Conv. Plasma
Nigella Sativa
Peg.. Lambda

All quercetin studies
Meta analysis
Home COVID-19 treatment researchQuercetinQuercetin (more..)
Melatonin Meta
Bromhexine Meta Metformin Meta
Budesonide Meta
Cannabidiol Meta Molnupiravir Meta
Colchicine Meta
Conv. Plasma Meta
Curcumin Meta Nigella Sativa Meta
Ensovibep Meta Nitazoxanide Meta
Famotidine Meta Paxlovid Meta
Favipiravir Meta Peg.. Lambda Meta
Fluvoxamine Meta Quercetin Meta
Hydroxychlor.. Meta Remdesivir Meta
Ivermectin Meta
Lactoferrin Meta

All Studies   Meta Analysis   Recent:  
0 0.5 1 1.5 2+ Mortality 67% Improvement Relative Risk ICU admission 67% Hospitalization 67% Recovery 37% Viral clearance, day 7 58% Viral clearance, day 14 -50% Viral clearance, day 21 67% Quercetin  Di Pierro et al.  EARLY TREATMENT  RCT Is early treatment with quercetin beneficial for COVID-19? RCT 100 patients in Pakistan (December 2020 - September 2021) Improved recovery (p=0.007) and viral clearance (p<0.0001) Di Pierro et al., Frontiers in Pharmac.., Jan 2023 Favors quercetin Favors control

Quercetin as a possible complementary agent for early-stage COVID-19: Concluding results of a randomized clinical trial

Di Pierro et al., Frontiers in Pharmacology, doi:10.3389/fphar.2022.1096853, NCT04861298
Jan 2023  
  Source   PDF   All Studies   Meta AnalysisMeta
RCT 100 outpatients in Pakistan, 50 treated with quercetin phytosome, showing faster viral clearance and improved recovery with treatment. Patients in the treatment group were significantly younger (41 vs. 54).
This is the 8th of 10 COVID-19 RCTs for quercetin, which collectively show efficacy with p=0.0049.
This is the 9th of 11 COVID-19 controlled studies for quercetin, which collectively show efficacy with p=0.0031. This study is excluded in the after exclusion results of meta analysis: randomization resulted in significant baseline differences that were not adjusted for.
risk of death, 66.7% lower, RR 0.33, p = 1.00, treatment 0 of 50 (0.0%), control 1 of 50 (2.0%), NNT 50, relative risk is not 0 because of continuity correction due to zero events (with reciprocal of the contrasting arm).
risk of ICU admission, 66.7% lower, RR 0.33, p = 1.00, treatment 0 of 50 (0.0%), control 1 of 50 (2.0%), NNT 50, relative risk is not 0 because of continuity correction due to zero events (with reciprocal of the contrasting arm).
risk of hospitalization, 66.7% lower, RR 0.33, p = 1.00, treatment 0 of 50 (0.0%), control 1 of 50 (2.0%), NNT 50, relative risk is not 0 because of continuity correction due to zero events (with reciprocal of the contrasting arm).
risk of no recovery, 36.8% lower, RR 0.63, p = 0.007, treatment 24 of 50 (48.0%), control 38 of 50 (76.0%), NNT 3.6, day 7.
risk of no viral clearance, 57.9% lower, RR 0.42, p < 0.001, treatment 16 of 50 (32.0%), control 38 of 50 (76.0%), NNT 2.3, mid-recovery, day 7.
risk of no viral clearance, 50.0% higher, RR 1.50, p = 1.00, treatment 3 of 50 (6.0%), control 2 of 50 (4.0%), day 14.
risk of no viral clearance, 66.7% lower, RR 0.33, p = 1.00, treatment 0 of 50 (0.0%), control 1 of 50 (2.0%), NNT 50, relative risk is not 0 because of continuity correction due to zero events (with reciprocal of the contrasting arm), day 21.
Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates
Di Pierro et al., 13 Jan 2023, Randomized Controlled Trial, Pakistan, peer-reviewed, mean age 47.6, 13 authors, study period December 2020 - September 2021, trial NCT04861298 (history).
