Cannabis and Multiple Sclerosis: What You Should Know

The developing global cannabis market means patients with a host of conditions can access cannabis with fewer restrictions. Even countries that prohibit the herb often allow multiple sclerosis patients access to medical marijuana in one form or another. With this in mind, what is the dynamic between marijuana and multiple sclerosis? What about CBD and MS? Below, we discuss if cannabis might help to manage the symptoms of this autoimmune condition.

What Is Multiple Sclerosis

Multiple sclerosis (MS) is a lifelong condition that impacts the central nervous system. As an autoimmune disease, it stems from a malfunctioning immune system. We rely on this component of our physiology to defend us from external threats such as viruses and bacteria. However, sometimes our immune cells fail to recognise the cells of the body as “itself” and begin treating them like microscopic invaders.

In the case of MS, immune cells attack a component of nerve cells called the myelin sheath. Made up of proteins and fats, this insulating substance forms around nerve fibres and assists in the conduction of electric impulses. These signals, or action potentials, are used to carry out an array of physiological processes, including muscular contraction and the release of neurotransmitters.

As the immune system attacks the myelin sheaths, nervous system transmission takes a beating. Communication problems arise that prevent the brain from optimally transmitting messages to the rest of the body. This assault can reach a point where it causes permanent damage to the nerve fibres. Eventually, scar tissue starts to form where the myelin attempts to heal itself.

Types of Multiple Sclerosis

There are two primary ways in which MS starts. Around 8 out of every 10 MS patients are diagnosed with relapsing-remitting MS. This form of the disease is characterised by periods of worsening symptoms, or relapses. These episodes can last anywhere between several days and several months.

However, the symptoms always improve slightly once the episode comes to an end—a period known as remission. These windows of time between attacks can also last for a long period, even up to several years. Around 50% of patients with relapsing-remitting MS go on to experience secondary progressive MS within 15–20 years of their initial diagnosis. This form of the condition gets gradually worse over time without the pattern of relapse and remission.

Just over 1 out of every 10 MS patients experience primary progressive MS. This form of MS features symptoms that get worse over several years in a linear fashion, without the ups and downs of relapse and remission.

Causes of Multiple Sclerosis

The exact cause of MS remains unknown. Although considered an autoimmune disease, scientists have not yet figured out exactly what drives the immune system to start attacking myelin sheaths. However, certain risk factors are believed to contribute to an increased likelihood of developing the condition. These include:

• Age: People can experience the onset of MS at almost any age, but it mostly affects people between the ages of 20–40 years.
• Sex: Women are around three times more likely to experience relapsing-remitting MS.
• Family history: People are at a much higher chance of developing MS if they have a parent or sibling with the condition.
• Race: Northern Europeans are at a bigger risk of developing MS, whereas Asians, Africans, and Native Americans have a much lower likelihood.
• Vitamin D levels: Reduced vitamin D levels due to low exposure to sunlight may increase the risk of developing MS.
• Infections: Some viral pathogens, including Epstein-Barr virus, are associated with the development of MS.

Symptoms of Multiple Sclerosis

The degradation of myelin can cause a host of symptoms to arise. The most common symptoms of MS include:

Current Treatments for Multiple Sclerosis

No cure currently exists for MS, but there is a wide range of treatments available for individual symptoms of the disease. The main treatments for the major symptoms include:

• Muscle pain: This issue is primarily targeted with painkillers and physiotherapy.
• Emotional problems: Some patients respond well to cognitive behavioural therapy; others require antidepressants.
• Nerve pain: Medications such as gabapentin help to keep nerve pain under control.
• Mobility issues: Exercise, physiotherapy, wheelchairs, and stairlifts help to manage mobility issues.
• Spasms: Physiotherapy modalities such as stretching can ease spasms; medicines such as clonazepam and gabapentin are also often prescribed.

Medical Cannabis and Multiple Sclerosis Symptoms

MS certainly comes with a long list of symptoms. So, where exactly does medical marijuana fit into the picture? Before we explore the research surrounding cannabis and MS symptoms, it helps to first examine exactly how cannabis works in the body.

A Word on the Endocannabinoid System

Just as we possess a nervous system and a cardiovascular system, we also have an endocannabinoid system (ECS). Much like our other physiological systems, the ECS plays a fundamental role in how our bodies operate. While the pulmonary system helps us breathe and the nervous system keeps us ticking, the ECS helps to maintain a state called homeostasis (biological balance). Put simply, it helps the other systems in the body to operate at their sweet spots.

Researchers have found ECS components throughout the body, from the nervous system to the skin and bones. They help to fulfil a long list of functions, from regulating neurotransmitter firing to building up bone tissue. The key components of this vital system include a series of cannabinoid receptors, signalling molecules (endocannabinoids), and enzymes that make and break down these signalling molecules.

The interesting thing about cannabis? The herb contains a family of chemicals called cannabinoids. These molecules interact with the ECS and modulate it to varying degrees, ultimately influencing one of the most important systems in the body.

It turns out the ECS often plays a role in health conditions. When this system becomes disrupted, it causes a shift away from homeostasis that can sometimes manifest as disease. For example, researchers have found that some people diagnosed with MS display a dysregulated ECS.

