A concussion is a mild traumatic brain injury caused by a sudden impact to the head or body that disrupts normal brain function. This temporary disruption leads to various short-term effects and requires careful management.
Understanding Concussions
A concussion disrupts the brain’s normal cellular processes, leading to metabolic disturbances, altered neurotransmitter release, and impaired blood flow. The brain experiences an “energy crisis,” making it vulnerable to further injury.
Common symptoms include headaches, dizziness, confusion, and concentration and memory issues. Other symptoms include sensitivity to light and sound, nausea, vomiting, and changes in mood or sleep patterns. These can appear immediately or develop days after the injury, and their severity varies.
How Cannabis Affects the Brain
Cannabis contains cannabinoids like tetrahydrocannabinol (THC) and cannabidiol (CBD), which interact with the body’s endocannabinoid system (ECS). The ECS is a complex network of receptors, enzymes, and naturally produced endocannabinoids that regulates various physiological processes, including mood, perception, coordination, memory, and cognitive function.
When THC is consumed, it primarily binds to CB1 receptors in the central nervous system, particularly in areas involved in cognitive functions and motor control. This interaction produces psychoactive effects, altering mood, perception, and cognition, and may lead to euphoria or relaxation. CBD does not directly bind to these receptors but can modulate their activity, influencing mood and anxiety without intoxicating effects.
The use of cannabis can interfere with the normal functioning of the ECS because plant-derived cannabinoids last longer than the body’s natural endocannabinoids, potentially overwhelming the system. Acute intoxication with THC can impair working and episodic memory, behavioral inhibition, and impulsivity. Chronic and heavy cannabis use, especially during adolescence, has been linked to difficulties in learning and memory, and in some cases, altered brain structure and function, although these effects may resolve with abstinence.
Specific Risks of Combining Cannabis and Concussion
Using cannabis during concussion recovery presents negative consequences due to the brain’s compromised state. Cannabis can worsen symptoms like dizziness, confusion, or headaches, making it harder to assess healing progress. Some individuals report feeling “okay” while using cannabis, leading to overexertion and a significant worsening of symptoms once use stops.
Cannabis use can also interfere with cognitive recovery, prolonging issues with memory, attention, and processing speed that are common after a concussion. Studies indicate that cannabis use, particularly THC, can acutely impair these cognitive functions in a dose-dependent manner. This impairment could make it more challenging for the brain to heal and re-establish normal neuronal pathways.
Sleep patterns, important for brain healing, can be disrupted by cannabis use. Research suggests marijuana may interfere with REM sleep cycles, affecting sleep quality or depth. Adequate restorative sleep is necessary for the brain to repair itself, and any interference could slow recovery.
There is also an increased risk of secondary injury due to impaired judgment or coordination while under the influence of cannabis. Concussed individuals may already experience balance problems, and cannabis further impairs these functions, potentially leading to falls or other accidents and additional brain trauma. While some preclinical studies suggest neuroprotective or anti-inflammatory properties of certain cannabinoids like CBD, scientific evidence supporting cannabis as a safe or effective treatment for concussion symptoms in humans is limited and often contradictory. Some studies show an association between cannabis use and a lower symptom burden in later concussion recovery, but this does not necessarily mean it speeds up overall recovery time.
Prioritizing Safe Recovery
To promote safe and effective recovery from a concussion, it is important to abstain from cannabis, alcohol, and other recreational substances. These substances can introduce additional stress to the already vulnerable brain and complicate the healing process. While some studies have explored potential benefits of certain cannabinoids for concussion symptoms, the current consensus among healthcare professionals leans towards caution due to the limited and often conflicting research on human subjects.
Concussion management generally emphasizes brain rest, especially in the initial 24 to 48 hours after the injury, by reducing activities that require significant mental and physical energy. This allows the brain to direct its resources towards healing. Gradually returning to normal routines and light physical activity, as tolerated and without worsening symptoms, is also recommended. Consulting a healthcare professional for a proper diagnosis and personalized management plan is advised to ensure the best possible recovery.