Early studies indicate that medicinal cannabis may have potential in treating the symptoms of COVID-19.
COVID-19 shows no sign of slowing down just yet and vaccines are still several months away, perhaps even a year. The rush to try drugs already on the market has led to dramatic purchases by some governments in a bid to reduce the impact of such an insidious virus.
With so many health professionals looking for a cure – or, failing that, the best preventative strategy aside from masks and social distancing – it is worthwhile taking a step back to see what role medicinal cannabis may play in helping to reduce the severity of symptoms brought about by COVID-19.
How does the coronavirus work?
COVID-19 uses its spiky surface proteins to grab on to receptors found on healthy cells, particularly those found in the lungs. These viral proteins distinctively go through ACE2 receptors; and once they have made their way inside, the coronavirus seizes healthy cells and takes command. Eventually, it kills some of the healthy cells.
The virus impacts the respiratory system by moving down your respiratory tract, which includes your mouth, nose, throat, and lungs. However, because the lower airways have more ACE2 receptors than the rest of the respiratory tract, COVID-19 is more likely to go deeper than other viruses such as the common cold. This is what makes COVID-19 more sinister than average colds or strains of influenza. By entering the lungs, the virus makes it difficult for people to breathe, particularly if it leads to pneumonia.
For most people (about 80%), the symptoms end with a cough and a fever. For those who are not so lucky, the infection can become very severe. About five to eight days after symptoms begin, some people will have shortness of breath which could lead to acute respiratory distress syndrome (ARDS) a few days later.
What can cannabis do?
Cannabinoids such as cannabidiol (CBD) have a history of safe use and contain several properties which may be useful in treating certain medical symptoms: CBD has anti-inflammatory properties, can act as a vasorelaxant and has the ability to reduce pain and anxiety. In combination with other cannabinoids and terpenes, as well as necessary clinical intervention, CBD has much potential to treat the symptoms of a virus such as COVID-19. Whole plant cannabis extracts have also been shown to reduce blood coagulation in animal models; it is known that many of the negative systemic effects of COVID-19 appear to be related to altered coagulation, so it is possible that cannabis may be useful in managing these sequelae.
Can medicinal cannabis help to prevent or treat COVID-19?
To date, the range and scope of verifiable research data linking cannabinoids with COVID-19 prevention is highly limited; however, novel approaches to the prevention of COVID-19 include a single study examining the possibility of incorporating CBD into oral solutions, such as mouthwashes and throat gargling liquids, with a view to ‘lowering or modulating ACE2 levels in high-risk tissues’. Studies have found that ACE2 levels change during the progression of COVID-19 and therefore the ability to modulate these levels becomes particularly important as ACE2 has been shown to be essential for lung function in animal models of SARS viruses.
Reducing severity and impact
In analyses of COVID-19 there has been a significant degree of interest in the phenomenon of cytokine storm syndrome, wherein too many cytokine proteins are released in the body: these proteins can attack the lungs and overwhelm the immune system with hyperinflammation. Early evidence has tentatively indicated that CBD and THC may be beneficial in the treatment of patients whose bodies’ inflammatory response has become pathogenic.
Much research in this field has focused on the ability of cannabinoids and terpenes to lower the immune system’s response without suppressing it. Early findings in a study currently being conducted by terpene manufacturer Eybna and cannabis research and development firm CannaSoul Analytics, both from Israel, appear to indicate that the combination of terpenes and cannabinoids used is up to two times more effective than the corticosteroid dexamethasone, when used to reduce inflammation from COVID-19. The study has not yet been peer reviewed.
Another new approach currently being investigated in Israel is the development of a potential cell therapy treatment which uses CBD-loaded exosomes to treat COVID-19 patients. The intention of this technology is to ‘target both central nervous system indications and the COVID-19 coronavirus’. CBD-loaded exosomes hold the potential to provide a highly synergistic effect of anti-inflammatory properties by targeting specific damaged organs, such as infected lung cells.
What can be done to increase research in this field?
Research into the medicinal potential of cannabis is notorious for the complexity of its application processes and the difficulty of sourcing cannabis. In Australia, using CBD only – with no THC content – in research activities requires the academic institution to apply for a special licence to allow it to obtain and store the cannabinoid, because it is still a Schedule 9 drug despite having no psychoactive properties.
The COVID-19 pandemic is likely to continue for many months yet; and this may not be the last novel coronavirus we face in our lifetime. Therefore, it is incumbent on all governments to make studying the potential of alternative medicine, such as cannabis, much easier for research institutions and private laboratories to undertake.