Traumatic Brain Injuries (TBIs) can result from full contact sports, military combat, car accidents, and even everyday slips and falls. 2.8 million Americans report TBIs each year. Patients have varying success treating the condition with pharmaceuticals. Scientists and struggling TBI patients worldwide are curious– could medical marijuana help?

What is a TBI?

Brain injuries caused by an external impact to the head can temporarily or permanently disrupt normal brain functioning. Concussions are the most common type of brain injury, but any severity of TBI can disrupt a patient’s life. Some patients with TBIs experience long-term, debilitating symptoms.

Someone who’s just had a bump, blow, or jolt to the head or body may display unusual mood, behavior, or personality changes. They may appear dazed or confused, and show a variety of other signs. Forgetfulness, moving slowly or clumsily, and loss of consciousness (even briefly) may be additional clues that a concussion or other type of TBI has occurred. 

The symptoms that may indicate a concussion include: 

  • Headache or “pressure” in head
  • Nausea or vomiting
  • Balance problems or dizziness, or double or blurry vision
  • Bothered by light or noise
  • Feeling sluggish, hazy, foggy, or groggy
  • Confusion, or concentration or memory problems
  • Just not “feeling right,” or “feeling down”

Oftentimes, these symptoms can be temporary, but sometimes they persist over the long term. In the days and weeks following a concussion, a physician or caregiver should continue to check for unusual behaviors that the injured person may be experiencing. In very rare cases, a dangerous collection of blood (hematoma) can form that may squeeze the brain against the skull and needs immediate medical attention. A few symptoms to watch for include one pupil appearing larger than the other, drowsiness or inability to wake up, and a headache that gets worse and does not go away. Additional danger signs to look out for can be found here. 

How Are TBIs Treated?

The initial trauma caused by a TBI creates instant and ongoing changes in the brain, including the release of glutamate and the production of free radicals and other inflammatory chemicals. A moderate to severe TBI can also increase the risk of seizures during the first week after the injury; medications to limit damage to the brain after a traumatic brain injury may include anti-seizure drugs. Anticonvulsants like sodium valproate, gabapentin, topiramate and carbamazepine can sometimes prevent the spread of a seizure within the brain and offer protection against possible effects that may result in brain damage.

Severe TBIs can result in significant swelling of the brain. This pressure reduces blood flow and oxygen supply to the brain, which can damage brain tissue. In some cases, a patient may be induced into a temporary coma. The theory behind this is that a comatose brain needs less oxygen to function. This can be especially helpful if blood vessels, compressed by increased pressure in the brain, are unable to supply brain cells with normal amounts of nutrients and oxygen. 

Given intravenously to people with traumatic brain injury, osmotic diuretics can also be used for a short period to reduce the edema and intracranial pressure experienced after a TBI. These drugs (Osmitrol, Resectisol) work to reduce the amount of fluid in tissues and help reduce pressure inside the brain.

Head injuries that cause bleeding in the brain may need surgery to stop the bleeding. Surgery may also be used to relieve pressure by draining accumulated fluid or creating a window in the skull that provides more room for swollen tissues.

Treatment for TBIs varies greatly depending on the type and severity of injury incurred and many can be difficult to treat. In addition to the previously mentioned treatments, patients suffering with TBIs may also be prescribed anti-anxiety medications, antidepressants, muscle relaxants, or stimulants to help ease symptoms. 

Could Cannabis Help Treat a TBI? 

Humans naturally generate endocannabinoids, which are suspected to help with blood flow and neuroplasticity. We know that cannabinoids have some neuroprotective effects and could prevent the release of inflammatory compounds after brain damage to potentially minimize stress. Much of the research being done to study medical marijuana for TBIs focuses on the short-term aftermath of the injury, when the brain is at its most vulnerable. While limited, the available research does show promise:

  • A research team at the Hebrew University of Jerusalem suggested in 2017 that the endocannabinoid 2-AG, naturally released by the body, could help protect the brain. The anti-inflammatory compound is released in higher amounts after trauma, as a kind of self-protective mechanism. When researchers administered greater amounts of 2-AG to mice after a brain injury, motor and cognitive abilities improved in the following months. While promising, this study showed that both cannabinoid receptors, CB1 and CB2, are part of the response, which makes it harder to pinpoint the mechanism at play.
  • A study in 2011 showed that cannabidiol (CBD) reduced seizures, brain edema, and motor skills for injured newborn pigs. 
  •  A 2014 study showed that TBI patients who tested positive for THC had a 2.4% death rate, down from 11.5%, although the significance is not as clear as in a controlled study. “A positive THC screen is associated with decreased mortality in adult patients sustaining TBI,” the study concluded.

Overall, the research that we do have on TBIs suggests that the protective function would be most effective in the hours following a TBI, in near-immediate response to the trauma. The “window of opportunity” to prevent secondary damage to the brain is brief. The research suggests that CBD might expand that window.

If you have had a traumatic brain injury or care for someone who has, and would like to consider medical marijuana as a therapy to help treat your symptoms, you may have questions. Reach out to us at


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  • Gabrielle Dion

    Medicate OH's Founder and Publisher is a native of Cincinnati, Ohio and holds an undergraduate degree in journalism and a master's degree in public administration, both from Northern Kentucky University. She has more than 20 years of experience writing and editing professionally for the medical and wellness industries, including positions with The Journal of Pediatrics, Livestrong, The Cincinnati Enquirer, and Patient Pop.