Download Image
    
Share
  
Post
c19early.org
Cannabidiol for COVID-19
12 studies with >19,000 patients
Serious outcome risk
Cannabidiol
Control
No significant improvement is seen in meta-analysis to date.
COVID-19 Cannabidiol studies · October 2026
Recent:
Torrejón-Guirado
Chiririwa.
Covid Analysis Cannabidiol for COVID-19: real-time meta-analysis of 12 studies (Version 22)
Meta-analysis using the most serious outcome reported shows 23% [-22‑95%] higher risk, without reaching statistical significance. All data and sources to reproduce this analysis are in the appendix.
May 7
 Torrejón-Guirado et al., PLOS One, doi:10.1371/journal.pone.0347098 Association between cannabis use and result of COVID-19 testing among scholarised adolescents in Andalusia: A cross-sectional study
154% more cases (p=0.001). Analysis of 1,051 adolescents aged 14-18 in Spain, showing that those testing positive for COVID-19 were approximately 2.9 times more likely to have used cannabis in the last month. Limitations include the small number of COVID-19-positiv..
Apr 28
 Chiririwa, H., Pharmaceuticals, doi:10.3390/ph19060869 Selected Cannabinoids, Cannabimimetic Agents and Artemisia Combinations as Theoretical Adjunct Strategies Against COVID-19
Review of cannabinoids, cannabimimetic compounds, and Artemisia species as potential therapeutic agents for COVID-19.
Aug 31
2025
 Fischer et al., The University of Texas at Austin, doi:10.26153/tsw/61958 Use of CBD oil for reducing the negative emotional impact of COVID-19 : a randomized clinical trial
RCT 148 outpatients showing no significant difference with CBD oil for COVID-19-related stress. This four-arm placebo-controlled trial compared three CBD oil formulations (300mg daily of CBD isolate, broad-spectrum CBD, or full-spectrum C..
Jul 25
2025
 McNamara et al., NCT04615949 Study to Evaluate the Efficacy and Safety of CardiolRx™ in Patients With COVID-19 and Cardiovascular Disease or Risk Factors A Double-blind, Placebo-controlled Trial
80% lower mortality (p=0.49). Early terminated RCT showing lower mortality with cannabidiol treatment, without statistical significance.
Feb 28
2025
 Kuntzman et al., Israel Medical Association Journal, 27:2 Cannabidiol and Its Effects on Patients with COVID-19 Infection
77% lower mortality (p=0.3), 57% lower ICU admission (p=1), and 22% shorter hospitalization (p=0.61). RCT 10 hospitalized COVID-19 patients showing potential benefit with sublingual cannabidiol (CBD) oil. There was only 7 patients in the treatment arm and 3 in the placebo group. CBD-treated patients showed a trends toward lower inflammato..
Jul 26
2024
 Milad et al., Cannabis, doi:10.26828/cannabis/2024/000248 Dried Cannabis Use, Tobacco Smoking, and COVID-19 Infection: Findings from a Longitudinal Observational Cohort Study
101% more cases (p=0.0003). Longitudinal observational cohort study of 1,343 community adults in Canada, showing increased risk of self-reported COVID-19 infection with dried cannabis use. Cannabis users were younger than the control group.
Jun 21
2024
 Griffith et al., JAMA Network Open, doi:10.1001/jamanetworkopen.2024.17977 Cannabis, Tobacco Use, and COVID-19 Outcomes
3% lower mortality (p=0.73), 27% higher ICU admission (p<0.0001), and 80% higher hospitalization (p<0.0001). Retrospective 72,501 COVID-19 patients in the USA showing cannabis use associated with higher risk of hospitalization and ICU admission.
Dec 30
2023
 Scott et al., Journal of Clinical Medicine, doi:10.3390/jcm13010227 Cannabinoids and the Endocannabinoid System in Early SARS-CoV-2 Infection and Long COVID-19—A Scoping Review
Review of the potential therapeutic role of cannabinoids and the endocannabinoid system in SARS-CoV-2 infection and long COVID-19. Authors note that early in infection, cannabinoids may prevent viral entry, mitigate oxidative stress, and ..
