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Home   COVID-19 treatment studies for Quercetin  COVID-19 treatment studies for Quercetin  C19 studies: Quercetin  Quercetin   Select treatmentSelect treatmentTreatmentsTreatments
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Other Treatments Global Adoption
 
Quercetin COVID-19 studies. Studies may use specific formulations for improved bioavailability. Recent:
Rizky
Khan
Kandeil.
Quercetin has been officially adopted for early treatment in part of 1 country. Submit updates/corrections.
May 26
Early, Late, PrEP, PEP Covid Analysis (Preprint) (meta analysis)
meta-analysis
Quercetin for COVID-19: real-time meta analysis of 9 studies
Details   • Statistically significant improvements are seen for ICU admission, hospitalization, recovery, cases, and viral clearance. 9 studies from 8 independent teams in 6 different countries show statistically significant improvements in isolati..
May 15
Review Rizky et al., Life Research, doi:10.53388/life2022-0205-302 (Review)
review
The pharmacological mechanism of quercetin as adjuvant therapy of COVID-19
Details   Review of in silico and clinical evidence supporting the use of quercetin for COVID-19.
May 1
Early Khan et al., Frontiers in Pharmacology
no recov., ↓33.3%, p=0.15
Oral co-supplementation of curcumin, quercetin and vitamin D3 as adjuvant therapy for mild to moderate symptoms of COVID-19 -Results from an open-label, pilot randomized controlled trial
Details   RCT 50 COVID+ outpatients in Pakistan, 25 treated with curcumin, quercetin, and vitamin D, showing significantly faster viral clearance, significantly improved CRP, and faster resolution of acute symptoms (p=0.154). Only the abstract is c..
Jan 21
In Vitro Goc et al., European Journal of Microbiology and Immunology, doi:10.1556/1886.2021.00022 (In Vitro)
In Vitro
Inhibitory effects of specific combination of natural compounds against SARS-CoV-2 and its Alpha, Beta, Gamma, Delta, Kappa, and Mu variants
Details   In Vitro study testing combinations of plant extracts and micronutrients with several variants of SARS-CoV-2. A combination of vitamin C, N-acetylcysteine, curcumin, quercetin, resveratrol, theaflavin, naringenin, baicalin, and broccoli e..
Jan 4
PrEPPEP Rondanelli et al., Life, doi:10.3390/life12010066
symp. case, ↓92.9%, p=0.04
Promising Effects of 3-Month Period of Quercetin Phytosome® Supplementation in the Prevention of Symptomatic COVID-19 Disease in Healthcare Workers: A Pilot Study
Details   RCT 120 healthcare workers, 60 treated with quercetin phytosome, showing lower risk of cases with treatment. Quercetin phytosome 250mg twice a day.
Dec 28
2021
In Vitro Munafò et al., Research Square, doi:10.21203/rs.3.rs-1149846/v1 (Preprint) (In Vitro)
In Vitro
Quercetin and Luteolin Are Single-digit Micromolar Inhibitors of the SARS-CoV-2 RNA-dependent RNA Polymerase
Details   In Vitro and In Silico study showing quercetin and luteolin inhibiting SARS-CoV-2 RNA-dependent RNA polymerase (RdRp).
Dec 14
2021
In Vitro Singh et al., Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease, doi:10.1016/j.bbadis.2021.166322 (In Vitro)
In Vitro
The spike protein of SARS-CoV-2 virus induces heme oxygenase-1: Pathophysiologic implications
Details   In Vitro study transfecting SARS-CoV-2 viral spike protein in kidney cell lines, showing syncytia formation and upregulation of the cytoprotective gene HO-1, and that quercetin, which induces HO-1, can reduce syncytia formation. Authors c..
Dec 8
2021
Early Fazio et al., Medical Science Monitor, doi:10.12659/MSM.935379 Retrospective Study of Outcomes and Hospitalization Rates of Patients in Italy with a Confirmed Diagnosis of Early COVID-19 and Treated at Home Within 3 Days or After 3 Days of Symptom Onset with Prescribed and Non-Prescribed Treatments Between November 2020 and August 2021
Details   Retrospective 158 COVID-19 patients in Italy treated with hesperidin, quercetin, indomethacin, aspirin, omeprazole, azithromycin, LMWH, and betamethasone (treatment specific for each patient), showing significantly lower hospitalization a..
Dec 2
2021
Late Shohan et al., European Journal of Pharmacology, doi:10.1016/j.ejphar.2021.1746158
death, ↓85.7%, p=0.24
The therapeutic efficacy of quercetin in combination with antiviral drugs in hospitalized COVID-19 patients: A randomized controlled trial
Details   Small RCT with 60 severe hospitalized patients in Iran, 30 treated with quercetin, showing shorter time until discharge. All patients received remdesivir or favipiravir, and vitamin C, vitamin D, famotidine, zinc, dexamethasone, and magne..
