Evidence based

CBD and Brain Damage: How Does It Help With Traumatic Brain Injury (TBI)?

Recent research has shown promising results of cannabidiol (CBD) as an effective treatment for a wide range of symptoms due to traumatic brain injury.

Article By
Jodi Allen , last updated on October 17, 2020

Traumatic brain injury (TBI) affects over 69 million people around the world each year [1].

Survivors of traumatic brain injuries face a range of long-term difficulties including physical impairment, cognitive difficulties, personality changes, and mental illness, not to mention the emotional stress endured during recovery.

Unfortunately, most treatments and medications are ineffective and come with a host of unwanted side effects.

This is where CBD may be able to help. There’s evidence it can alleviate a wide range of health conditions related to TBI — such as epileptic seizures, anxiety, sleep disorders and inflammation of the brain.

Here, we discuss TBI and the potential role of CBD in managing recovery and improving quality of life. 


    Carlos G. Aguirre, M.D., Pediatric Neurologist

    Updated on October 17, 2020

  • Table of Contents

What is Traumatic Brain Injury (TBI)?

TBI usually occurs as a result of a violent blow or jolt to the head or body, caused by an external force.

Causes commonly include:

  • Car accidents
  • Falls
  • Physical assault
  • Being struck by an object during sport
  • Fights

TBI can be incredibly complex — the injury severity, location, type, individual’s age, and gender, all make up a unique brain picture, with no two TBI’s the same.

TBI can range from mild to severe — the latter resulting in permanent brain damage that can lead to lifelong disability. Outcomes of brain injuries vary between individuals — often leading to more than just the physical impairments, but also significant behavioral and emotional side-effects.

Primary brain injury is the damage that occurs to the brain after the initial impact. However, a cascade of events may trigger secondary injury resulting in ongoing cellular damage to the brain, which is responsible for many of the neurological issues associated with TBI.

Three Specific Brain Injury Symptoms Depending on Brain Region Affected:

  1. Injury to the frontal lobes will cause changes in behavior and loss of cognitive functions.
  2. Injury to the cerebellum will cause loss of balance and coordination.
  3. Injury to the brainstem causes changes in heart rate and arousal.

Symptoms of mild to moderate TBI can include headaches, dizziness, nausea, and amnesia — these injuries usually resolve within days to weeks after the incident. In some cases, these injuries can also lead to long-term neurological issues.

The Most Common Symptoms of TBI:

  • Severe pain
  • Hyperarousal (low mood and energy levels)
  • Sleep disorders
  • Behavioral changes
  • Mood swings
  • Muscle spasticity
  • Convulsions and seizures
  • Confusion
  • Cognitive dysfunction
  • Impaired learning and memory

This is where CBD can help — with a growing body of research finding the endocannabinoid system plays a major role in repair mechanisms of the brain [2].

Potential Benefits of CBD for Traumatic Brain Injury

The plant Cannabis sativa contains over 80 biologically active chemicals called phytocannabinoids.

The two major phytocannabinoids are tetrahydrocannabinol (THC), and cannabidiol (CBD). Both compounds are involved in the body’s own endocannabinoid system (ECS).

Endocannabinoids, are those that are created naturally within the human body, and their receptors are found throughout the brain and many other organs and tissues.

CBD is the main non-psychoactive cannabinoid that’s been receiving a lot of attention recently. It can dampen or stimulate endocannabinoid receptors. Unlike THC, CBD is safe at high doses without any of the undesirable psychological side-effects.

Evidence has shown that the ECS is activated in response to injury and trauma, suggesting that it’s a significant part of the brain’s repair mechanisms. For example, CBD has been found to have neuroprotective effects in Alzheimer’s disease and Parkinson’s disease, multiple sclerosis and epilepsy.

Promising studies in mice have found that short term (2-7 days) treatment with CBD prevents cognitive and emotional impairment, and continues to reduce neuroinflammation for a further 21 days after TBI [3].

Let’s get into three of the main potential benefits of CBD for traumatic brain injuries:

1. CBD is Neuroprotective

Advances in neuroscience research have revealed the mechanisms that lead to TBI’s neurological symptoms such as poor motor control, cognitive decline and post-traumatic epilepsy.

Multiple changes occur to neuronal circuits of the brain within minutes after head trauma. While damage to brain cells starts immediately after the event, other changes in neurotransmitters can happen gradually, particularly after mild impact.

Neurotransmitters influence neurons in one of three ways:

  • Excitatory — increases activity
  • Inhibitory — decreases the activity
  • Modulatory — can either increase or decrease the activity

Glutamate is a major excitatory neurotransmitter, and γ-aminobutyric acid (GABA) is the major inhibitory neurotransmitter. It’s crucial that these two neurotransmitters remain in balance for the brain to function normally.