Jan 28
2023
 Mannumbeth Renjithlal et al., SSRN Electronic Journal, doi:10.2139/ssrn.4336513 Cannabis Use and COVID-19 Hospitalization Outcomes. A Retrospective Study
56% lower mortality (p<0.0001), 25% lower ventilation (p<0.0001), and 6% longer hospitalization (p=0.0009). Retrospective 1,657,800 COVID-19 hospitalizations in the USA including 13,095 patients with cannabis use disorder, showing lower risk of mortality with cannabis use disorder. The text and Table S2 have conflicting results for mortality: 0..
Aug 29
2022
 Ramakrishnan et al., The Journal of Clinical Psychiatry, doi:10.4088/JCP.21m14332 Impact of Cannabis Use, Substance Use Disorders, and Psychiatric Diagnoses on COVID-19 Outcomes
47% higher hospitalization (p=0.0001). Retrospective 6,291 COVID-19 patients in the USA, showing higher mean hospital admissions and higher maximum length of hospitalization with cannabis use disorder. Results for cannabis use disorder patients may differ from other use of can..
Aug 5
2022
 Shover et al., Journal of Cannabis Research, doi:10.1186/s42238-022-00152-x Cannabis consumption is associated with lower COVID-19 severity among hospitalized patients: a retrospective cohort analysis
2% lower mortality (p=0.57), 5% lower ventilation (p=0.02), 9% lower ICU admission (p=0.02), and 3% lower need for oxygen therapy (p=0.27). Retrospective 1,831 hospitalized COVID-19 patients in the USA, showing lower mechanical ventilation and ICU admission, but no significant difference in mortality.
Jun 22
2022
 Lehrer et al., Chronic Diseases and Translational Medicine, doi:10.1002/cdt3.38 Association of cannabis with chronic obstructive pulmonary disease and COVID-19 infection
24% more cases (p=0.009). UK Biobank retrospective showing a higher risk of COVID-19 cases with a history of cannabis use.
Mar 31
2022
 Merianos et al., Addictive Behaviors, doi:10.1016/j.addbeh.2021.107170 Concurrent use of e-cigarettes and cannabis and associated COVID-19 symptoms, testing, and diagnosis among student e-cigarette users at four U.S. Universities
212% more symptomatic cases (p<0.0001) and 3% more cases (p=0.33). Retrospective 800 e-cigarette users in the USA, showing higher risk of COVID-19 diagnosis and symptoms with cannabis use.
Mar 8
2022
 Huang et al., Frontiers in Public Health, doi:10.3389/fpubh.2022.829715 Cannabis use is associated with lower COVID-19 susceptibility but poorer survival
181% higher mortality (p=0.04) and 19% fewer cases (p=0.0001). UK Biobank retrospective with 13,099 cannabis users, showing a lower risk of COVID-19 infection, however regular users had a significantly higher risk of mortality.
Jan 20
2022
 Nguyen et al., Science Advances, doi:10.1126/sciadv.abi6110 (date from preprint) Cannabidiol inhibits SARS-CoV-2 replication through induction of the host ER stress and innate immune responses
50% fewer cases (p=0.006). Retrospective 1,212 patients in the USA with a history of seizure-related conditions, showing patients treated with CBD100 had significantly lower incidence of COVID-19 cases compared to a matched control group. In vitro study showing CBD..
Jan 10
2022
 van Breemen et al., Journal of Natural Products, doi:10.1021/acs.jnatprod.1c00946 Cannabinoids Block Cellular Entry of SARS-CoV-2 and the Emerging Variants
In vitro study showing that cannabigerolic acid and cannabidiolic acid inhibited SARS-CoV-2 entry into cells.
Oct 7
2021
 Crippa et al., Cannabis and Cannabinoid Research, doi:10.1089/can.2021.0093 Cannabidiol for COVID-19 Patients with Mild to Moderate Symptoms (CANDIDATE Study): A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
557% higher hospitalization (p=0.25) and 33% slower recovery (p=0.21). RCT 105 patients recruited in an ER in Brazil, 49 treated with CBD, showing no significant differences with treatment. 300mg CBD for 14 days. For discussion see [liebertpub.com].
Feb 17
2021
 Malinowska et al., International Journal of Molecular Sciences, doi:10.3390/ijms22041986 Opportunities, Challenges and Pitfalls of Using Cannabidiol as an Adjuvant Drug in COVID-19
Review of the potential benefits and concerns for the use of cannabidiol in the treatment of COVID-19.