleep disturbances include alcohol, caffeine, cannabis, opioids, stimulants, sedatives, and certain medications like antidepressants.

Criteria:

A. There is a significant and severe disturbance in sleep.
B. Evidence from clinical history, physical exam, or lab tests shows both of the following:

1. Sleep disturbance developed during or soon after substance intoxication, withdrawal, or exposure to a medication.

2. The substance or medication is known to cause sleep disturbances.

C. The sleep disturbance is not better explained by an independent, pre-existing sleep disorder.
D. The sleep problem does not occur only during a delirium episode.
E. The disturbance causes significant distress or impairment in social, occupational, or other important areas of functioning.

Specify Type:

• Insomnia type: Difficulty falling asleep, maintaining sleep, frequent awakenings, or feeling unrefreshed after sleep.

• Daytime sleepiness type: Predominant complaint of excessive sleepiness or fatigue during waking hours, sometimes with prolonged sleep.

• Parasomnia type: Abnormal behavioral events during sleep.

• Mixed type: Multiple sleep symptoms present without one clearly dominating.

Specify Timing:

• With onset during intoxication: Symptoms develop during substance intoxication.

• With onset during withdrawal: Symptoms develop during or soon after withdrawal from a substance.

• With onset after medication use: Symptoms emerge when starting, adjusting, or discontinuing a medication.

other specified insomnia disorder

Other specified insomnia disorder applies when an individual has significant sleep difficulties that cause distress or impairment but do not fully meet the criteria for insomnia disorder or any other specific sleep-wake disorder. This category allows clinicians to indicate why the full criteria are not met by specifying the nature of the sleep problem. Examples include short-term insomnia lasting less than three months or cases where the primary complaint is nonrestorative sleep without difficulty falling or staying asleep.

Examples of “other specified” presentations:

• Short-term insomnia disorder: Sleep problems have lasted less than three months.

• Restricted to nonrestorative sleep: The main complaint is waking up feeling unrefreshed, without difficulty falling asleep or staying asleep.

unspecified insomnia disorder

Unspecified insomnia disorder is used when an individual has symptoms characteristic of insomnia that cause significant distress or impairment but do not fully meet the criteria for insomnia disorder or another specific sleep-wake disorder. This diagnosis is chosen when the clinician either does not specify the reason that criteria are not fully met or when there is not enough information available to make a more precise diagnosis. It provides flexibility in situations like emergency settings or when assessment is incomplete.

Other specified hypersomnolence disorder

Other specified hypersomnolence disorder applies when an individual has symptoms characteristic of hypersomnolence that cause clinically significant distress or impairment but do not fully meet the diagnostic criteria for hypersomnolence disorder or any other specific sleep-wake disorder. This diagnosis is used when the clinician chooses to specify the particular reason the criteria are not met. An example is brief-duration hypersomnolence, as seen in conditions like Kleine-Levin syndrome.

unspecified hypersomnolence disorder

Unspecified hypersomnolence disorder applies when an individual experiences symptoms characteristic of hypersomnolence that cause significant distress or impairment but do not fully meet the diagnostic criteria for hypersomnolence disorder or any other specific sleep-wake disorder. This diagnosis is used when the clinician does not specify the reason the criteria are not fully met or when there is not enough information to make a more precise diagnosis, such as in emergency or initial evaluation settings.

Other Specified Sleep-Wake Disorder

Other specified sleep-wake disorder applies when an individual experiences symptoms characteristic of a sleep-wake disorder that cause clinically significant distress or impairment but do not fully meet criteria for any specific sleep-wake disorder and do not qualify for other specified insomnia or hypersomnolence disorder. This diagnosis is used when the clinician chooses to specify the particular reason the criteria are not fully met, such as repeated arousals during REM sleep without confirmatory sleep study findings or history of a synucleinopathy like Parkinson’s disease.

Unspecified Sleep-Wake Disorder

Unspecified sleep-wake disorder is used when an individual has symptoms characteristic of a sleep-wake disorder that cause significant distress or impairment but do not fully meet the criteria for any specific sleep-wake disorder and do not qualify for unspecified insomnia disorder or unspecified hypersomnolence disorder. This category is used when the clinician does not specify the reason the criteria are not met or when there is insufficient information to make a more specific diagnosis, such as in emergency or initial evaluation settings.

self-check

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