Parasomnia is a group of sleep disorders that are caused by malfunctions in the central nervous system when asleep. They occur when a person is partially awake. The common parasomnias are sleepwalking, night terrors, sleep paralysis, and sleep hallucinations. Normally, one is not usually aware of most of these events and might have little to no memory of their occurrences after waking up.  Parasomnias are disruptive and make it difficult to maintain sleep throughout the night, thus causing insufficient sleep. The conditions mainly occur in children who gradually stop experiencing them as they grow up.

Types of parasomnias

The common types of parasomnias include:

1. Sleepwalking

Sleepwalking is a disorder in which an individual has unusual body movements when asleep. One can walk and engage in other activities while in their sleep without being aware. The condition occurs when the central nervous system (CNS) is over-excited during sleep. This fault leads to the person carrying out routine activities while still asleep. Some of the activities that can be carried out in sleepwalking include:

  • Walking
  • Sitting up in bed
  • Eating
  • Dressing
  • Driving

Some of the characteristics that indicate that a person is sleepwalking are:

  • A glazed expression
  • Strange and clumsy behavior
  • Unresponsiveness
  • Confusion after waking up
  • No memory of the event after waking up

2. Night terrors

Night terrors are terrifying experiences that occur when a person is asleep. These experiences are imagined but they appear real to the individual, thus causing significant panic reactions. They are characterized by:

  • Screaming
  • Increased body movement
  • Kicking
  • Restlessness
  • Increased heartbeat
  • Increased breathing
  • Sweating

3. Sleep paralysis

Sleep paralysis is an unpleasant experience that causes a person to feel immobilized when asleep. The individual is unable to move their limbs for a short time, and the paralysis causes significant distress. The condition occurs while one wakes up, thus the victim will be fully aware of the event and remembers it clearly after waking up. During the event, the person experiences:

  • Immobility
  • Difficulty in breathing
  • Panic reactions
  • Distress

4. Sleep-related hallucinations

These are hallucinations that occur during sleep causing one to experience imaginary sensations. The sensations appear real to the individual and are usually distressing. They occur when one is about to fall asleep or wake up and have a surreal appearance. The person is terrified and confused during the occurrence. The common sleep hallucinations are visual and consist of vivid images and light changes. During sleep hallucinations, the patient experiences:

  • Terror
  • Anxiety
  • Rapid breathing
  • Increased heart rate
  • Confusion after waking up
  • Mumbling during sleep
  • Restlessness


The symptoms of parasomnias are different depending on the type of condition that one experiences. However, the general symptoms that indicate that a person is experiencing parasomnias include:

1. Excessive daytime sleepiness

People that commonly experience parasomnia do not get sufficient sleep. The condition(s) disrupts night time sleep, thus causing one to feel sleepy during the day. One can doze off easily and might feel the urge to take frequent day time naps to make up for the lack of sleep. Excessive daytime sleepiness affects a person’s daily function by making it difficult to stay alert. Hence, it can be dangerous to people that perform activities that require high levels of concentration, such as operating heavy machinery.

2. Fatigue

Fatigue is a general feeling of tiredness. A fatigued person lacks the energy and motivation to carry out daily activities. Parasomnia disturbs sleep causing the individual to not get well-rested. The sleep quality and efficiency are lowered, thus one is not refreshed in the morning. People experiencing fatigue are easily irritated, weak, run out of breath easily, and have difficulty in making decisions.


Parasomnias occur due to alterations in the sleep states leading to faults in the transitions between wakefulness and sleepiness. The main causes of parasomnias are:

1. Complications in non-rapid eye movement sleep (NREM)

NREM is a stage of sleep that is regulated by higher brain centers and in which dreams are not experienced. During this stage, one transitions from sleep to wakefulness or from wakefulness into sleep. The sleep during this stage is light and the period lasts for a few minutes. The individual is not fully aware of their surroundings but is partially awake. If observed, the person will show both sleep and wake features. They might exhibit unusual behavior in sleep, such as increased body movement and restlessness, which is usually noticed by a sleep partner. Many parasomnias occur during NREM sleep, including sleep paralysis, sleepwalking and, night terrors.

