The Big Picture
Delirium happens when a person suddenly becomes severely confused and their brain function changes quickly. The person may have trouble knowing where they are, paying attention, or staying alert. Their behaviour and awareness can change within a short time.
Delirium is often temporary. It usually happens because of a health problem or another cause that may be treated.
Delirium is always an emergency. If you notice sudden signs of delirium while caring for a client, you must tell your supervisor at once.
Look for Nova Scotia CCA Notes throughout this page for current provincial guidance.
Quick tip: Tap, click, or press Enter on any term with a dotted underline and an ⓘ icon to see its plain-English definition.
Start Here If You’re Overwhelmed
Focus on these core ideas:
- Delirium is severe confusion that begins suddenly and causes rapid changes in brain function.
- Delirium is often temporary and may disappear after its cause is treated.
- Possible causes include illness, medication reactions, dehydration, poor nutrition, emotional trauma, and major life changes.
- Signs can include changing alertness, difficulty concentrating, memory problems, unusual behaviour, and emotional changes.
- Report sudden signs of delirium to your supervisor at once. Delirium must always be treated as an emergency.
- Treatment focuses on finding and controlling or reversing the cause.
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Course Notes: Key Ideas You Need to Know
1. What Is Delirium?
Delirium is a condition involving sudden, severe disorientation and rapid changes in brain function.
Disorientation means mental confusion or difficulty recalling people, time, or places. It may result from changes in the brain, disease, substances, or a combination of these factors.
A person experiencing delirium may have sudden changes in:
- Attention and concentration
- Awareness and alertness
- Memory
- Speech and behaviour
- Movement
- Emotions and personality
Key fact: Delirium often lasts only temporarily. It may disappear when the illness or condition causing it is treated.
Delirium usually results from a physical or mental health disorder that can be treated. It does not always have the same cause.
2. What Causes Delirium?
Several physical, emotional, and life-related factors may cause delirium.
Physical and Health-Related Causes
Possible causes include:
- Medication reactions: A response to medication may cause delirium.
- Infection or other illness: A physical illness can lead to sudden confusion.
- Poor nutrition: Not receiving adequate nourishment may contribute to delirium.
- Food poisoning: This can be a cause of delirium.
- Dehydration: Not having enough fluid in the body may lead to delirium.
Emotional and Life-Related Causes
Delirium may also occur after emotional trauma or a major life change.
Examples include:
- Experiencing the death of a loved one
- Moving into a care facility
- Experiencing emotional trauma
These examples show that delirium is not limited to physical illness.
3. Signs and Symptoms of Delirium
One important feature of delirium is that a person’s mental state can change rapidly.
For example, a client might become drowsy, then agitated , and then drowsy again.
The signs and symptoms can affect attention, memory, awareness, movement, emotions, and behaviour.
Changes in Attention, Thinking, and Speech
A client experiencing delirium may have:
- Difficulty concentrating: The client struggles to keep their attention on something.
- Attention disturbance: The client has difficulty maintaining purposeful thinking or behaviour.
- Incoherent speech: The client’s speech becomes difficult to understand.
- Difficulty stopping speech patterns or behaviours: The client may be unable to stop certain patterns of speaking or acting.
These changes can appear suddenly.
Changes in Orientation, Memory, and Perception
Delirium can affect how a person understands their surroundings and remembers information.
Signs may include:
- Disorientation to time or place: The client is confused about when or where they are.
- Decreased short-term memory and recall: The client has trouble remembering recent information.
- Changes in sensation and perception: The client’s experience or understanding of what they sense changes, increasing confusion.
- Signs of illusions or hallucinations: These may occur as part of the changes in perception.
Changes in Awareness and Sleep
Delirium can affect how awake, alert, or aware a person appears.
Signs include:
- An altered level of consciousness or awareness
- Changes in normal sleep patterns
- Drowsiness
- Changes in alertness throughout the day
Important pattern: A client with delirium is usually more alert in the morning and less alert at night, when drowsiness may increase.
