The COVID-19 pandemic began to make headlines more than six months ago. And it didn’t take long for questions to arise about CBD and cannabis use effects with this new virus. There were questions about whether cannabis could increase infection rates, warnings about smoking, brands claimed it could cure or prevent disease.
Although we still don’t have answers to all our questions about cannabis and coronaviruses, the last six months have given us a better understanding of the situation thanks to scientific studies. These new studies shed some light on the potential of cannabis, but they are still at very early stages – in animal and laboratory studies – rather than the human clinical trials that would provide more conclusive answers to these questions.
“Only a CBD clinical trial on patients treated with COVID-19 could provide real answers to this question,” says Dr Donald Tashkin, professor of medicine at UCLA, who has conducted extensive research into the effects of cannabis on the lungs.
Some studies have shown that cannabis can help reduce a dangerous excess of immune system substances called cytokines, which trigger inflammation and can lead to death in patients with COVID-19. Others suggest that cannabis users may be more susceptible to COVID-19. Although these two lines of research seem contradictory, experts say that cannabis could be both beneficial and harmful to COVID-19, depending on when and how it is used.
Regarding the beneficial effects of cannabis on COVID-19, most research points to its anti-inflammatory potential and how it could treat a dangerous symptom of the virus called “cytokine storm“.
Cytokines are an important part of the body’s natural immune response, producing inflammation that normally helps to fight infections. But in the event of a serious infection, the body can be overwhelmed and release a dangerous amount of cytokines, which can cause too much inflammation. This is a cytokine storm, which can cause fever, fatigue, swelling, breathing difficulties (also known as ARDS or acute respiratory distress), nausea and death from organ failure.
Cannabis is a cytokine inhibitor, and may therefore be able to calm cytokine storms before they overwhelm the patient. Scientists are particularly interested in CBD, a cannabis-derived chemical called cannabinoid, which is known for its medicinal benefits without the usual psychotropic effects experienced with cannabis.
“CBD shows promise in reducing the cytokine storm, which seems to be the most damaging aspect of COVID-19 infection,” says Dr Frank Lucido, a family doctor in Berkeley who works with patients with medical cannabis. He adds that “any of the cannabinoids could have anti-inflammatory properties, but CBD is the most common and is not THC”.
Two Israeli cannabis research and development companies, Eybna and CannaSoul Analytics, have carried out a study on the same issue. They studied the effects of CBD and anti-inflammatory terpenes (a class of chemicals found in cannabis). Using a cellular model of cytokine storms, they found that both were able to significantly reduce cytokines. In fact, CBD and terpenes outperformed dexamethasone, a steroid recently found to be effective in reducing mortality due to COVID-19 in ventilated patients.
Cannabis use may also pose a particular risk. Studies on smoking suggest that it can increase the risk, so experts such as Tashkin urge patients to reduce their tobacco use where possible.
“I don’t think we have the data yet to answer this question,” says Tashkin, but adds that “in the absence of evidence to the contrary, it would be safer to avoid smoking any product during the COVID-19 pandemic”.
Although cannabis shows both useful and harmful potential in cases of COVID-19, scientists say much more research needs to be done before conclusive answers can be given.