2. Complications in rapid eye movement sleep (REM)

REM sleep is a normal sleep stage in which one experiences dreams.  Alterations in REM sleep cause a person to experience vivid dreams that appear real. When the central nervous system becomes over-excited during REM sleep, the individual can react to objects in their dreams. The person’s body movement increases and they engage in abnormal behavior, such as walking and talking during sleep.

3. Drug or substance abuse

Drug and substance abuse can alter one’s sleep states causing mental instability. The person, therefore, exhibits unusual and often undesirable behavior.  Intoxication impairs brain function and causes sleep fragmentation. This fragmentation affects the transition between wakefulness and sleepiness, thus triggering parasomnia. Illicit drugs are commonly associated with sleepwalking and sleep hallucinations. Withdrawal from illicit drugs also provokes unusual sleep behaviors.

4. Underlying medical condition

Parasomnia is commonly a sign of an underlying medical condition. Many people who exhibit unusual behavior when asleep have neurological or psychiatric conditions. These conditions affect the function of the brain and can lead to sleep fragmentation. Some of the health conditions that trigger parasomnia include:

  • Febrile illnesses
  • Schizophrenia
  • Parkinson’s disease
  • Stress
  • Melatonin deficiency
  • Anxiety
  • Depression
  • Post-traumatic sleep disorder

5. Under-development of the central nervous system (CNS)

CNS plays a significant role in controlling bodily functions. When the CNS is not fully developed, it can function erratically leading to unusual body activity. Parasomnia occurs when the CNS is excited during sleep causing movements when the body should be immobile. The condition is commonly seen in children and young adolescents and resolves with time when the CNS matures.

6. Some medications

Some medications are known to trigger parasomnias. They include:

  • Selective serotonin reuptake inhibitors
  • Tricyclic antidepressants
  • Beta-adrenergic blocking agents
  • Alzheimer’s disease medications

Many of these medications impact the brain and affect its ability to control muscle function. When this alteration occurs during REM sleep, the person reacts to non-existent objects that are only present in a dream. The victim will portray unusual behaviors, such as kicking, talking, walking, and screaming, when asleep.


Parasomnia is diagnosed based on the information available about the occurrence of the disorder. In many cases, the individual experiencing parasomnia has little to no memory of the condition, and therefore the information is provided by family, friends, or a sleep partner. Doctors can further probe one’s sleep habits to help confirm a case. Other than the information provided, there are several tools and techniques that doctors use in diagnosing parasomnia, including:

1. Medical history

An individual’s medical history can help the doctor to diagnose parasomnia. Neurological and psychiatric medical conditions commonly trigger parasomnia by affecting the function of the brain. A doctor will reviews the patient’s medical history to identify any conditions that affect sleep, such as PTSD, depression, schizophrenia, anxiety disorders, Parkinson’s disease, and febrile illnesses. In the case of children, the parents or guardians provide the information on the other underlying health conditions the young patient may have.

2. Electroencephalography (EEG)

An EEG test involves measuring a person’s brain waves when asleep and identifying any abnormalities. The EEG machine is used to record the brain activity through electrodes that are attached to one’s scalp when asleep. An individual who experiences parasomnia shows both sleep-like and wake-like features during sleep. This overlapping of the sleep states leads to the unusual behaviors that are exhibited when asleep, such as walking, mumbling, and kicking.

3. Sleep study

An overnight sleep study, commonly known as a polysomnography, is often carried out when diagnosing sleep disorders. The study involves examining one’s activity when asleep. Different elements of sleep are analyzed including breathing rates, heartbeat, muscle activity, and eye movements. This study is normally carried out in a sleep center where the individual is observed throughout the night by a doctor.

4. Physical and neurological exam

Doctors usually examine the individual’s present physical and neurological condition to identify sleep disorders. The test is done to rule out any other health conditions and neurologic disorders that can disrupt one’s sleep. A thorough physical examination is carried out by observing the different areas that are involved in sleep. If a complication is identified, further tests are carried out using computerized tomography (CT) and magnetic resonance imaging (MRI) scans.