Alertness can also change quickly between different mental states.
Changes in Movement
Delirium may cause changes in motor activity.
Motor activity refers to movement. A client may show changes in how they move or in their activity level.
Emotional and Personality Changes
Delirium may cause changes in a client’s emotions or personality.
These changes can include anxiety, anger, depression, or irritability.
Two other terms have specific meanings:
- Apathy: A lack of emotional feeling that appears as indifference.
- Euphoria: An exaggerated or abnormal expression of physical or emotional well-being that does not reflect reality.
Key fact: Delirium may affect several areas of a person’s functioning at once. It is not limited to confusion about time or place.
4. Why Delirium Is an Emergency
Delirium must always be treated as an emergency.
Delirium is often the first or only sign of a physical disorder in older persons and people with dementia.
This means a serious physical disorder may first become noticeable through sudden confusion.
The cause must be identified, and delirium must be treated immediately.
In many cases, such as those involving stroke, symptoms can become permanent. Symptoms may also worsen and lead to death.
What the CCA Must Do
If you observe any sudden signs or symptoms of delirium in a client:
- Recognize that the sudden change may be delirium.
- Inform your supervisor at once.
Do not delay reporting sudden signs of delirium.
The cause needs to be determined, and the client needs immediate treatment.
Nova Scotia CCA Note
Sorrentino’s Canadian Textbook for the Support Worker, 5th Edition tells the CCA to report sudden signs of delirium to a supervisor at once. In Nova Scotia, current CCA standards explain how recognizing and reporting changes fits within the CCA role.
Nova Scotia CCAs use observational point of care assessment. This means observing a person’s condition before, during, and after care. It includes noticing changes in awareness, thinking, emotions, and physical condition. These observations help the CCA recognize when a change needs to be reported to a supervisor.
This is not a comprehensive nursing assessment. The CCA does not perform the detailed nursing evaluation used to make care-planning decisions. CCAs must follow their employer’s emergency procedures, including the interventions and reporting required within their role.
Why this matters in Nova Scotia: When a client suddenly becomes confused, the CCA recognizes the change and reports it immediately. The CCA follows workplace emergency procedures without taking on the nursing assessment role.
Official source: Continuing Care Assistant Occupational Standards of Practice
Last checked: October 10, 2026
5. How Delirium Is Diagnosed
A client with delirium should be examined by a physician as soon as possible.
The physician investigates what is causing the sudden change in brain function.
Tests That May Be Ordered
The physician will most likely order tests such as:
| Test | Information to Remember |
|---|---|
| Blood work | May include checking blood and alcohol levels. |
| EEG | A test that may be ordered during the investigation. |
| Computed tomography (CT) | A scan of the client’s head. |
| MRI | Another type of head scan that may be ordered. |
| Chest X-ray | An imaging test that may be ordered. |
| Lumbar puncture (spinal tap) | Another procedure that may be used to investigate the cause. |
The physician uses testing to help determine what is causing the delirium.
Key fact: A client with delirium is usually admitted to a hospital and treated as an inpatient.
An inpatient is someone who has been admitted to a hospital for care.
6. How Delirium Is Treated
The main goal of treatment is to control or reverse the cause of the symptoms.
Treatment depends on the specific condition responsible for the delirium.
Treating the Underlying Cause
Treatment may involve addressing:
- Medication use, including stopping certain medications
- Alcohol consumption, including stopping alcohol use
- Heart failure
- Decreased oxygen
- Psychiatric conditions, such as depression
- Other disorders contributing to disorientation
The exact treatment depends on what is causing the client’s symptoms.
Why it matters: Successful early treatment of medical and psychiatric disorders that occur together often greatly improves mental functioning.
Managing Dangerous or Agitated Behaviour
Some clients experiencing delirium may become aggressive or agitated. Their behaviour may put themselves or others in danger.
In these situations:
- Some clients may need medications to control aggressive, agitated, or dangerous behaviour.
