Have you been through an injury which still causes you physical pain?

Has it been more than three months or longer than your healthcare provider had assured you?¹

If yes, then you might be suffering from a condition known as ‘chronic pain’.

Chronic pain is a common but complex condition that usually presents as a result of injury or disease.² The International Association for the Study of Pain defines chronic pain as pain which has persisted beyond normal tissue healing time, which is considered as 3 months’ time in the absence of other factors.³ Research suggests that in the UK, 13-50% of adults experience chronic pain and that in some cases, pain is disabling.²

Chronic pain has many physical, psychological and social risk factors, but all are equally distressing to the individual experiencing it, as it can drastically lower their quality of life. While Chronic pain cannot be cured, it can be effectively managed through a number of medical procedures, physical therapy, lifestyle changes and medications, including cannabis.

But wait, isn't cannabis an addictive, dangerous substance? Didn't my high school teachers, parents and half of Hollywood tell me to steer clear of that?

Yes, it is, and yes, they did, but it is a proven way to improve the quality of life of those suffering from chronic pain, and it might be the answer to your pain. Let's see how!¹

Understanding chronic pain

Pain is an important signal from the body and usually serves to alert us to harmful changes in the body, like broken bones or injured organs, or helps us to avoid something damaging, like hitting our toe against a table; this pain helps keep us safe. This type of pain starts suddenly, and when its cause is treated and healed, the pain alleviates. This is known as acute pain and is characterised by short, intense or throbbing sensations that are isolated to one region of the body or are spread throughout.¹

Chronic pain is sometimes an acute pain condition that persists for longer than 3-6 months and resolves when the underlying condition is treated. In most cases, however, chronic pain conditions occur for no known reason, and they serve no purpose. Your body might be in perfect condition, and yet pain is present, disrupting daily life. Chronic pain is characterised by dull, aching, burning or tingling sensations. It cannot be easily resolved, but can be managed by a multifaceted approach.¹

Chronic pain is generally caused by osteoarthritis or other conditions affecting the joints, back issues, diseases of muscle and bone like bursitis, tendonitis, fibromyalgia, and osteoporosis and neurological problems like migraine and nerve damage.⁴

Chronic pain has debilitating effects on the everyday life of the sufferer, such as: ⁵

• Increased risk for developing mental health issues such as anxiety, major depressive disorder, substance abuse and suicidal ideation
• Decline in cognitive processes like memory and attention
• Disturbed sleep
• Increase in cardiovascular diseases like hypertension
• Impaired sexual function

What is medical cannabis?

“Medical cannabis” is an umbrella term for all cannabis-derived substances that are used as medicines.⁶ “Cannabis” refers to all products derived from the plant Cannabis sativa, which has around 540 chemical substances. “Cannabinoids” are a group of substances found in the cannabis plant, of which the most important ones are Tetrahydrocannabinol(THC) and Cannabidiol(CBD).⁷

THC and CBD act on the body’s endocannabinoid system to treat chronic pain.⁷ The endocannabinoid system consists of endocannabinoids, which are molecular keys produced by the body, and cannabinoid receptors CB1 and CB2, which are like locks that are spread throughout the body. When endocannabinoids bind to CB1 and CB2, the sensation of pain is lowered. This system also regulates memory, movement, inflammation and metabolism.⁸

THC has a molecular structure closely resembling that of the body’s endocannabinoids and can, therefore, interact with the locks that are cannabinoid receptors CB1, which are mostly found in the brain and nervous system, to reduce the brain’s perception of pain.⁸

CBD indirectly interacts with CB2 receptors to reduce inflammation by signalling the body to produce more endocannabinoids and increase their binding to CB2 receptors, which are mainly found in cells responsible for the body's inflammatory response, thus lowering pain due to inflammation.⁸

Medical cannabis is generally taken as a capsule, syrup or spray.^6,8

Medical cannabis is prescribed in the UK only to treat severe forms of epilepsy, vomiting, and nausea caused by chemotherapy treatments, and for muscle stiffness and muscle spasms due to multiple sclerosis.⁶

It is not prescribed for the management of chronic pain in the UK, as the evidence supporting successful pain management with medical cannabis is not strong enough to warrant it.⁶

How can medical cannabis improve your quality of life?