There is no specific treatment for parasomnia because it is a large group of conditions each with different causes and triggers. It is, however, managed using different methods, including:

1. Medications

Medications can be used to manage parasomnia when the symptoms occur frequently. Some of the medications used in treatment include:

a. Benzodiazepines

Benzodiazepines are the most commonly used medications in the treatment of parasomnia. They are primarily used to prevent awakening in the middle of the night. When taken, they suppress the CNS and prevent its excitement when a person is asleep. Thus, they are highly effective in treating parasomnias caused by complications in REM sleep. There are many types of benzodiazepines available, including:

  • Clonazepam (Klonopin)
  • Alprazolam (Xanax)
  • Diazepam (Valium)
  • Clobazam (Onfi)
  • Lorazepam (Ativan)

b. Antidepressants

Antidepressants have a sedative effect and, therefore, suppress the CNS when they are taken. They prevent awakening during the night due to a faulty excitement of the CNS. Hence, one can sleep throughout the night without disturbances after taking them. Antidepressants improve sleep quality and efficiency, thus prevent the occurrence of parasomnia symptoms.

c.  Melatonin supplements

Melatonin is a hormone that regulates sleep and wake times. In absence of light, a large amount of melatonin is produced, thus enabling the person to fall asleep throughout the night. During the day, the production of melatonin reduces and the person stays alert. Melatonin supplements, which can be purchased over the counter, can be used to reduce the symptoms of parasomnia. They help one to get deep sleep without interruptions throughout the night. Also, these supplements come with no side effects for most people or at the least minimal, unlike other prescription drugs that have harsh and long term side effects.

2. Alternative medications

When parasomnia is triggered by the medications that one is taking, doctors usually recommend alternative medications or dosages. The alternative medication will reduce the symptoms of parasomnia while still treating one’s health condition. Some medications that frequently trigger parasomnia are antidepressants and treatments for Alzheimer’s disease.

Doctors can recommend a change from tricyclic antidepressants to selective serotonin reuptake inhibitors (SSRIs), which have fewer side effects. Some common SSRIs are fluoxetine (Prozac), sertraline (Zoloft), citalopram (Celexa) and escitalopram (Lexapro). Individuals who get parasomnias when using SSRIs can also use alternatives such as Bupropion (Wellbutrin), mirtazapine (Remeron), vilazodone (Viibryd), and vortioxetine (trintellix).

Cholinesterase inhibitors are normally used for Alzheimer’s disease and the common ones include Donepezil (Aricept), Galantamine (Razadyne), and rivastigimine (Exelon). A patient’s progress is usually closely monitored thus a doctor can recommend a change from one medication to another, when side effects are noticed. One of the alternative medicines is Memantine (Namenda), which regulates the activity of glutamate in the body.

3.     Cognitive-behavioral therapy

Cognitive-behavioral therapy involves educating the patient about the condition that they are going through. It aims at improving mental health by helping the individual think positively about the condition. Parasomnia leads to stress and anxiety as well as negative thoughts patterns about harming oneself and others. Through cognitive behavioral therapy, the negative thoughts are replaced or mitigated, and one is able to manage the condition better.

4. Physical safeguards

Parasomnia increases a person’s body movements when asleep. This increases the risk of harming oneself and others. The doctor can, therefore, recommend changing the sleeping environment to ensure that it is safe. This can be done by:

  • Removing potentially harmful objects from the room, such as sharp objects
  • Padding the floor around the bed
  • Adding barriers to the edges of the bed
  • Decluttering the bedroom


Parasomnia is a large group of sleep disorders that occur due to the malfunction of the CNS when asleep. They cause unusual and undesirable behaviors, such as walking, talking, kicking, and screaming, when asleep. A delay in the maturation of the CNS during childhood is the main cause of the condition. The under-developed CNS can err in its function, thus causing activities that occur in wakeful episodes to erroneously happen during sleep. Other factors that trigger parasomnia are dissociations in REM and NREM sleep states, drugs or substance abuse, underlying health conditions, and some prescription medications. There is no specific treatment for parasomnia but it can be managed by preventing the activation of the CNS during sleep. Medications, such as benzodiazepines, antidepressants, and melatonin supplements, enable one to maintain uninterrupted sleep throughout the night. Parasomnia can also be managed through cognitive therapy and changes in the sleep environment to keep the person and others safe.


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