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Medical Marijuana and Peripheral Neuropathy

Centuries ago, medical experts were aware that a solid blow to the head could result in cognitive dysfunction, loss of consciousness and a range of mental conditions. These conditions could be acute or become chronic. Although there was no means at the time to see inside the head, doctors were sure the brain could become disturbed by a head injury.

As medical science advanced, we came to understand the brain and central nervous system could be severely affected by trauma to the head. More recently, we learned it is not just the impact on the head that causes these reactions. The shaking motion can damage the brain inside the skull even though there is no injury visible through the skin.

Late in the 19th century, frequent train accidents demonstrated the whiplash style of head injury that results in a concussion. Even if the head does not strike an object, when it is propelled forward quickly and then stopped, the brain inside the skull sustains a concussion. At this time, long-term consequences of concussions became evident.

Simultaneously, sports doctors were concerned with the number of concussions sustained by football players. In 1906, a member of the Harvard Varsity team died from a head injury and drew attention to the severity of football injuries. A study at the time revealed 19 concussions in one season. Doctors noted that players might not be aware of sustaining a concussion during the play.

Without modern medical imaging, it was difficult to determine exactly when a concussion was sustained. If the injury did not result in a visible wound to the head, doctors could not detect the damage to the brain. It was almost impossible to correlate a concussion with subsequent behavioral changes.

Today, a CT scan and an MRI of your head can be used to diagnose a concussion. There may or may not be loss of consciousness with a concussion, but there will be evidence of at least a minor traumatic brain injury. Doctors can diagnose post-concussion syndrome based on a history of concussion and certain behavioral changes that often accompany the condition.

Symptoms of Post-Concussion Syndrome

Post-concussion syndrome can last for days, weeks or months following a head injury. The symptoms can vary and may set in at any time. Following a concussion, symptoms of post-concussion syndrome can include:

  • Sleep pattern disruption

  • Dizziness

  • Depression

  • Headache

  • Increased sensitivity to light and sound

  • Anxiety

  • Memory loss

  • Trouble concentrating

  • Fatigue

  • Vertigo

  • Personality changes

  • Restlessness

Following a traumatic brain injury, the presence of at least three of these symptoms indicates post-concussion syndrome. You don’t have to lose consciousness from the initial concussion to be diagnosed with post-concussion syndrome. Oddly enough, the resulting condition does not appear to have a correlation with how severe the initial blow to head was.

Post-concussion syndrome may result from a seemingly minor head injury while someone sustaining a more severe injury might not develop the condition.

The severity of your concussion and the number of concussions sustained over time are not good indicators of post-concussion syndrome. People over 40 have a higher risk of developing the condition, and women are diagnosed with post-concussion syndrome at a higher rate than men.

There is a chance that people with pre-existing mental health conditions are more likely to develop post-concussion syndrome following a concussion. Some of the symptoms are similar to those of depression and anxiety. Experts note that women may be diagnosed with post-concussion syndrome more frequently than men because they are more likely to seek medical attention, especially for behavioral symptoms.

The full physiology of post-concussion syndrome is not yet known. It results from damage to the brain that causes swelling and bleeding. The inflammation applies pressure to the brain, which can cause headaches and other symptoms.

The shakeup of a concussion also causes changes in your brain chemistry that neuroscientists cannot yet pinpoint. Neurotransmitters, the chemical messengers of the brain, are significantly affected by a concussion, and this shake up results in the symptoms of post-concussion syndrome.

There is no way to heal the brain tissue that was injured. In fact, in some cases, the injured tissue cannot be reached. The treatment for post-concussion syndrome consists of relieving the symptoms so patients can be more comfortable while the brain heals itself naturally.

Headaches and other physical pain from post-concussion syndrome are usually treated with analgesics. This type of pain is sometimes compared to migraines or nerve pain, and it often requires strong pain relievers. Pain relievers, either prescription or over the counter, can worsen post-concussion headaches if over used.

Cognitive impairments brought on by post-concussion syndrome usually resolve themselves in time. These symptoms can be debilitating in the short term, however. Cognitive therapy can be used to learn memory support systems to compensate. Taking notes and using electronic reminders can be helpful to balance loss of memory and short attention span.

The emotional symptoms of post-concussion syndrome may be the most significant. Although these, too, should resolve in time, anxiety and depression can become life-threatening when left untreated. There are some behavioral and drug therapies available to relieve anxiety and depression. Some may also assist with insomnia.

Brain healing is not something doctors have all the specifics on. In most cases, post-concussion syndrome resolves within three months of onset. But, in some cases, the condition lasts for up to a year or longer. There is little that can be done to predict or alter the timeframe for post-concussion syndrome.

Although there is no one treatment specifically designed for post-concussion syndrome, healthcare professionals will often prescribe pharmaceuticals to combat the emotional symptoms which may occur. Additionally, physical and behavioral therapies can be utilized for patients on the road to recovery.

Findings: Effects of Cannabis on Post Concussion Syndrome

It may seem counter-intuitive to add a psychoactive drug to the brain of someone who is experiencing behavioral changes as a result of a brain injury. The most serious damage that can be caused by a concussion is the chemical damage to the brain. In this area, doctors are working with non-specific information and do not have tools to help the brain heal.

A recent study showed the potential effects of cannabis for post-concussion syndrome. Elements in the cannabis reduce swelling in the brain. Swelling causes pressure, damage and pain. A traumatic injury to the brain releases toxic chemicals that cause some of the symptoms of post-concussion syndrome. Marijuana can help clear those chemicals and protect the brain from further damage.

Marijuana also increases blood supply to the brain. This is helpful because the blood brings oxygen and nutrients to help speed healing. It also carries toxins and other byproducts away from the brain. Medical marijuana is also effective in treating anxiety and depression, two symptoms of post-concussion syndrome.

Marijuana may only be treating the symptoms of post-concussion syndrome, but it has few if any side effects and it is one medicine that can address most of the symptoms of this condition. There is very little clinical research so far on the use of medical marijuana for post-concussion syndrome, but it is effective for many of the symptoms.

Referring to medical marijuana, Dr. Jeffrey Hergenrather said that, "In my opinion, there is no better drug for the treatment of anxiety disorders, brain trauma and post-concussion syndrome." Patients can use sativa-dominant strains to combat their emotional symptoms, depression, headaches and migraines. 


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