Subdural hematoma

A subdural hematoma is when blood collects on the surface of the brain underneath the skull. They are most commonly a result from a head injury and are caused when a vein ruptures between the surface of the brain and the skull. When blood pools, it presses on the brain, leading to increased risks of permanent damage. While the initial cause of the subdural hematoma may be classified as traumatic, any injury to the brain from the pressure of the subdural hematoma would be a non-traumatic injury.

There are two kinds of subdural hematomas: acute and chronic. Acute subdural hematomas are caused by severe head injuries – for example from a car accident. They form quickly and symptoms appear immediately. Acute subdural hematomas and the related medical issues are life-threatening. Chronic subdural hematomas are smaller and more common with mild head injuries or repeated injuries – for example, from a fall. They can also occur without any obvious connection to an injury. They are easier to treat, but they can have fatal complications.

Symptoms of a subdural hematoma

Symptoms of a subdural hematoma will appear right away in acute cases and gradually (or not at all) in chronic cases. Common symptoms include:

  • Confusion
  • Drowsiness
  • Headaches
  • Loss of consciousness
  • Nausea, vomiting
  • Numbness
  • Seizures
  • Slurred speech
  • Vision problems

These symptoms are similar to other serious medical issues like cardiac arrest or stroke. If you or someone else is experiencing symptoms, seek immediate medical attention.

Diagnosis and treatment for subdural hematoma

Doctors will perform tests to first confirm a person has a subdural hematoma. These tests will include computed tomography (CT) scans and MRIs. If there is a subdural hematoma, it will require surgery. There are a couple different surgery options available, and doctors will make recommendations based on how quickly they need to act to drain the blood from the brain’s surface. Doctors will explain the procedures and accompanying risks, as well as what they recommend as your best option. After your surgery, you will be kept in the hospital for recovery until you are evaluated and able to be discharged.

The effects of a subdural hematoma

A subdural hematoma can have lasting effects on your behaviour, cognition, and physical abilities, depending on where it was and the severity of the damage. There is also a chance that complications such as seizures may occur. You will need to work with a medical team to develop a rehabilitation and recovery plan to address any changes.

See sources


Stroke is a brain injury caused when blood flow to the brain is suddenly interrupted due to a clot or a ruptured blood vessel. The interrupted blood flow causes damage to the brain. Stroke can happen at any age and may result in the loss of the ability to move, to communicate, to process information, to swallow, to cope with stress, and more. Its after-effects often include extreme fatigue, depression, anxiety, deficits with memory, attention and vision, and the inability to sense self-movement and body position. Deficits depend on where and how much damage has occurred in the brain.

That is why, at the first signs of stroke (listed below), it is essential to call 9-1-1 and seek immediate medical attention to limit or, in some cases, reverse damage.

Topics in this section include:

Types of stroke leading to brain injury

About 85 per cent of strokes are ischemic, caused by a clot that blocks blood flow to the brain, and the remainder are hemorrhagic, caused when a weakened blood vessel bursts. A brain scan at the hospital will quickly determine the type and location of the stroke and the emergency treatment required.

Both kinds of stroke have similar symptoms, including drooping face, slurred speech, weakness, numbness, dizziness, confusion, and sudden severe headache. (See FAST, below)

Acute treatments are different, depending on the type and location of the stroke, which is why calling 9-1-1 and seeking immediate medical attention is critical. For both types of strokes, the patient will have a rehabilitation and treatment plan to follow when they leave the hospital.

People can also have a fleeting stroke called a Transient Ischemic Attack, or TIA. It is sometimes called a mini-stroke. TIA symptoms may only last for a few minutes, and usually less than a hour, and normally result in no lasting injury to the brain. However, a TIA is a warning sign that a more serious stroke may occur soon and medical care is required right away by calling 9-1-1.

Identifying a stroke using FAST

The key to minimizing the damage a stroke can do to the brain is getting medical attention as quickly as possible. The Heart and Stroke Foundation advocates using the FAST method to identify strokes in others (or in some cases, yourself). FAST stands for Face, Arms, Speech, and Time.

