CBD and Parkinson’s: What does the research say?
Summary:
- Parkinson’s disease is a neurological disorder that causes tremors and problems with movement.
- There is no cure for the condition, so treatment aims to ease symptoms.
- CBD is a bioactive hemp compound that’s attracting the interest of scientists and doctors due to its potential health benefits.
- Research focusing on CBD and Parkinson’s is in its infancy, but some results are promising.
Parkinson’s disease is a chronic and progressive movement disorder that affects around 10 million people worldwide.
It occurs when nerve cells in the brain die or malfunction, leading to problems with movement, balance, and coordination.
The disease typically progresses gradually, and people may only seek a diagnosis when symptoms become obvious or interfere with their daily lives. At this stage, the disease may be advanced.
Although treatments are available to relieve Parkinson’s symptoms, researchers are continually exploring potential new therapies that could change people’s lives. One such avenue of investigation is CBD and Parkinson’s disease.
CBD or cannabidiol is a naturally-occurring hemp compound that has shown potential in several areas of research. In this article, we’ll explore the current state of scientific evidence to see if CBD could help people living with Parkinson’s disease.
What is Parkinson's?
Parkinson’s disease is a nervous system disorder. It’s neurodegenerative, meaning it causes the gradual deterioration of brain and nerve cells.
The condition results from the loss of dopaminergic neurons in a part of the brain called the substantia nigra, which is located in the basal ganglia of the midbrain.
These neurons or nerve cells produce dopamine, a neurotransmitter that helps nerves communicate. The loss of these cells leads to a deficiency in dopamine in the brain. Because dopamine is essential for normal movement, the person then develops tremors, the primary symptom of Parkinson’s.
Experts are not sure why some people develop Parkinson’s, but they believe it’s a combination of genetic and environmental factors.
As yet, there is no cure and no medications that can modify the disease course, but various treatment options can provide some relief from symptoms.
Symptoms of Parkinson's
Parkinson’s symptoms are different for everyone, but the most common is usually tremors or shaking.
The tremor often begins in one hand or arm and can advance to the leg and foot on the same side of the body.
The tremor may involve rubbing the thumb and forefinger back and forth, which doctors call a ‘pill-rolling tremor.’ The hand may also tremble when at rest.
As the disease progresses, the tremor may become more pronounced and frequent.
Other symptoms of Parkinson’s disease include:
- Rigidity: Stiffness in the muscles can make it difficult to move or perform simple tasks such as buttoning a shirt.
- Bradykinesia: This refers to slowness of movement. People may take longer to walk, get out of a chair, or perform other daily activities.
- Postural instability: People may have difficulty standing up straight or maintaining balance, which increases the risk of falls.
Because Parkinson’s also affects the autonomic nervous system, people with the disease may experience:
- Changes in speech and swallowing
- Constipation
- Excessive sweating or decreased ability to sweat
- Urinary problems
- Skin problems
- Fatigue
- Sleep changes
As the disease progresses, symptoms may become more severe, and people may have difficulty with daily life. In the later stages, people may develop dementia.
CBD and Parkinson's: What does the research say?
CBD, or cannabidiol, is a natural, non-intoxicating compound found in the hemp plant. Research suggests it may help with pain, inflammation, sleep issues, and general wellbeing.
Even though much of the research is new and somewhat limited, some studies have shown promise concerning CBD and Parkinson’s disease.
Pain
Pain and inflammation can affect people living with Parkinson’s disease. In a small 2014 study of 22 people with Parkinson’s, researchers found that medical cannabis helped ease pain.
However, as medical cannabis contains both CBD and tetrahydrocannabinol (THC), it wasn’t possible to specify which compound was responsible for the results. Although animal studies suggest that CBD alone may also have this effect.
Tremors
Uncontrolled muscle movement or dystonia is a defining feature of Parkinson’s. An older 1986 study using CBD on five individuals with movement disorders found that it improved dystonia by up to 50%. However, two subjects experienced a worsening resting tremor at higher doses.
A recent 2020 study on CBD and Parkinson’s focused on the effects of Epidiolex — a prescription only medicine — on tremors in 13 participants. The United States Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA) has approved this CBD-based medication to treat two rare forms of epilepsy, but it is not currently approved to treat Parkinson’s disease.
The researchers concluded that CBD in the form of Epidiolex could be beneficial for Parkinson’s disease, but cautioned that the relatively high doses used in the study were associated with increased liver enzymes. They advise that large-scale randomised controlled trials are needed to investigate these effects fully.
