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Delirium Symptoms, Facts and General Information

Published: 2015-09-25 - Updated: 2021-07-28
Author: Thomas C. Weiss | Contact: Disabled World (
Peer-Reviewed Publication: N/A

Synopsis: General information and overview of delirium, a disturbance in mental abilities that results in reduced awareness and confused thinking. Delirium is a serious disturbance in mental abilities that results in reduced awareness and confused thinking. The beginning of delirium is often times quick, within a few days or even hours. The symptoms often fluctuate throughout the day and there might be periods where the affected person experiences no symptoms. The symptoms tend to worsen during the night when it is dark and things appear less familiar.


Main Digest

Delirium, or acute confusional state, is defined as an organically-caused decline from a previously attained baseline level of cognitive function. Delirium itself is not a disease, but rather a clinical syndrome (a set of symptoms). Delirium typically involves other cognitive deficits, changes in arousal (hyperactive, hypoactive, or mixed), perceptual deficits, altered sleep-wake cycle, and psychotic features such as hallucinations and delusions.

This article is from our digest of publications relating to The Human Brain that also includes:

Delirium is a serious disturbance in mental abilities that results in reduced awareness and confused thinking. The beginning of delirium is often times quick, within a few days or even hours. Delirium can often be traced to one or more contributing factors such as changes in a person's metabolic balance, severe or chronic medical illness, infection, medication, drug or alcohol withdrawal. Due to the fact that symptoms of delirium and dementia can be similar, input from family members or a caregiver can be important for a doctor to make an accurate diagnosis.

Symptoms of Delirium

The signs and symptoms of delirium usually start over a few days or even hours. The symptoms often fluctuate throughout the day and there might be periods where the affected person experiences no symptoms. The symptoms tend to worsen during the night when it is dark and things appear less familiar. Main signs and symptoms of delirium are presented below.

Emotional Disturbances:

A person with delirium may experience emotional disturbances which may appear as fear, anxiety, paranoia, depression, anger or irritability, or a sense of euphoria. The person may feel apathy, quick and unpredictable mood shifts, or personality changes.

Changes in Behavior:

A person with delirium may experience changes in their behavior, such as seeing things that do not exist, agitation, restlessness, combative behavior, moaning, calling out, or making other sounds. Older adults may be quiet, withdrawn, move slowly, appear lethargic, experience disturbed sleep, or a reversal of their night-day sleep-wake cycle.

Poor Thinking Skills:

A person with delirium may experience poor thinking skills or cognitive impairment. The cognitive impairment can appear as poor memory, especially of recent events, disorientation such as a lack of awareness of where the person is, as well as difficulties with recalling words or speaking. The person may ramble verbally, have difficulties with understanding speech, or trouble with writing or reading.

Reduced Awareness:

A person with delirium can experience a reduction in their awareness of their environment. The reduction in awareness may result in an inability to remain focused on a topic, or to switch topics. The person may get, 'stuck,' on an idea instead of responding to conversation or questions. They can be easily distracted by things that are not important, or be withdrawn with little to no activity, or little response to their environment.

Types of Delirium

Medical experts have identified three types of delirium; Hyperactive delirium, Hypoactive delirium and Mixed delirium. What follows are descriptions of these types of delirium.

Dementia and Delirium

Dementia and delirium might be especially hard to distinguish and a person may experience both. Delirium frequently occurs in people with dementia. Dementia is the progressive decline of memory and other thinking skills due to the gradual dysfunction and loss of brain cells. The most common cause of dementia is Alzheimer's disease. Some difference between the symptoms of dementia and delirium exist and include the following:

Causes of Delirium

Delirium occurs when the usual sending and receiving of signals in a person's brain become impaired. The impairment is most likely caused by a combination of factors that make the person's brain vulnerable and trigger a malfunction in brain activity. Delirium may have a single cause or more than one such as medication toxicity or a medical condition. At times, no cause may be identified. Potential causes of delirium include the following:

A number of medications, or combinations of drugs may trigger delirium. These types of medications/drugs include some types of the following:

Delirium Risk Factors

Any condition resulting in a hospital stay, particularly in intensive care or following surgery, increases a person's risk of delirium; as does being a resident in long-term care. Examples of additional conditions that increase the risk of delirium include the following:

Delirium Complications

Delirium might last only a few hours, or it may last as long as several weeks or even months. If issues contributing to delirium are addressed, the person's recovery time is often times shorter. The degree of a person's recovery depends to some extent on their health and mental status prior to the onset of delirium. People with dementia; for example, might experience a notable overall decline in thinking skills and memory. People in better health are more likely to fully recover.

People with other chronic, serious or terminal illnesses might not regain the levels of thinking skills or functioning they had prior to the onset of delirium. Delirium in seriously ill people is also more likely to lead to the following:

Delirium Tests and Diagnosis

A physician will diagnose delirium based upon a person's medical history. Tests to assess mental status and the identification of potential contributing factors also play into the doctor's assessment. An examination related to delirium might include the following:

Additional Potential Testing:

A doctor might order urine, blood and other diagnostic tests. Brain-imaging tests might be used when a diagnosis cannot be made using other information available.

Mental Status Assessment:

A doctor begins by assessing the person's attention, awareness and thinking. The assessment may be done informally through conversation, or with screenings and tests that assess the person's mental state, confusion, perception and memory.

Physical and Neurological Examinations:

A doctor performs a physical examination, checking for signs of health issues or an underlying form of disease. A neurological examination checking for balance, vision, reflexes and coordination may help if a stroke or another neurological disease is causing the person's delirium.

Delirium Treatment and Drugs

The first goal of treatment for delirium is to address any underlying causes or triggers. For example; by stopping use of a certain medication or by treating an infection. Treatment then concentrates on creating the best environment for healing the person's boy and calming their brain. Supportive care aims to prevent complications by:

Consult the person's doctor about minimizing or avoiding the use of medications that might trigger delirium. Certain medications may be needed in order to control pain that is causing delirium. Other types of medications that may help to calm a person who misinterprets the environment in a way that leads to severe paranoia, hallucinations or fear, confusion or severe agitation may be needed as well. The drugs might be needed when a person with delirium presents with certain behaviors, such as endangering the person or threatening the safety of others, or if the person with delirium prevents the performance of a medical examination or type of treatment. The medications are usually reduced in dosage, or even discontinued when the person's delirium resolves.

Author Credentials:

Thomas C. Weiss is a researcher and editor for Disabled World. Thomas attended college and university courses earning a Masters, Bachelors and two Associate degrees, as well as pursing Disability Studies. As a Nursing Assistant Thomas has assisted people from a variety of racial, religious, gender, class, and age groups by providing care for people with all forms of disabilities from Multiple Sclerosis to Parkinson's; para and quadriplegia to Spina Bifida.

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Cite This Page (APA): Thomas C. Weiss. (2015, September 25). Delirium Symptoms, Facts and General Information. Disabled World. Retrieved August 19, 2022 from

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