Cannabis and its compounds hold the potential to limit the “susceptibility and severity of infection” from COVID-19, while also showing promise in the treatment of long COVID symptoms such as anxiety, depression and decreased appetite, according to a new study.
Researchers at Dalhousie University in Canada carried out a comprehensive review of the scientific literature, publishing their findings about marijuana as a preventive therapeutic in the Journal of Clinical Medicine late last month.
The study found that “cannabinoids have been shown to prevent viral entry, mitigate oxidative stress, and alleviate the associated cytokine storm” of early COVID-19 infections.
“Post-SARS-CoV-2 infection, cannabinoids have shown promise in treating symptoms associated with post-acute long COVID-19, including depression, anxiety, post-traumatic stress injury, insomnia, pain, and decreased appetite,” it said.
The research takes into account a long list of existing studies, aiming to fill the knowledge gap on how endocannabinoid system (ECS) modulation might impact patients in the early- and post-infection stages. Prior studies have focused on marijuana as treatment option during the acute phase of a COVID-19 infection.
“Cannabis and cannabinoid-based drugs have shown promise in preventing viral entry, acting as an anti-inflammatory agent, and improving many symptoms associated with post-acute SARS-CoV-2 infections,” the authors concluded.
“Cannabinoids have the potential to be used as a preventive approach to limiting the susceptibility and severity of COVID-19 infections by preventing viral entry, mitigating oxidative stress, and alleviating the associated cytokine storm.”
However, the authors noted limitations of the findings, including the lack of cannabis product standardization and possible differences in how cannabinoids affect adults and youth.
“The majority of studies supporting ECS modulation as a treatment strategy have been conducted in contexts other than COVID-19, and therefore extrapolation of these findings to SARS-CoV-2 infections requires caution,” it added. “To fully understand the efficacy and safety of cannabinoid-based drugs in the context of COVID-19, further research is required.”
“Clinical trials and well-designed studies are necessary to assess the underlying mechanisms, determine optimal dosages and dosing schedules, and investigate the safety and potential side effects associated with ECS modulation in the context of viral infections. Therefore, despite the promising outlook, a comprehensive understanding of these aspects is crucial for establishing the therapeutic potential of cannabinoids and ECS modulation on the onset of COVID-19 and lingering symptoms associated with long COVID-19.”
A separate study based on hospital data that was unveiled in October found that cannabis consumers who caught COVID-19 had significantly lower rates of intubation, respiratory failure and death than people who do not use marijuana.
A 2022 laboratory study from researchers at Oregon State University, notably, found that certain cannabinoids can potentially prevent COVID-19 from entering human cells. But as doctors at UCLA have noted, that study focused on CBG-A and CBD-A under lab conditions and did not assess marijuana smoking by patients themselves.
During the early months of the COVID-19 pandemic, some cannabis advocates claimed with little evidence that marijuana or CBD could prevent, treat or even cure coronavirus infection—a claim many other advocates warned was premature and dangerous.
In March 2020, for example, former NFL player Kyle Turley—who said that medical marijuana changed his life and launched his own cannabis brand—was warned by the Food and Drug Administration and Federal Trade Commission over claims on social media that cannabis products would “prevent” and “cure” COVID-19.
Others used the pandemic as an argument in favor of marijuana legalization on different grounds. Connecticut Gov. Ned Lamont (D), for example, said in November 2020 that legalizing marijuana in his state would prevent the spread of covid by reducing travel to New Jersey.