Medical cannabis has shown the potential for lowering pain through interacting with the body’s endocannabinoid system.⁹ The endocannabinoid system also regulates memory, movement, appetite, metabolism, salivation, lacrimation or tear generation, immunity and cardiopulmonary function, all of which are adversely affected in the presence of persistent pain.^5,8 Management of chronic pain can positively impact these functions and improve the quality of life of the patient in the following ways:

Pain relief

Lowering the intensity of pain in specific or widespread areas of the body itself brings relief to patients, especially those suffering from osteoarthritis, fibromyalgia and back issues, as pain relief can rejuvenate easy movement of limbs. It can improve anxiety and depression caused due to chronic pain. THC and CBD are known to have mood-stabilising effects.^10,11,12

Reduction in inflammation

Cannabidiol (CBD) interacts with the endocannabinoid system to reduce inflammation in the body, thereby eliminating the root cause of pain.¹³ Such a path to pain relief can lower the burden of disease and free the patient to live comfortably. This is especially beneficial in arthritis and fibromyalgia.^14,15

Alternative to opioids

Opioids like morphine, oxycodone, and fentanyl are routinely used to treat acute and chronic pain effectively; however, it carries a high risk of abuse, addiction, and several medical issues like lowered immunity, obesity, gastrointestinal pain and the issues that plague a patient when they do quit opioid painkillers, such as nausea, vomiting, insomnia, and anxiety.¹⁶ 

On the other hand, cannabis use has fewer side effects, and research finds that in some individuals, using cannabis with opioids resulted in lowering the amount of opioids used and that taking only cannabis was more effective in treating pain than opioids. The research study also found that taking cannabis produced the same amount of pain relief as opioids do in some individuals, making cannabis a more favoured and safer choice of pain relief medication.¹⁷ 

Improved sleep quality

Chronic pain causes disruptions in sleep patterns and makes it difficult to fall asleep.⁵

Cannabis has been found to improve the quality of sleep and the ease with which one can fall asleep^[18] through pain relief, reduced anxiety, and relaxation of the body and mind.^8,18

Muscle relaxation and relief from muscle spasms

Patients with multiple sclerosis or spinal cord injury experience muscle spasms, which are sudden and involuntary stiffening of muscles that can be painful. Cannabis is known to relieve muscle stiffness and pain, as THC has muscle-relaxing properties.^19,20,21 As of 2018, people in the UK can be treated with the cannabis-based drug Sativex for muscle spasms when alternative options produce no relief.²²

Challenges and risks

Cannabis has faced significant restrictions primarily due to its psychotropic effects and is often associated with recreational use, resulting in social stigma. As a result, cannabis remains illegal in numerous countries or is heavily controlled.²²

Compared to other drug substances, cannabis is heavily under-researched and much of what is known about its medical use is sidelined by the debate around its legal status. Legislation concerning cannabis makes it harder for chronic pain sufferers to access it. In the UK, medical cannabis can be prescribed only to treat severe forms of epilepsy, vomiting and nausea caused by chemotherapy and muscle stiffness due to multiple sclerosis and not chronic pain.⁶

Even if you are eligible to get a medical cannabis prescription, you should be aware of the various side effects, such as: ⁸

• Mild effects—increased heart rate, visual and hearing distortion, sensory overwhelming, low blood pressure, conjunctivitis, hunger, dry throat, mouth, and eyes
• Severe effects— panic attacks, muscle spasms, psychosis, severe vomiting, inhalation burns, acute respiratory distress syndrome (ARDS), and bronchospasm – any one of which may result in hospitalisation or the necessity of emergency medical services
• Lethal effects due to long-term use—increased risk of heart attack, stroke, lung cancer and breathing problems. Prolonged use of cannabis may also lead to addiction, alter brain development, and cause depression and anxiety

It is incredibly important to seek professional medical advice to ascertain the best way to manage your chronic pain. Using non-prescription, unregulated or illegal cannabis carries more risks than benefits, as it may contain heavy metals and carcinogenic insecticides and herbicides.^23,24 It is crucial to find the right form of cannabis to minimise side effects and alter dosage to suit your health condition to prevent the chances of developing an addiction. Using cannabis under medical supervision ensures optimal treatment of chronic pain. 

Summary

Medical cannabis can be used to relieve chronic pain in patients. It is derived from the Cannabis sativa plant, and contains active compounds like THC and CBD that interact with the body’s endocannabinoid system to reduce pain and inflammation. THC modifies pain perception through CB1 receptors in the brain, while CBD reduces inflammation by enhancing CB2 receptor activity in immune cells.

Studies have found benefits for chronic pain sufferers, including pain relief, reduced inflammation, better sleep, and muscle relaxation. Additionally, cannabis offers a safer alternative to opioids, which pose risks of addiction and severe side effects.

However, due to regulatory restrictions and limited research, medical cannabis is not widely prescribed for chronic pain in many countries, including the UK. With further evidence, it may become a more accessible and effective tool for managing chronic pain and improving quality of life.