  • Face – is it drooping?
  • Arms – can both be raised?
  • Speech – is it slurred
  • Time – call 9-1-1 immediately

These are the main symptoms of stroke. Additional symptoms can include confusion, loss of consciousness, sudden and severe headaches, and nausea/vomiting.

Effects of stroke

A stroke causes damage to the brain, which can result in a variety of physical, emotional and cognitive effects that change the ability to move, communicate and process information. These effects can include:

  • Attention and memory deficits
  • Balance challenges
  • Bowel and bladder problems
  • Emotional challenges, like depression
  • Low energy
  • Muscle weakness
  • Paralysis – this can be localized (face, arm, or leg)
    • Hemiplegia (paralysis on one side of the body)
    • Quadriplegia (paralysis of all four limbs and trunk)
  • Sensation changes
  • Speech problems
  • Swallowing problems (dysphagia) 
  • Vision problems

These changes can make it difficult to prepare food, drive, work, or complete leisure activities.

Stroke and brain injury rehabilitation

In the first few days, doctors will be trying to stabilize you and make a medical diagnosis. Then recovery begins. The first stages of recovery can take different lengths of time for different people. You may feel tired and experience weakness. The medical team will work with you until you’re able to move to rehabilitation and be discharged from the acute care or stroke ward of the hospital.

Rehabilitation will vary depending on your needs, but the goals remain the same: to recover or adapt your abilities as best as possible. It will include physical, mental and cognitive exercises. It may also include working with a speech language pathologist (SLP) on speaking and swallowing. Occupational therapists (OT) can help with activities of daily living (ADLs), motor skills and home environments, and physical therapists (PT) can assist with muscle strengthening and range of motion (ROM) exercises. Rehabilitation takes a lot of time, practice and patience but it will help you regain independence by relearning or adapting your abilities.

Risk factors for a stroke

There are several lifestyle and conditional factors that can increase a person’s risk of stroke.

Lifestyle changes can improve your overall health while reducing risk of stroke. Conditional factors such as blood pressure and diabetes can be addressed with doctors, medications, and in some cases lifestyle adjustments.

Resources & Research

See sources

Hypoxia & anoxia

Hypoxia is when the body or brain is partially deprived of oxygen, leading to permanent damage. Anoxia is often a result of hypoxia where the brain or body completely loses its oxygen supply. Total loss of oxygen to the brain can result in severe permanent damage.

Hypoxia and anoxia can affect all major organs, including the brain and heart. There are three main types of hypoxia:

  1. Anemic – this means a reduced ability for blood to carry oxygen, so less oxygen is distributed to the body
  2. Stagnant – this means blood flow is reduced or restricted
  3. Histotoxic – this means that tissues in the body aren’t able to properly use the oxygen delivered by the blood

There is also something called hypoxemia. Hypoxia and hypoxemia sound similar, but refer to two different conditions. Hypoxia is when the body tissues aren’t getting the oxygen they need. Hypoxemia is when there is a lack of oxygen in the arterial blood.[1]

Causes of hypoxia and anoxia

Causes of hypoxia – which can lead to anoxia – include:

  • Breathing problems that affect oxygen supply, like asthma or pneumonia
  • Carbon monoxide or other toxins in the body
  • Cardiac arrest or stroke
  • Events that restrict air, like choking or near-drowning
  • High altitudes where oxygen is low
  • Significant blood loss

Symptoms of hypoxia and anoxia

In the situations where oxygen loss is more immediate – like choking or cardiac issues – symptoms will show up quickly. In other cases, like high-altitude climbing or breathing problems, they may appear more gradually.