Within the first hour after a TBI event, glutamate responds in either of two ways:

  1. Glutamate is released immediately following the injury and something known as glutamate-induced neurotoxicity occurs, causing neuronal injury, cell death and dysfunction of the surviving neurons.
  2. Glutamate release is delayed, this leads to cognitive and motor (muscle) dysfunction.

This neurotransmitter disruption initiates a cascade of events that wreak havoc on normal cellular function.

New research has found that CBD can protect against this glutamate-induced cell death, by reducing oxidative stress and preserving brain cells, leading to faster healing and recovery [4].

2. CBD is Anti-inflammatory

The ECS system plays an important role in the regulation of inflammation, and CBD has long been recognized for its powerful anti-inflammatory properties.

In TBI, an immediate inflammatory response occurs, causing significant neuroinflammation and neurodegeneration — neuro, as in neurons in the brain. Damage to the brain causes activation of microglial. These specialized cells are macrophages that clean up any dead neurons and release inflammatory chemicals. Acute neuroinflammation is meant to limit further injury to the brain and start the repair process.

Chronic neuroinflammation, which can be one of the side effects of brain injuries, leads to prolonged microglial activity. This results in increased oxidative stress and neuronal damage or death.

The cannabinoids exert their anti-inflammatory effects in a few different ways, including:

  • Lowering excitotoxicity (glutamate-induced)
  • Inducing apoptosis (programmed cell death to remove diseased or damaged cells)
  • Enhancing vasodilation (improving blood flow to the area to speed healing)
  • Decreasing pro-inflammatory cytokines (reducing overall inflammation in the brain)
  • Inhibition of cell proliferation (preventing further destruction of the brain tissue)

3. CBD May Reduce Anxiety & Depression Symptoms

Individuals with TBI frequently suffer from behavioral issues, anxiety, and depression.

In fact, two-thirds of TBI patients receive antidepressant medications during their rehabilitation [5].

Depression may result from changes in neurotransmitter levels, post-injury, in the brain. An emotional response to the TBI can also influence mental health, as the person struggles with a temporary or permanent disability, loss of employment, or family/social issues.

Whether depression is caused by the initial injury or a combination of both injury and the resulting stress of recovery, CBD is well studied for its calming action without the psychoactive effects of THC [6].

It’s thought that one of the primary ways CBD works to relieve symptoms of depression and anxiety is by inhibiting the reuptake of certain neurotransmitters. However, it is important to note that CBD only has these effects on certain parts of the brain [7].

Now that we’ve explained the benefits of CBD, let’s take a look at TBI in a little more detail and how CBD can be used to help.

Measuring the Severity of Traumatic Brain Injuries

TBI can range from mild to severe brain damage.

Therefore, the importance of accurately assessing the severity of a TBI is vitally important for prognosis and management.

The management of major TBI may require surgery to remove blood clots, repair skull fractures, and relieve pressure from the skull. Magnetic resonance imaging (MRI) is used to determine the extent of brain injury.

The most commonly used clinical test to assess the severity of TBI is the Glasgow Coma Scale (GCS).

The GCS is a neurological scale, in which patients are scored on the basis of clinical symptoms, and the resulting overall score classifies their injury as:

  1. Mild: score 13–15
  2. Moderate: score 9–12
  3. Severe: score <9

For the following months after the injury, patients are often vulnerable to developing behavioral, mood and anxiety disorders.

Current Treatment Options for TBI

There are no standardized treatments for TBI.

Once a patient is stable, depending on symptoms, treatment usually relies on prescription ‘psychotropic’ medications — meaning, drugs that affect a person’s mental state.

Treatment can be a combination of drugs and may involve some trial and error.

Common Medications for Traumatic Brain Injury:

  1. Narcotic analgesics
  2. Antidepressants
  3. Anxiolytics
  4. Hypnotics
  5. Stimulants
  6. Antipsychotics
  7. Antiparkinson agents

Common Side Effects of Medications:

  • Weight gain
  • Blurred vision, dry mouth
  • Muscle spasms or tremors
  • Low mood
  • Sleep disturbances
  • Sexual dysfunction
  • Drowsiness
  • Increased risk for diabetes mellitus (type 2), coronary heart disease, and stroke

Most pharmaceutical options remain ineffective — and often come with unwanted side effects.