All Studies   Meta Analysis   Submit Updates or Corrections
This PaperQuercetinAll
Quercetin as a possible complementary agent for early-stage COVID-19: Concluding results of a randomized clinical trial
Francesco Di Pierro, Amjad Khan, Somia Iqtadar, Sami Ullah Mumtaz, Muhammad Nabeel Akbar Chaudhry, Alexander Bertuccioli, Giuseppe Derosa, Pamela Maffioli, Stefano Togni, Antonella Riva, Pietro Allegrini, Martino Recchia, Nicola Zerbinati
Frontiers in Pharmacology, doi:10.3389/fphar.2022.1096853
Background: Quercetin, a natural polyphenol with demonstrated broadspectrum antiviral, anti-inflammatory, and antioxidant properties, has been proposed as an adjuvant for early-stage coronavirus disease 2019 (COVID-19) infection. Objective: To explore the possible therapeutic effect of quercetin in outpatients with early-stage mild to moderate symptoms of COVID-19. Methods: This was an open-label randomized controlled clinical trial conducted at the department of medicine, King Edward Medical University, Lahore, PK. Patients were randomized to receive either standard of care (SC) plus an oral quercetin supplement (500 mg Quercetin Phytosome ® , 1st week, TDS: 2nd week, BDS) (n = 50, quercetin group) or SC alone (n = 50, control group). Results: After one week of treatment, patients in the quercetin group showed a speedy recovery from COVID-19 as compared to the control group, i.e., 34 patients (vs. 12 in the control group) tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (p = 0.0004), and 26 patients (vs. 12 in the control group) had their COVID-19-associated acute symptoms resolved (p = 0.0051). Patients in the quercetin group also showed a significant fall in the serum lactate dehydrogenase (LDH) mean values i.e., from 406.56 ± 183.92 to 257.74 ± 110.73 U/L, p = 0.0001. Quercetin was well-tolerated by all the 50 patients, and no side effects were reported.
Ethics statement The study was approved by the Institutional Review Board, King Edward Medical University, Lahore, Pakistan via Ref. No. 192 /RC/KEMU. The patients/participants provided their written informed consent to participate in this study. Author contributions Conflict of interest FDP belongs to the Scientific Board of Pharmextracta. AB is a Pharmextracta scientific advisor. ST, PA, and AR belong to the Scientific Board of Indena. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Publisher's note All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
Abian, Ortega-Alarcon, Jimenez-Alesanco, Ceballos-Laita, Vega et al., Structural stability of SARS-CoV-2 3CL pro and identification of quercetin as an inhibitor by experimental screening, Int. J. Biol. Macromol, doi:10.1016/j.ijbiomac.2020.07.235
Bahun, Jukic, Oblak, Kranjc, Bajc et al., None
Biancatelli, Berrill, Catravas, Marik, None
Chakraborty, Sharma, Bhattacharya, Agoramoorthy, Lee, None
Chen, Li, Luo, Liu, Xu et al., Binding interaction of quercetin-3-beta-galactoside and its synthetic derivatives with SARS-CoV 3CL(pro): Structure-activity relationship studies reveal salient pharmacophore features, Bioorg Med. Chem, doi:10.1016/j.bmc.2006.09.014
Chiang, Chiang, Liu, Lin, In vitro antiviral activities of Caesalpinia pulcherrima and its related flavonoids, J. Antimicrob. Chemother, doi:10.1093/jac/dkg291
Derosa, Maffioli, D'angelo, Di Pierro, A role for quercetin in coronavirus disease 2019 (COVID-19), Phytother. Res, doi:10.1002/ptr.6887
Di Petrillo, Orrù, Fais, Fantini, Quercetin and its derivates as antiviral potentials: A comprehensive review, Phytother. Res, doi:10.1002/ptr.7309
Di Pierro, Derosa, Maffioli, Bertuccioli, Togni et al., Possible therapeutic effects of adjuvant quercetin supplementation against early-stage COVID-19 infection: A prospective, randomized, controlled, and open-label study, Am. J. Emerg. Med, doi:10.1016/j.ajem.2020.05.073