Mild symptoms of hypoxia and anoxia include:

  • Difficulty concentrating
  • Difficulty moving your body
  • Dizziness
  • Memory trouble
  • Slurred speech
  • Unexpected or strange headaches

More severe symptoms include:

  • Hallucinations
  • Loss of consciousness
  • Seizures

Diagnosis and treatment for hypoxia and anoxia

Diagnosis of hypoxia or anoxia is done based on symptoms, recent activity and hospital tests. These tests could include blood work, CT or MRI scans, or an electroencephalogram (EEG). The most important step is to increase the supply of oxygen in the most appropriate way based on the findings of the medical team. Once stabilized, tests will be done to determine if there is any brain damage that could cause cognitive, behavioural or mobility changes. These effects will vary case by case depending on the location and the severity of the injury. Rehabilitation and ongoing medical treatment may be necessary.[2]


See sources


Meningitis is the inflammation of the membranes around the brain and spinal cord due to infection. There are two main strains of meningitis – viral and bacterial.  Viral meningitis is the most common and is rarely fatal. Individuals usually recover in 5-10 days. There are over 80 types of viral meningitis on this list. Bacterial meningitis is extremely serious – if not caught and treated within a few hours it can lead to death. There are over 50 types of bacterial meningitis on this list.

Meningitis commonly spreads through close contact, including coughing and sneezing. There are some vaccines that help prevent meningitis, but they don’t protect from all possible causes. People with compromised immune systems because of cancer treatment, HIV, infection, or other auto-immune diseases are more susceptible and need to be extra-cautious.

Please note: this page is written for adults, but meningitis often occurs in infants and children. Symptoms for this age group can get worse quickly, so it is important to monitor any symptoms your child is experiencing.

Symptoms of meningitis

Early symptoms (in first 6 hours) of meningitis include:

  • Fever
  • Headache
  • Irritability
  • Nausea/vomiting

Later symptoms of meningitis (6-12 hours) include:

  • Drowsiness
  • Leg pain
  • Muscle aches
  • Pale skin

After 12 hours, symptoms could include:

  • Cold hands and feet
  • Confusion
  • A decrease in responsiveness
  • Neck pain or a stiff neck
  • A rash (common for meningococcal disease)

While these symptoms are common with other conditions, if they appear suddenly, you should seek medical attention as soon as possible.

Diagnosis and treatment of meningitis

Meningitis is most often diagnosed through an analysis of spinal fluid. Spinal fluid is collected through a lumbar puncture: a needle is used to retrieve the fluid from around the spine. Depending on the doctor’s findings, meningitis is commonly treated through antibiotics. If you have a serious case of meningitis, you may have to stay under observation at the hospital.

The effects of meningitis

Meningitis has varying effects on people. Some fully recover with no lasting effects: in other cases, meningitis causes damage to the brain that will impact behaviour, cognition, and physical abilities. This can include memory loss, headaches, speech problems, hand-eye coordination problems, and changes in sight.

See sources

Cerebral edema

A cerebral edema (also known as increased intracranial pressure or ICP) is when brain tissue swells. This happens when there’s injury, an infection, after a stroke or because of a lack of oxygen (also called ischemia). When the brain swells, water collects in the tissues and pushes against the skull. This is an inflammatory response, and it happens because the body is trying to get more blood to the injured area. In the case of the brain, this puts pressure on the tissue which leads to damage. Cerebral edema can be life-threatening if the swelling isn’t managed quickly.

Causes of cerebral edema

Cerebral edema can be caused by brain tumours and cancers that move to the brain. It can also happen as a reaction to chemotherapy, brain bleeding, an infection in the brain, or if cerebrospinal fluid (CSF) is blocked.

Symptoms of cerebral edema

Symptoms of cerebral edema/brain swelling include:

  • Behaviour changes
  • Coordination problems
  • Dizziness
  • Headache
  • Loss of consciousness
  • Memory loss
  • Nausea
  • Restlessness
  • Vision problems
  • Vomiting
  • Weakness or numbness

If pressure increases on the brain tissue, a person may experience:

  • High blood pressure
  • Slow pulse rate
  • Unusual breathing patterns

Doctors will perform physical examinations and use computed tomography (CT) scans or MRIs to determine if you are experiencing a cerebral edema and find the cause.

