Parkinson’s disease is the second most common neurodegenerative disease, preceded only by Alzheimer’s and dementia.
Only, instead of causing you to lose your memory, Parkinson’s affects your ability to control your muscle movements. Affecting between 5 and 19 people per every 100,000 around the globe, this disease of aging has wide-spread consequences.
Yet, while health care providers have known about Parkinson’s Disease for centuries, treatment of the condition remains challenging.
One of the biggest breakthroughs in Parkinson’s treatment was the invention of the drug Levodopa, which works to mimic one of the neurotransmitters most affected by the condition.
For many, however, the standard treatment for Parkinson’s simply isn’t enough to manage all related symptoms.
It is perhaps for this reason that a growing number of patients are expressing interest in medical cannabis.
Yet, when it comes to the science on the subject, researchers haven’t caught up with public enthusiasm.
“One sad part about the story of cannabis and Parkinson’s is that there is not a lot of clinical research supporting cannabis for [the disease],” explains Dr. Michele Ross, a neuroscientist and cannabis researcher, in an exclusive Green Flower video on cannabis & Parkinson’s.
“It’s not because it’s been shown that it doesn’t work,” she says. “They haven’t measured the right things. There hasn’t been a study looking at, say, does THC actually improve Parkinson’s mobility, or tremors, or the real aspects of the disease.”
Instead, most of the studies on the subject have been observational.
For example, a 2014 study published in the Journal of Psychopharmacology, for example, found that Parkinson’s patients given a high dose of cannabidiol (CBD) reported significant improvements in quality of life and overall well-being.
CBD is a plant chemical found exclusively in the cannabis plant.
However, while this study is intriguing, it did not examine exactly how or why the plant was helpful to patients. It simply measured their subjective experience with the herbal medicine.
The potential of cannabis for Parkinson’s Disease
Yet, when it comes to cannabis and Parkinson’s disease, not all hope is lost.
While there may not be a wealth of high-quality research on cannabis for Parkinson’s disease, there are several good reasons why so many researchers and patients are interested in the plant.
The herb contains several chemical compounds that have properties which may be helpful in Parkinson’s patients, potentially making the disease more manageable. These properties include:
Parkinson’s disease is a neurodegenerative condition. This means that, over time, nerve cells become damaged and eventually die.
“Parkinson’s is a disease where you have your dopamine cells that are important for initiating and maintaining movement, they’re the ones that are being damaged,” explains Ross.
The dopamine cells in question are motor neurons located in the basal ganglia, a motor region located deep in the center of the brain that enables the subconscious processing of movement.
When these cells begin to die off, the damage interferes with the brain’s ability to communicate conscious movements to the rest of the body.
Finding some way to prevent damage to these brain cells is necessary to prevent the continuation of Parkinson’s disease.
“If you can protect those cells from damage and from further damage and further neurodegeneration,” begins Ross, “you can halt the progression of that disease. Or, at least slow it down.”
Here’s where cannabis comes into the story.
Both cannabidiol (CBD) and tetrahydrocannabinol (THC) are neuroprotective antioxidants. In fact, even a patentowned by the U.S. Government presents the idea that CBD is a more powerful antioxidant than vitamins C and E.
“CBD is a powerful antioxidant and neuroprotectant,” says Ross. “Neuroprotectant means protecting the brain.”
Antioxidants are compounds that work to prevent damage from stress and free-radical toxicity. Free radicals are molecules that cause harm to DNA and cells, including neurons.
While the body produces free radicals naturally during cell metabolism, stress-related damage happens when the impact of these radical molecules goes unchecked by antioxidants.
Already, cannabis compounds have demonstrated neuroprotective effects in another common neurodegenerative disorder, multiple sclerosis (MS).
For example, a study published in the Journal of Neuroimmune Pharmacology back in 2015 cited evidence that oral THC treatment seemed to slow the progression of MS in human patients when compared to placebo.
In experimental laboratory and rodent models, both CBD and THC have shown neuroprotective effects in various instances of neurodegeneration and trauma.
2. Inflammation relief
The second major way that cannabis may prove helpful for Parkinson’s disease is due to the herb’s anti-inflammatory properties.
Specifically, non-intoxicating CBD is expected to have the most anti-inflammatory potential.
Finding new compounds that can successfully reduce neuroinflammation is a big deal.
When nerve cells become damaged, they swell. In the case of Parkinson’s this contributes to excess inflammation in the brain. This chronic, excess inflammation can worsen disease progression over time.
For example, a 2011 study published in the journal Plos One found that the cannabis compound reduced neuroinflammation associated with amyloid plaques in experimental models, which are protein plaques implicated in the progression of Alzheimer’s disease.
These diseases include Parkinson’s disease and Alzheimer’s disease.
In another 2011 review in Free Radical Biology and Medicine, author George Booze from the University of Mississippi Medical Center points out that there is a growing body of emerging preclinical evidence suggesting that the anti-inflammatory properties of CBD may be helpful for a variety of neurological diseases.
“CBD, we know, is anti-inflammatory,” Ross explains. “THC is both pro- and anti-inflammatory, and so sometimes they sort of negate each other. CBD is really going to be the most powerful thing to protect that brain and slow Parkinson’s.”
3. Symptom relief
While substantial clinical evidence for cannabis as a treatment of Parkinson’s Disease is lacking, anecdotal reports and case studies have been far from shy about the potential benefits of the herb.
For example, a survey of Parkinson’s patients conducted among patients at a care center in the Czech Republic found that 45 percent of Parkinson’s patients that consumed cannabis found at least some benefit to consuming the herb.
Of these, about 31 percent reported improvements in tremor. Nearly 45 percent felt that the plant improved symptoms of bradykinesia, which refers to the slowed movement often experienced by Parkinson’s patients.
Another 38 percent of those individuals found that taking cannabis also eased rigidity, even though the patients also continued to use the medications prescribed to them by their doctors throughout their self-managed cannabis regimens.
Yet, shakes and trembles are not the only symptoms of Parkinson’s Disease.
Dopamine may be the neurotransmitter responsible for motor control, but the compound also is key for interpreting sensations of pleasure and reward.
Dopamine is also implicated in attention, meaning that Parkinson’s patients also often experience changes in mood and cognition unrelated to the shear stress of having a chronic condition.
While CBD may be the primary anti-inflammatory and neuroprotective agent in medical cannabis, the herb’s more famous psychoactive constituent may be useful for those hoping to improve mood and get a handle on sleep.
Unlike CBD, early research suggests that THC stimulates the production of melatonin, which is the chemical compound that helps lull the body to sleep at night.
The euphoric effect of psychoactive cannabis may also be beneficial to Parkinson’s patients, inspiring relaxation, promoting laughter, and encouraging a positive mood.