Imran, Thabet, Alaqel, Alzahrani, Abida et al., The therapeutic and prophylactic potential of quercetin against COVID-19: An outlook on the clinical studies, inventive compositions, and patent literature, Antioxidants, doi:10.3390/antiox11050876
Kalil, Patterson, Mehta, Tomashek, Wolfe et al., Baricitinib plus remdesivir for hospitalized adults with covid-19, N. Engl. J. Med, doi:10.1056/NEJMoa2031994
Kandeil, Mostafa, Kutkat, Moatasim, Al-Karmalawy et al., Bioactive polyphenolic compounds showing strong antiviral activities against severe acute respiratory syndrome coronavirus 2, Pathogens, doi:10.3390/pathogens10060758
Lan, Ge, Yu, Shan, Zhou et al., Structure of the SARS-CoV-2 spike receptor-binding domain bound to the ACE2 receptor, Nature, doi:10.1038/s41586-020-2180-5
Lee, Yu, Trimpert, Benthani, Mairhofer et al., Virus-induced senescence is a driver and therapeutic target in COVID-19, Nature, doi:10.1038/s41586-021-03995-1
Liu, Raghuvanshi, Ceylan, Bolling, Quercetin and its metabolites inhibit recombinant human angiotensin-converting enzyme 2
Onal, Arslan, Ucuncu Ergun, Topuz, Yilmaz Semerci et al., None, J. Agric. Food Chem, doi:10.1021/acs.jafc.0c05064
Ono, Nakane, Tocilizumab in patients admitted to hospital with COVID-19: A randomised, controlled, openlabel, platform trial, N. Engl. J. Med, doi:10.1016/S0140-6736(21)00676-0
Quercetin, An experimental, synergistic therapy for the prevention and treatment of SARS-CoV-2 related disease (COVID-19), Front. Immunol, doi:10.3389/fimmu.2020.01451
Rizzuti, Grande, Conforti, Jimenez-Alesanco, Ceballos-Laita et al., Rutin is a low micromolar inhibitor of SARS-CoV-2 main protease 3CLpro: Implications for drug Design of quercetin analogs, Biomedicines, doi:10.3390/biomedicines9040375
Rondanelli, Perna, Gasparri, Petrangolini, Allegrini et al., Promising effects of 3-month period of quercetin Phytosome ® supplementation in the prevention of symptomatic COVID-19 disease in healthcare workers: A pilot study, Life, doi:10.3390/life12010066
Saeedi-Boroujeni, Mahmoudian-Sani, Anti-inflammatory potential of Quercetin in COVID-19 treatment, J. Inflamm. (Lond), doi:10.1186/s12950-021-00268-6
Shohan, Nashibi, Mahmoudian-Sani, Abolnezhadian, Ghafourian et al., The therapeutic efficacy of quercetin in combination with antiviral drugs in hospitalized COVID-19 patients: A randomized controlled trial, Eur. J. Pharmacol, doi:10.1016/j.ejphar.2021.174615
Szarpak, Ruetzler, Safiejko, Hampel, Pruc et al., Lactate dehydrogenase level as a COVID-19 severity marker, Am. J. Emerg. Med, doi:10.1016/j.ajem.2020.11.025
Tőzsér, Benkő, Natural Compounds as Regulators of NLRP3
Wu, Li, Li, He, Jiang et al., Quercetin as an antiviral agent inhibits influenza A virus (iav) entry, Viruses, doi:10.3390/v8010006
Yan, Zhang, Li, Xia, Guo et al., Structural basis for the recognition of SARS-CoV-2 by full-length human ACE2, Science, doi:10.1126/science.abb2762
Yi, Li, Yuan, Qu, Chen et al., Small molecules blocking the entry of severe acute respiratory syndrome coronavirus into host cells, J. Virol, doi:10.1128/jvi.78.20.11334-11339.2004
Zupanets, Golubovska, Tarasenko, Bezuhla, Pasichnik et al., Efficacy of quercetin in patients with pneumonia associated with coronavirus disease (COVID-19), Zaporizhia Med. J
Please send us corrections, updates, or comments. Vaccines and treatments are complementary. All practical, effective, and safe means should be used based on risk/benefit analysis. No treatment, vaccine, or intervention is 100% available and effective for all current and future variants. We do not provide medical advice. Before taking any medication, consult a qualified physician who can provide personalized advice and details of risks and benefits based on your medical history and situation. FLCCC and WCH provide treatment protocols.
  or use drag and drop