Treatment for cerebral edema

After a doctor confirms a diagnosis of cerebral edema, they will prescribe treatment. This could include medication or surgery. Medication may be used to help reduce the brain swelling. They may also be used if the cause of the cerebral edema is an infection, or to treat symptoms associated with the cerebral edema.

Surgery may be recommended if CSF needs to be drained. This is the same process for someone with hydrocephalus, another condition that can cause brain injury. For more information about the surgical process of draining CSF, visit the hydrocephalus page.

See sources


Encephalitis (en-ceph-a-li-tis) is inflammation of the brain. It’s an uncommon non-traumatic brain injury, but can cause severe damage or even death.

Causes of encephalitis include bacteria, parasites (such as ticks), and viral infections. There are several different strains of encephalitis, often stemming from the different viruses (for example, the West Nile virus).

Symptoms of encephalitis

Symptoms of encephalitis include:

  • Confusion
  • Drowsiness
  • Fever
  • Headaches
  • Light sensitivity
  • Nausea
  • Stiffness in the neck

More serious symptoms include seizures, tremors and hallucinations.

Encephalitis vs. meningitis

The symptoms of encephalitis are similar to those of meningitis. That’s because both are inflammation in the brain. Inflammation of the membranes that surround the brain and spinal cord (called meninges) is meningitis, while encephalitis is inflammation of the brain tissue.

When to seek medical attention

Many of the symptoms for encephalitis overlap with more mild conditions, such as flu. But you should seek medical attention if the symptoms – particularly fever and confusion – appear suddenly without no clear cause.

Diagnosis of encephalitis

Doctors will use MRI or CT scans, electroencephalograms (EEG), or blood and spinal fluid tests to determine whether or not you have encephalitis.

Treatment of encephalitis

Treatment of encephalitis is dependent on the root cause and consultation with a medical team. Antiviral or antibiotic medications may be recommended to help reduce swelling and manage symptoms. Encephalitis can cause damage to the brain which can result in cognitive, behavioural, or physical changes – for example, trouble with memory, coordination or muscle weakness. Depending on the severity of damage to the brain, further treatment and rehabilitation may be needed.

See sources

Brain tumour

A brain tumour is an abnormal growth of cells within or around the structure of the brain. They can impact all areas of the brain and change how a person thinks, feels, and reacts. There are over 120 types of brain tumours, ranging from non-malignant (non-cancerous) to malignant (harmful or cancerous). In some cases, brain tumours can put pressure on surrounding tissue, leading to long-term effects.

It is unknown what causes brain tumours, yet family history, age, environmental exposure may be risk factors.

Signs and symptoms of brain tumour

Brain tumour symptoms vary from person to person and may appear overtime or all at once. Not every type of brain tumour will generate the same symptoms. The symptoms may also occur with other conditions, so may not indicate a brain tumour.

Common symptoms of a brain tumour include:

  • Behavioural changes
  • Cognitive changes
  • Dizziness or unsteadiness
  • Double or blurred vision
  • Frequent headaches
  • Hearing impairment
  • Morning nausea and vomiting
  • Seizures
  • Weakness or paralysis

Symptoms of a brain tumour will depend on the size and location of the tumour, and not everyone will experience all the symptoms listed.

A brain tumour is diagnosed by using a combination of neurological exams, magnetic resonance imaging (MRI) and computed tomography (CT) scans.

Treatment for brain tumour

Doctors will determine the best treatment for a brain tumour based on factors like:

  • Age
  • Overall health
  • Tumour location
  • Tumour size
  • Tumour type

For malignant tumours (such as cancer), surgery, radiation, chemotherapy, and immunotherapy are the most recommended treatments. For more information about cancerous tumours, including metastatic cancer, visit the Brain Tumour Foundation of Canada website.

In cases where surgery is not possible or the brain tumour is not doing any harm or causing any major symptoms, , doctors may recommend monitoring the tumour before making additional treatment decisions; this is called a “wait and see approach”. It’s important to discuss your available treatment options with the healthcare professionals about treatment.

