Cannabidiol As a Treatment for COVID-19 Symptoms? A Critical Review

Background: Severe acute respiratory syndrome coronavirus 2 SARS-CoV-2 has caused >211 million infections and >5.5 million deaths within 24 months globally (WHO). Internationally, a debate emerged about potential benefits of cannabidiol (CBD) as treatment of corona virus disease-19 (COVID-19). Objective: To assess the effects of CBD in the treatment of COVID-19-related inflammatory symptoms from the literature. Methods: We searched Cochrane COVID-19 study register, CENTRAL (PubMed, Embase, CINAHL, ClinicalTrials.gov, and the WHO's International Clinical Trials Registry Platform), for studies testing CBD as inflammation intervention. All types of studies and populations were considered. All pre-clinical, clinical, and pharmacological outcomes were of interest. Results: Of 18 articles found, 9 were included: 5 in vivo animal studies, 3 in vitro human tissue studies and, 1 randomized clinical trial. Outcomes in four in vivo animal studies and three human tissue studies were immune response markers, which decreased. One in vivo study showed enhancement of monocytes. One human study did not show group differences in COVID-19 evolution. There was no information on adverse effects or drug interaction. Conclusion: There is not enough evidence to support or refute CBD as a repurpose drug to treat inflammation and other symptoms of COVID-19. Clinical trials are needed to test its efficacy and adverse effects.