Research conducted at Università Tor Vergata in Italy measured endocannabinoid levels^[1] in 26 MS patients, 25 healthy controls, and mice that served as a preclinical model of MS. The results indicate that relapsing MS patients had higher levels of anandamide (one of the main endocannabinoids) in samples of cerebrospinal fluid and peripheral lymphocytes (immune cells). The researchers also found elevated anandamide levels present in the mice, leading them to conclude that MS is associated with significant alterations of the ECS.

However, more human trials are required to figure out how exactly tapping into the ECS could help to strike at the root of MS. At present, the majority of studies have focused on if cannabis might help to alleviate some of the symptoms of the condition.

• Cannabis and Spasticity

Spasticity results in feelings of stiffness in MS patients, and may make it difficult for them to move. This symptom takes a toll on quality of life and often accompanies pain and weakness. Ongoing studies are exploring the potential of cannabis to reduce spasticity, and therefore increase quality of life in MS patients.

A randomised, placebo-controlled trial conducted in 2012 tested smoked cannabis against placebo^[2] in patients with treatment-resistant spasticity. Future studies hope to repeat these positive findings and edge closer toward an understanding of how cannabis could help manage this symptom.

The potential of marijuana for muscle spasms and spasticity has led numerous governments around the world to legalize cannabis-based medicines for this purpose. For example, the government of the United Kingdom made the oral spray Sativex (nabiximols) available to patients with moderate to severe spasticity. The preparation contains equal quantities of THC and CBD. Although it doesn’t work for all patients, the MS Society reports Sativex has a positive effect on the majority of patients^[3].

• Cannabis and Pain

Humans have recruited cannabis to deal with pain for thousands of years. It probably won’t surprise you to find out that the ECS also plays a key role in pain signalling pathways. Scores of anecdotal accounts from chronic pain sufferers report how THC can help ease discomfort and increase quality of life. But what does the research say?

A review paper published in the journal Frontiers in Pharmacology examines past studies that probed the pain-killing effects of the herb^[4]. The authors state that the mechanism of action involves cannabinoids interacting with neurotransmitter release from nerve endings, and that meta-analyses of clinical trials show moderate evidence for cannabis in cases of chronic pain. Future high-quality clinical trials are needed to determine the analgesic effects of different cannabinoids in MS patients.

• Cannabis and Bladder Control

As MS progresses, the immune system can damage parts of the brain and spinal cord responsible for controlling the bladder. Known as bladder incontinence, this lack of control can cause patients to urgently and frequently need to use the toilet. Interestingly, researchers are exploring the role of cannabis in bladder control^[5] in MS patients. Several cannabinoids are showing promise in this area, including CBG^[6] (cannabigerol).

• CBD and Mobility

Who hasn’t heard of CBD (cannabidiol) at this point? This non-psychotropic cannabinoid has risen to fame thanks to its clear-headed and relaxing effects. This molecule has a much different mechanism of action than THC. But as its presence in Sativex suggests, CBD oil and multiple sclerosis could be a compatible pair.

A review paper^[7] published in the journal Frontiers in Neurology breaks down studies that tested CBD against models of mobility, fatigue, inflammation, depression, and spasticity. Of course, this ongoing research offers interesting insights, but by no means does it provide conclusive findings on the efficacy of CBD.

The Difference Between Medical Cannabis and Sativex

While some countries allow MS patients access to Sativex, they remain restricted from accessing cannabis flowers, extracts, and other preparations. But does this really matter? In all likelihood, yes.

Sativex provides an accurate 1:1 ratio of THC and CBD. This mix seems to work for some patients, but cannabis offers a lot more than these two cannabinoids. The herb also produces over 100 other cannabinoids and 200 terpenes. As well as producing their own unique effects, these compounds may synergise with THC and CBD to elicit more optimal outcomes. The research remains early, but we’re likely to see customised extracts and even selectively bred chemovars for MS patients at some point in the future.

THC vs CBD for Multiple Sclerosis

Both of these compounds show promise in ongoing studies. THC produces a psychotropic effect that some patients find off-putting. However, others value this quality and find it benefits their mental state.

Overall, THC and CBD have very different effects on the ECS. Whereas THC binds directly to the main receptors, CBD impacts our endocannabinoid levels and binds to other receptors that researchers class as part of the "expanded endocannabinoid system". Cannabis and its components affect different people in different ways. Although many MS patients are limited to prescribed cannabis-based medicines, some might find they prefer one cannabinoid over the other if given the freedom to experiment.

How To Use Medical Cannabis for Multiple Sclerosis

There are many different ways to use cannabis; it largely boils down to personal preference and, again, access. Check out the most common below:

What Are the Risks of Using Medical Cannabis for Multiple Sclerosis?

Although cannabis possesses a relatively good safety profile, it also comes with its own set of side effects. Check out the side effects of the two most common cannabinoids below.

As research continues to discover the role of cannabis and its constituents in the treatment of MS, patients will likely gain access to tailored products and dosing guidelines that make using medical cannabis as safe as possible.

Of course, if you have any questions or doubts about using medical cannabis for MS, you should always discuss them with a doctor or physician first-hand.