Brain tumour recurrence

Sometimes a brain tumour can become ‘active’ again. This could indicate growth or change in the tumour. Normally this is discovered during routine checkups. If your tumour does come back or become active again, your healthcare team will determine the best course of treatment.

Tips for living with brain tumour

Ask for help & access support
You may need help from family, friends, or caregivers to complete activities of daily living (ADLs), get to appointments, or to run errands. But unless you ask, your circle of supporters may not know how best to help you. If there is something you need, you should always ask.

There are many ways to access support, whether that is one-on-one support, or attend a virtual brain tumour support group. Gain peer support in a safe, relaxed atmosphere from the comfort of your home.

Ask questions of your healthcare team
Your healthcare team has a wealth of knowledge about brain tumours, and they can help you learn all you can about yours. They can also keep you informed of treatment options and clinical trials for which you may be eligible.
Find ways to cope with cognitive, behavioural, and physical effects
The brain tumour may be altering your cognitive, behavioural, and physical abilities. This affects your activities of daily living (ADLs) and can mean that you can’t do things the same way you used to before your brain tumour.

There are ways to cope with those changes. For example, if you are experiencing memory problems, writing things down can help you keep track of tasks.

Learn about finding your new normal
With a brain tumour diagnosis comes a lot of change in your life. Nothing may ever be quite the same again. It will take time to adjust to your new normal, and you will experience strong emotions – even grief.

Learning what to expect when things are changing for you is a good way to pick up coping methods that can make transitions easier.

Take care of your physical health
A brain tumour is a health condition that can have many effects on mind and body. Eating a healthy balanced diet, exercising safely, and getting appropriate rest are great ways to take care of yourself.


Brain Tumour Foundation of Canada offers many programs, services, and support for anyone affected by a brain tumour. Their handbooks provide information about treatment options, long-term effects, and an overview of brain tumours. These handbooks are available in English and French (print copy shipped free in Canada or available electronically)

Adult Brain Tumour Handbook
Adult Brain Tumour Patient Handbook cover image

Order handbook

Non-Malignant Brain Tumour
Non-Malignant Brain Tumour Patient Handbook cover image

Order handbook

Pediatric Brain Tumour
Pediatric Brain Tumour Patient Handbook cover image

Order handbook

Brain Tumour Caregiver Handbook
Caregiver Brain Tumour Handbook cover image

Order handbook

See sources

Disclaimer: There is no shortage of web-based online medical diagnostic tools, self-help or support groups, or sites that make unsubstantiated claims around diagnosis, treatment and recovery. Please note these sources may not be evidence-based, regulated or moderated properly and it is encouraged individuals seek advice and recommendations regarding diagnosis, treatment and symptom management from a regulated healthcare professional such as a physician or nurse practitioner. Individuals should be cautioned about sites that make any of the following statements or claims that:

  • The product or service promises a quick fix
  • Sound too good to be true
  • Are dramatic or sweeping and are not supported by reputable medical and scientific organizations.
  • Use of terminology such as “research is currently underway” or “preliminary research results” which indicate there is no current research.
  • The results or recommendations of product or treatment are based on a single or small number of case studies and has not been peer-reviewed by external experts
  • Use of testimonials from celebrities or previous clients/patients that are anecdotal and not evidence-based 

Always proceed with caution and with the advice of your medical team. 


Hydrocephalus occurs when excess cerebrospinal fluid (CSF) builds up in the brain. Too much CSF causes the ventricles of the brain to expand, increasing pressure and causing damage.

Hydrocephalus can be congenital or acquired. Congenital hydrocephalus happens in the womb from conditions such as spina bifida (when the spine doesn’t properly form) or a brain malformation such as Aqueductal Stenosis, Arachnoid cysts, Porencephaly, and Dandy-Walker syndrome.

Acquired hydrocephalus can occur at any age. It can be caused by stroke, brain tumour, meningitis, intracranial bleeding, head injury, and other unknown (idiopathic) causes. While there are treatments available to help manage hydrocephalus, there is no permanent cure. This page is specifically for individuals with acquired hydrocephalus.