Some types of antidepressants should be avoided as they can worsen symptoms of TBI:

  • Monoamine oxidase inhibitors (MAOIs)
  • Tricyclic antidepressants (TCA’s)

Common Types of Therapy for Traumatic Brain Injury

Patients with TBI can benefit from a multifaceted approach to treatment, with therapies including:

  1. Physical therapy
  2. Occupational therapy
  3. Cognitive therapy
  4. Speech therapy
  5. Psychological counseling
  6. Vocational counseling

Using CBD for TBI

The hours and months following TBI are a critical time of ever-changing biochemical events in the brain. Research has discovered that the endocannabinoid system modulates several of the key secondary injury cascades following TBI.

Given its multiple positive effects, CBD can be beneficial for TBI patients that have found medications such as opiates, anticonvulsants, or antidepressants inadequate in treating their symptoms.

Of course, it’s important that you first discuss with your doctor before taking any other drugs or treatments while rehabilitating from serious head injury.

A Note on Dosing CBD

If you’re using CBD oil for the first time, it’s important to start with a low dose and increase the dosage gradually.

As we are all different, the dosage will vary with each individual. Start low, and go slow.

We recommend starting with a small dose, for example, 5 mg per day, and see how you react. Increase by 5 mg per dose, no more than once every five hours.

Be patient. It may take some trial and error to get the right dose for you.

Keeping a daily journal of dosages, timings and any symptoms can help you to find your personal optimal dose. You will know when you have reached this when you start to feel an improvement in your symptoms.

Side effects are usually very mild and may include things like dry mouth, dizziness, or low blood pressure.

The World Health Organisation (WHO) states that CBD oil, in its pure state, does not cause harm or have the potential for abuse even at high doses.

Of course, the research we have discussed here is based on using high-quality CBD. It’s important you make sure you use a high-quality CBD product that is free from contaminants and artificial additives.

Final Verdict: Using CBD For Traumatic Brain Injury

More human trials are needed, but as you can see, CBD study results are very bright indeed. CBD is promising to be a safe, and effective treatment for many of the symptoms of TBI.

TBI can affect someone both physically and mentally. It can forever change someone’s relationships, employment, finances, and social interactions.

Cognitive and emotional dysfunctions are often among the most devastating consequences of TBI. Because TBI is complex, there is no cure or single drug that can be used to treat the many and varied symptoms. There is good evidence that CBD may be an effective treatment in preserving brain cell function and other debilitating side effects of TBI, thus improving quality of life.


  1. Dewan, M. C., Rattani, A., Gupta, S., Baticulon, R. E., Hung, Y.-C., Punchak, M., … Park, K. B. (2018). Estimating the global incidence of traumatic brain injury. Journal of Neurosurgery, 1–18. https://doi.org/10.3171/2017.10.JNS17352
  2. Schurman, L. D., & Lichtman, A. H. (2017). Endocannabinoids: A Promising Impact for Traumatic Brain Injury. Frontiers in pharmacology, 8, 69. doi:10.3389/fphar.2017.0006
  3. Mori, M. A., Meyer, E., Soares, L. M., Milani, H., Guimarães, F. S., & de Oliveira, R. M. W. (2017). Cannabidiol reduces neuroinflammation and promotes neuroplasticity and functional recovery after brain ischemia. Progress in Neuro-Psychopharmacology and Biological Psychiatry, 75, 94–105. https://doi.org/10.1016/J.PNPBP.2016.11.005
  4. Schurman, L. D., & Lichtman, A. H. (2017). Endocannabinoids: A Promising Impact for Traumatic Brain Injury. Frontiers in Pharmacology, 8, 69. https://doi.org/10.3389/fphar.2017.00069
  5. Hammond, F. M., Barrett, R. S., Shea, T., Seel, R. T., McAlister, T. W., Kaelin, D., … Horn, S. D. (2015). Psychotropic medication use during inpatient rehabilitation for traumatic brain injury. Archives of Physical Medicine and Rehabilitation,96(8), S256–S273e14. https://doi.org/10.1016/j.apmr.2015.01.025
  6. Blessing, E. M., Steenkamp, M. M., Manzanares, J., & Marmar, C. R. (2015, October). Cannabidiol as a Potential Treatment for Anxiety Disorders. Neurotherapeutics. Springer. https://doi.org/10.1007/s13311-015-0387-1
  7. Crippa, J. A., Guimarães, F. S., Campos, A. C., & Zuardi, A. W. (2018). Translational Investigation of the Therapeutic Potential of Cannabidiol (CBD): Toward a New Age. Frontiers in immunology, 9, 2009. doi:10.3389/fimmu.2018.02009

More Health Benefits to Explore

Trending Articles

Trending Articles