- These medications are usually given in very low doses.
- Medication doses may be adjusted as needed.
- Some clients may need admission to a psychiatric facility, particularly when dangerous behaviour continues.
7. Understanding Delirium and Dementia
Delirium and dementia both involve changes in brain functioning, but they are not the same condition.
Dementia is a general term for a group of illnesses involving progressive loss of brain functions.
These changes can affect:
- Memory
- Behaviour
- Learning
- Communication
- Thinking and social functioning
Dementia may be classified as a mild or major neurocognitive disorder, depending on its symptoms.
Delirium Compared With Dementia
| Delirium | Dementia |
|---|---|
| Begins suddenly. | Involves progressive loss of brain functions. |
| Causes rapid changes in brain functioning. | Involves changes in cognitive and social functioning. |
| Is often temporary. | Describes a group of illnesses involving progressive loss. |
| May disappear when the cause is treated. | Involves changes in areas such as memory, behaviour, learning, and communication. |
Important: Delirium and dementia can exist together.
A client may have a chronic disorder causing dementia and also develop an acute disorder causing delirium.
A person who already has dementia can still experience sudden delirium. Sudden signs of delirium must be treated as an emergency.
Exam Clue Words
Certain words are especially important when reviewing delirium and the CCA’s response.
- Always: Delirium should always be treated as an emergency, even though it is often temporary.
- At once: Sudden signs and symptoms of delirium must be reported to your supervisor at once.
- Immediately: The cause of delirium needs to be determined, and delirium needs immediate treatment.
- As soon as possible: A client experiencing delirium should be seen by a physician without delay.
Common Mix-Ups
| Wrong Idea | Better Idea |
|---|---|
| Delirium develops gradually. | Delirium begins suddenly and involves rapid changes. |
| Delirium is always permanent. | Delirium is often temporary and may disappear after its cause is treated. |
| Delirium only happens because of physical illness. | Physical illness, medication reactions, emotional trauma, and major life changes may cause delirium. |
| Delirium only causes confusion. | Delirium can also affect memory, speech, movement, alertness, emotions, and behaviour. |
| A client with dementia cannot also have delirium. | Acute disorders causing delirium may exist alongside chronic disorders causing dementia. |
| Sudden confusion can wait because delirium is often temporary. | Delirium is always an emergency, and sudden signs must be reported at once. |
Fast Review
Use these points for a quick review before your exam. Focus on sudden changes, possible causes, important signs, and the need for immediate action.
- Delirium: Sudden, severe disorientation with rapid changes in brain function.
- Disorientation: Mental confusion or difficulty recalling people, time, or places.
- Causes: Medication reactions, infections, illness, poor nutrition, food poisoning, dehydration, emotional trauma, and major life changes.
- Mental state changes: A person may alternate rapidly between drowsiness and agitation.
- Thinking and memory signs: Difficulty concentrating, incoherent speech, confusion about time or place, and reduced short-term memory.
- Awareness and sleep signs: Changes in consciousness, drowsiness, altered sleep patterns, and changing alertness.
- Emotional changes: Anxiety, anger, apathy, depression, euphoria, and irritability may occur.
- Emergency response: Delirium must always be treated as an emergency. Report sudden signs to your supervisor at once.
- Diagnosis: A physician should assess the client as soon as possible and may order blood tests, EEG, head CT or MRI, chest X-ray, or lumbar puncture.
- Treatment: The goal is to control or reverse the cause. Treatment depends on the underlying condition.
- Dangerous behaviour: Some clients may need low-dose medications, adjustments to treatment, or psychiatric facility admission.
- Delirium versus dementia: Delirium begins suddenly and is often temporary. Dementia involves progressive loss of brain functions. Both can exist together.
Final Pep Talk
Delirium includes many different signs, so you do not need to memorize them all in one sitting. Start by reviewing what sudden changes look like, what may cause them, and why immediate reporting matters. Those connections will help you make sense of the details as you study.