Summary of COVID-19 cannabidiol studies
Studies
Meta Analysis
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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 inhibits SARS-CoV-2 with Vero E6 and Calu-3 cells. Mouse study showing CBD significantly inhibited viral replication in the lung and nasal turbinate. Authors note that CBD does not inhibit ACE2 expression or the main viral proteases, inhibition occurs after viral entry. Authors stress several limitations for use at this time, including purity, quality, and the formulation of products, and potential lung damage based on administration method. Authors recommend clinical trials, but do not mention the existing RCT by Crippa et al.
Jan 2022, Science Advances, https://www.science.org/doi/10.1126/sciadv.abi6110, https://c19p.org/nguyen
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: 0.45 [0.36-0.57] versus 0.43 [0.34-0.55].
Jan 2023, SSRN Electronic J., https://www.ssrn.com/abstract=4336513, https://c19p.org/mannumbethrenjithlal
Retrospective 1,831 hospitalized COVID-19 patients in the USA, showing lower mechanical ventilation and ICU admission, but no significant difference in mortality.
Aug 2022, J. Cannabis Research, https://jcannabisresearch.biomedcentral.com/articles/10.1186/s42238-022-00152-x, https://c19p.org/shover
Retrospective 72,501 COVID-19 patients in the USA showing cannabis use associated with higher risk of hospitalization and ICU admission.
Jun 2024, JAMA Network Open, https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2820235, https://c19p.org/griffith
UK Biobank retrospective showing a higher risk of COVID-19 cases with a history of cannabis use.
Jun 2022, Chronic Diseases and Translational Medicine, https://onlinelibrary.wiley.com/doi/10.1002/cdt3.38, https://c19p.org/lehrer2
13,099 patient cannabidiol prophylaxis study: 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.
Mar 2022, Frontiers in Public Health, https://www.frontiersin.org/articles/10.3389/fpubh.2022.829715/abstract, https://c19p.org/huang2
Retrospective 800 e-cigarette users in the USA, showing higher risk of COVID-19 diagnosis and symptoms with cannabis use.
Mar 2022, Addictive Behaviors, https://www.sciencedirect.com/science/article/pii/S0306460321003555, https://c19p.org/merianos
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].
Oct 2021, Cannabis and Cannabinoid Research, https://www.liebertpub.com/doi/full/10.1089/can.2021.0093, https://c19p.org/crippa
1. Nguyen et al., Cannabidiol inhibits SARS-CoV-2 replication through induction of the host ER stress and innate immune responses
2,424 patient cannabidiol prophylaxis study: 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 inhibits SARS-CoV-2 with Vero E6 and Calu-3 cells. Mouse study showing CBD significantly inhibited viral replication in the lung and nasal turbinate. Authors note that CBD does not inhibit ACE2 expression or the main viral proteases, inhibition occurs after viral entry. Authors stress several limitations for use at this time, including purity, quality, and the formulation of products, and potential lung damage based on administration method. Authors recommend clinical trials, but do not mention the existing RCT by Crippa et al.
Jan 2022, Science Advances, https://www.science.org/doi/10.1126/sciadv.abi6110, https://c19p.org/nguyen
2. Mannumbeth Renjithlal et al., Cannabis Use and COVID-19 Hospitalization Outcomes. A Retrospective Study
39,285 patient cannabidiol prophylaxis PSM 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: 0.45 [0.36-0.57] versus 0.43 [0.34-0.55].
Jan 2023, SSRN Electronic J., https://www.ssrn.com/abstract=4336513, https://c19p.org/mannumbethrenjithlal
3. Shover et al., Cannabis consumption is associated with lower COVID-19 severity among hospitalized patients: a retrospective cohort analysis
1,831 patient cannabidiol prophylaxis PSM study: 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.
Aug 2022, J. Cannabis Research, https://jcannabisresearch.biomedcentral.com/articles/10.1186/s42238-022-00152-x, https://c19p.org/shover
4. Griffith et al., Cannabis, Tobacco Use, and COVID-19 Outcomes
72,501 patient cannabidiol prophylaxis study: 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.
Jun 2024, JAMA Network Open, https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2820235, https://c19p.org/griffith
5. Lehrer et al., Association of cannabis with chronic obstructive pulmonary disease and COVID-19 infection
cannabidiol prophylaxis study: 24% more cases (p=0.009).UK Biobank retrospective showing a higher risk of COVID-19 cases with a history of cannabis use.
Jun 2022, Chronic Diseases and Translational Medicine, https://onlinelibrary.wiley.com/doi/10.1002/cdt3.38, https://c19p.org/lehrer2
13,099 patient cannabidiol prophylaxis study: 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.
Mar 2022, Frontiers in Public Health, https://www.frontiersin.org/articles/10.3389/fpubh.2022.829715/abstract, https://c19p.org/huang2
7. Merianos et al., 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
800 patient cannabidiol prophylaxis study: 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 2022, Addictive Behaviors, https://www.sciencedirect.com/science/article/pii/S0306460321003555, https://c19p.org/merianos
8. Crippa et al., Cannabidiol for COVID-19 Patients with Mild to Moderate Symptoms (CANDIDATE Study): A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
91 patient cannabidiol late treatment RCT: 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].
Oct 2021, Cannabis and Cannabinoid Research, https://www.liebertpub.com/doi/full/10.1089/can.2021.0093, https://c19p.org/crippa
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