Symptoms of acquired hydrocephalus include:

  • Chronic headaches* that may not be relieved by pain medication
  • Cognitive challenges or changes in cognitive performance
  • Decline in academic or work performance
  • Difficulty waking up from sleep
  • Incontinence
  • Irritability/ personality changes
  • Loss of consciousness, fainting
  • Loss of coordination, motor performance, or balance problems, including gait disturbances: clumsiness, difficulty walking on uneven surfaces and stairs
  • Seizures
  • Tiredness or difficulty staying awake
  • Visual problems; blurred or double vision
  • Vomiting/nausea (especially projectile in children)

In diagnosing Normal Pressure Hydrocephalus, doctors look for a telltale triad of symptoms occurring together along with increases in the size of the ventricles in the brain: mild cognitive impairment, gait disturbances, and urinary incontinence.

*Headaches experienced by children and adults are often at the front of the head on both sides. They are generally severe upon waking or following a nap and may be relieved by sitting up. 

Diagnosis and treatment of hydrocephalus

Hydrocephalus is most often diagnosed through computed tomography (CT) or magnetic resonance imaging (MRI) scans, neurological examinations, lumbar punctures, and other tests. Once a diagnosis of hydrocephalus has been made, there are two options for treatment. When hydrocephalus needs to be treated, the person will either have surgery to create a small hole in the third ventricle in the brain to restore CSF flow (endoscopic third ventricle (ETV) surgery) or a surgery to implant a shunt in the ventricle that is experiencing the excessive CSF. These treatments help divert the excess CSF away from the brain. There are several different types of shunts available, and the neuro team will make recommendations based on your specific condition.

Since implanting the shunt is brain surgery, a neurosurgeon will be performing the procedure and be a part of creating the after-surgery care plan. It will involve a period of close-monitoring and a lot of rest mixed with appropriate activity. Maintaining and managing hydrocephalus and shunts will be a long-time process: doctors will be on the lookout for infections and malfunctioning shunts.

Effects of hydrocephalus

Hydrocephalus in adults can be caused by a brain injury and it can cause some of the same effects as brain injury. The shunt placement can also lead to some effects such as headaches or nausea.

Not everyone will experience the same effects, but they can include:

  • Attention and memory deficits
  • Auditory changes
  • Confusion
  • Constipation
  • Fine motor skill challenges
  • Muscle weakness and spasticity to mild imbalance
  • Seizures
  • Sensitivity to external pressures (for example weather)
  • Vision changes

These can be challenging to cope with, but with friends, family, and support services, you can learn to manage changes in your abilities.

Rehabilitation after hydrocephalus

Along with ongoing medical checkups to make sure treatment is progressing safely, you will most likely need to undergo rehabilitation for any physical, mental, or cognitive changes to your abilities.

Work with a neuropsychologist
A neuropsychologist can tell you how the brain controls abilities, and what effect hydrocephalus and brain injury can have on you. They will predict your progress over the short and long-term. This will be an ongoing process as conditions change.
Work with additional rehabilitation specialists
Occupational therapists, physical therapists, and cognitive behavioural therapists are all specialists that can help with independent living, adapting abilities, and learning.

Hydrocephalus in seniors

Hydrocephalus can develop in older adults and is called adult-onset hydrocephalus. The causes of hydrocephalus at this age are like causes for all ages (stroke, head injury, intracranial bleeding, meningitis, etc.) While many instances of hydrocephalus come with high intracranial pressure, adults over the age of 60 may develop a form called normal pressure hydrocephalus.

Normal pressure hydrocephalus (NPH)

Normal pressure hydrocephalus (NPH) occurs when the ventricles in the brain become enlarged with CSF, but there is no increase in intracranial pressure. Because of this, it’s often mistakenly diagnosed as early dementia, Parkinson’s or Alzheimer’s because it shares the same effects. The diagnosis is confirmed with computed tomography (CT) or magnetic resonance imaging (MRI) scans and treated the same way as any other form of hydrocephalus – by waiting and watching, surgically implanting a shunt or performing an ETV.