Psychosis
Some individuals with Parkinson’s disease experience psychosis as a complication, particularly in the later stages. Experts estimate that up to 50% of individuals with Parkinson’s experience symptoms of hallucinations, delirium, and delusions.
Little research exists on CBD and Parkinson’s-related psychosis besides a small 2009 study. Researchers looked at the effects of CBD on six individuals experiencing psychosis for at least three months. They found that CBD successfully reduced symptom severity without causing any side effects.
Sleep
Sleep problems are common in people with Parkinson’s disease. These include insomnia, sleepiness during the day, and rapid eye movement sleep disorder (RBD).
Again, research into CBD and Parkinson’s-associated sleep issues is limited. But, a small 2014 study with four participants indicated that CBD might help with some of these disruptive symptoms.
Quality of life
Living with a chronic disease such as Parkinson’s can negatively impact quality of life because of physical symptoms and the social and emotional effects of the disease.
Researchers in a 2014 study investigated whether CBD oil could help. They selected 21 individuals with Parkinson’s disease without dementia or psychiatric complications. Participants were divided into three groups: placebo, CBD at 75 mg per day, or CBD at 300 mg per day.
Although researchers found no statistically significant differences in motor scores, there were significant differences in quality of life scores between the placebo group and those who received 300 mg of CBD daily. However, the authors caution that studies with larger sample sizes would help draw definitive conclusions.
It should also be noted that the Food Standards Agency’ s recommended maximum daily intake of consumer (non-medical) CBD is 70mg daily.
Is CBD safe?
Yes, CBD is generally considered safe. The World Health Organization (WHO) considers that CBD is well-tolerated with a good safety profile.
Despite this, like many supplements and natural remedies, CBD can interact with prescription and over-the-counter medications. Therefore, it’s important to discuss CBD with your doctor to minimise the risk of drug interactions or side effects.
Does CBD have any side effects?
Most people tolerate CBD without any issues. That said, you could experience mild side effects, such as:
- fatigue
- diarrhoea
- changes in appetite
- weight gain or loss
- drowsiness
- dry mouth
- nausea
However, please note that these side effects are often caused by exceeding the recommended daily dosage or using low quality products.
Other common treatments for Parkinson's
Doctors may recommend medications, supportive therapies such as physiotherapy, or surgery to help with Parkinson’s symptoms.
Medication
Medications can improve the primary symptoms of Parkinson’s, such as tremors and movement problems.
Levodopa is one of the most effective medications. It’s a natural chemical that converts into dopamine to restore depleted levels. Despite its effectiveness though, levodopa can cause side effects in some patients, such as agitation, confusion, and nausea. It can also cause a tremor that’s unrelated to Parkinson’s disease.
Doctors may also recommend dopamine agonists that mimic the effects of dopamine or MAO-B inhibitors that prevent the breakdown of dopamine.
These medications may not be useful for everyone and have various associated risks.
Supportive therapies
Physiotherapy, occupational therapy, and speech and language therapy can make living with Parkinson’s disease easier and help individuals manage their symptoms.
Some people may also find that making dietary changes can improve their symptoms. These changes may include increasing fibre to reduce constipation and eating small, regular meals to avoid issues such as low blood pressure and dizziness.
Surgery
In some cases, doctors may recommend a type of surgery called deep brain stimulation to treat Parkinson’s disease.
The procedure involves implanting a device similar to a heart pacemaker into the chest wall and running electrodes from the device into the parts of the brain affected by Parkinson’s. A tiny electrical current then stimulates the brain and helps ease the symptoms in some individuals.
Takeaway
CBD is a compound found in hemp plants that’s being studied for its potential therapeutic effects. Early research suggests that this natural bioactive compound may help improve the quality of life for people living with Parkinson’s disease.
Although CBD holds promise, many studies supporting its use are small and have limitations. Therefore, large-scale clinical trials are needed to understand the relationship between CBD and Parkinson’s disease.
While more research is needed on CBD and Parkinson’s, generally CBD is considered safe. But, like many supplements and natural remedies, it has the potential to interact with medications. Therefore, it’s important to speak with your doctor before taking CBD, especially if you’re under treatment for Parkinson’s disease.
Disclaimer: There is currently insufficient evidence to support the use of CBD in the condition(s) mentioned above and this text by no means reflects recommended uses. Always seek the advice of your healthcare professional if you are taking prescribed medication or are thinking of using CBD for your condition.
Written by Zia Sherrell and reviewed by our qualified expert, Moyra Cosgrove, Head of Nutrition at Naturecan, SENR Registered Nutritionist and DProf candidate at LJMU
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