Resources and research

See sources

Disclaimer: There is no shortage of web-based online medical diagnostic tools, self-help or support groups, or sites that make unsubstantiated claims around diagnosis, treatment and recovery. Please note these sources may not be evidence-based, regulated or moderated properly and it is encouraged for individuals to seek advice and recommendations regarding diagnosis, treatment, and symptom management from a regulated healthcare professional such as a physician or nurse practitioner. Individuals should be cautioned about sites that make any of the following statements or claims that:

  • The product or service promises a quick fix
  • Sound too good to be true
  • Are dramatic or sweeping and are not supported by reputable medical and scientific organizations.
  • Use of terminology such as “research is currently underway” or “preliminary research results” which indicate there is no current research.
  • The results or recommendations of a product or treatment are based on a single or small number of case studies and has not been peer-reviewed by external experts
  • Use of testimonials from celebrities or previous clients/patients that are anecdotal and not evidence-based 

Always proceed with caution and with the advice of your medical team. 

Opioid overdose

Opioid overdoses can have catastrophic results, including brain injury. Brain injuries present new challenges and changes that can be difficult to cope with, particularly if the survivor is also trying to cope with substance use. It takes a long time to figure out the extent of the changes they have experienced and establish a continuing care plan that will help them with rehabilitation and the recovery process. The effects of the brain injury will change them as well. It’s a scary experience that can be hard to put into words or share with others and can have a huge impact on mental health and wellbeing.

This can feel incredibly lonely, but it’s important to remember that there are people and places that can provide support. Whether this is a family member, a friend, a support worker or even a local brain injury association , there are resources available to help a survivor succeed in their next steps.

Topics in this section include:

What are opioids?

Opioids are a drug used to manage pain, typically after surgery. They induce feelings of euphoria (happiness or ‘feeling high’). When prescribed by a doctor and taken in the recommended dosages, opioids can be safe. These prescriptions are often made with codeine, fentanyl, morphine, oxycodone, hydromorphone, or medical heroin.

Opioids can also be produced and obtained illegally and in a variety of forms. When obtained on the black market, opioid production is not controlled. Often these opioids contain unsafe doses of fentanyl or carfentanil. Carfentanil is specifically for large animals (like elephants), not humans. It’s approximately 100 times more toxic than fentanyl and 10,000 times more toxic than morphine. The smallest amount could cause an overdose.

How do opioid overdoses cause a brain injury?

An opioid overdose can cause damaging effects such as slowing breathing/heart rate and starving the brain of oxygen. The parts of the brain that use the most energy and oxygen are the most vulnerable. When loss of oxygen is more severe it can also damage areas of the brain that are fed by the smallest blood vessels that are furthest from the heart.  The medical term for partial oxygen deprivation is hypoxia. Hypoxia can worsen into anoxia when a person completely stops breathing.

Opioids have their effect by causing the brain to release dopamine, the brain’s natural opioid, in greater amounts. When used over a long period of time, the brain adapts by reducing the number of receptors, a process known as tolerance. Opioids alter the brain and how a person responds to normal rewards in the environment. Things that would normally make someone feel good and happy may no longer be motivating. That is why some people may, use drugs in a dangerous way, even though they know their opioid use is causing problems. This leads to a greater risk of overdose. Approximately 12 people die from opioid overdoses in Canada every day, having the biggest impact on Canadians aged 15-24 [1].

Currently there isn’t much research on individuals who acquire a brain injury through an opioid overdose. What is evident is that those who do survive an overdose from opioids can be left with catastrophic brain injuries that deeply affect the survivor and those close to them.

Substance use can continue to be a concern after a brain injury. The difficulties with attention, memory and judgment may make it more difficult to benefit from care. Substance use after brain injury can often interfere with the brain’s natural recovery and participation in treatment.

Effects of an opioid overdose

Depending on what parts of the brain are damaged and how long the brain was without oxygen, the survivor may experience [2]:

  • Limb weakness
  • Balance and coordination issues
  • Spasticity or rigidity in muscle tone
  • Abnormal, involuntary movements
  • Loss of vision
  • Memory loss
  • Speech and language challenges
  • Changes in cognitive abilities related to thinking and decision-making – this can affect future planning, work and social interactions
  • Changes in personality – this includes irritability, impulsiveness, and social impairments

The impact of overdose can range from subtle to severe. Some people may notice that they are more forgetful, less coordinated or have more trouble getting and staying organized. For survivors of many episodes of overdose, or longer and more severe anoxia, they may experience fundamental changes to their personality and abilities. Recovery does occur, but many changes may be lasting and require rehabilitation.

If you have had an opioid overdose and are experiencing subtle challenges, see the section below on ways to find help after an opioid overdose and brain injury

Substance use rehabilitation and brain injury

One of the existing challenges with treatment for substance use and brain injury at the same time is that current facilities/programs are not equipped to handle both. The majority of brain injury rehabilitation, community, and support programs require participants to be sober. Similarly, centres and programs that specialize in addiction support are not able to handle the complex needs of someone with a brain injury.

This does not mean that a support plan can’t be created – it just means that the survivor will need to work with caregivers and medical professionals with knowledge of what services are available.

See sources

Non-Traumatic Brain Injury (nTBI)

An acquired brain injury (ABI) refers to any damage to the brain that occurs after birth and is not related to a congenital or a degenerative disease. There are two types of acquired brain injury: non-traumatic and traumatic.

Topics in this section include:

Non-traumatic brain injury

Non-traumatic acquired brain injuries are caused by something that happens inside the body, or a substance introduced into the body that damages brain tissues.

This includes:

A video on acquired brain injury

Acquired brain injury affects every part of a person’s life. This includes changes to your independence, abilities, work, and relationships with family, friends, and caregivers. Since a brain injury differs from person to person and recovery depends on several factors, in many cases it’s difficult to know what long-term behavioural, cognitive, physical or emotional effects there will be.

The effects of brain injury can be put in the following categories [1]:

Behavioural changes: The way a person acts or makes decisions can change after a brain injury. Behavioural changes include engaging in risky or impulsive behaviour, having difficulty with social and work relationships and isolation. This can be stressful and depending on the behaviour can cause safety concerns. Rehabilitation and medical teams will be able to provide practical tips for behaviour after a brain injury.

Cognitive changes: This is how the brain learns, processes information, forms memories and makes decisions. Challenges include communication, concentration, reading/writing, making decisions, and remembering things.

Emotional changes: after a brain injury, a person may experience new or different emotions, including depression, anxiety, and/or anger. Emotional changes are difficult to adjust to, and it’s important to have a support system of family, friends, and medical professionals.

Physical changes: In some cases, a brain injury will have physical effects. These effects include mobility challenges, headaches, fatigue, pain and sensory changes.

Is a concussion a brain injury?

A concussion is an acquired brain injury. Anyone who sustains a concussion can experience many of the physical, cognitive, emotional, and behavioural effects that accompany acquired brain injuries.

Concussion is also known as mild traumatic brain injury (mTBI) that has no neuroimaging findings. The term mild does not diminish the impacts that concussion can have on your health and activities of daily living (ADLs).

The challenges of prognosis

Prognosis means the likely path a disease or injury will take. In the case of acquired brain injury, prognosis is meant to give a best estimate of effects and recovery. Acquired brain injuries are all different, and there are a lot of factors that will impact a prognosis of recovery.

Factors that affect prognosis include:

  • Severity of injury
  • Previous injuries and existing conditions
  • Access to treatment
  • Age
  • Location of injury

Research shows that there is no system or set of variables that can accurately predict outcome for a single patient [2]. There is no definite timeline for recovery – it’s different for everyone. Doctors will update their prognosis as recovery progresses and provide next steps at the same time.

This section of our website covers the kinds of changes you may experience, management tips, and information on the kinds of tools and services that can help you and your family navigate living with brain injury.


See sources