Nov 14
2021
In Vitro Bahun et al., Food Chemistry, doi:10.1016/j.foodchem.2021.131594 (In Vitro)
In Vitro
Inhibition of the SARS-CoV-2 3CLpro main protease by plant polyphenols
Details   In Silico and In Vitro study of plant polyphenols identifying quercetin, curcumin, ellagic acid, epigallocatechin gallate and resveratrol as SARS-CoV-2 3CLpro inhibitors with IC50 between 11.8µM and 23.4µM. Real-time binding was analyzed..
Sep 29
2021
In Silico Şimşek et al., Journal of Molecular Graphics and Modelling, doi:10.1016/j.jmgm.2021.108038
In Silico
In silico identification of SARS-CoV-2 cell entry inhibitors from selected natural antivirals
Details   In Silico study identifying quercetin derivatives as SARS-CoV-2 spike protein, ACE2, and neuropilin inhibitors.
Sep 1
2021
Late Zupanets et al., Zaporozhye Med. J., doi:10.14739/2310-1210.2021.5.231714
no recov., ↓29.4%, p=0.50
Quercetin effectiveness in patients with COVID-19 associated pneumonia
Details   RCT 200 patients in Ukraine, 99 treated with IV quercetin/polyvinylirolidone followed by oral quercetin/pectin, showing improved recovery with treatment.
Jul 6
2021
PrEPPEP Margolin et al., Journal of Evidence-Based Integrative Medicine, doi:10.1177/2515690X211026193
cases, ↓94.4%, p=0.003
20-Week Study of Clinical Outcomes of Over-the-Counter COVID-19 Prophylaxis and Treatment
Details   Retrospective 113 outpatients, 53 (patient choice) treated with zinc, quercetin, vitamin C/D/E, l-lysine, and quina, showing lower cases with treatment. Results are subject to selection bias and limited information on the groups is provid..
Jun 24
2021
Early Di Pierro et al., International Journal of General Medicine, doi:10.2147/IJGM.S318949
death, ↓66.7%, p=1.00
Potential Clinical Benefits of Quercetin in the Early Stage of COVID-19: Results of a Second, Pilot, Randomized, Controlled and Open-Label Clinical Trial
Details   RCT 42 outpatients in Pakistan, 21 treated with quercetin phytosome, showing faster viral clearance and lower symptom severity with treatment.
Jun 15
2021
In Vitro Kandeil et al., Pathogens, doi:10.3390/pathogens10060758 (In Vitro)
In Vitro
Bioactive Polyphenolic Compounds Showing Strong Antiviral Activities against Severe Acute Respiratory Syndrome Coronavirus 2
Details   Vero E6 In Vitro study showing curcumin, hesperidin, and quercetin significantly inhibited SARS-CoV-2 replication, and In Silico analysis with promising Mpro and spike docking results.
Jun 8
2021
Early Di Pierro et al., International Journal of General Medicine, doi:10.2147/IJGM.S318720
death, ↓85.7%, p=0.25
Possible Therapeutic Effects of Adjuvant Quercetin Supplementation Against Early-Stage COVID-19 Infection: A Prospective, Randomized, Controlled, and Open-Label Study
Details   RCT 152 outpatients in Pakistan, 76 treated with quercetin phytosome, showing lower mortality, ICU admission, and hospitalization with treatment.
Apr 8
2021
Early Aguilar et al., Journal of Advances in Medical and Pharmaceutical Sciences, doi:10.9734/jamps/2021/v23i330222 Oral Quercetin in Adult Patients as a Potential Nutraceutical against Coronavirus Disease 2019 (COVID-19)
Details   Prospective study of 52 patients treated with quercetin. There was no control group.
Jan 19
2021
Late Onal et al., Turk. J. Biol., 45:518-529 (preprint 1/19/2021)
death, ↑29.3%, p=0.57
Treatment of COVID-19 patients with quercetin: a prospective, single center, randomized, controlled trial
Details   RCT 447 moderate-to-severe hospitalized patients in Turkey, 52 treated with quercetin, bromelain, and vitamin C, showing no statistically significant difference in clinical outcomes. NCT04377789.
Nov 16
2020
PrEPPEP Arslan et al., SSRN, doi:10.2139/ssrn.3682517 (Preprint)
cases, ↓91.7%, p=0.03
Synergistic Effect of Quercetin and Vitamin C Against COVID-19: Is a Possible Guard for Front Liners
Details   Small prophylaxis RCT with 113 patients showing fewer cases with quercetin + vitamin C + bromelain prophylaxis. NCT04377789. Note that this paper disappeared from SSRN without explanation.
Oct 9
2020
Review Derosa et al., Phytotherapy Research, doi:10.1002/ptr.6887 (Review)
review
A role for quercetin in coronavirus disease 2019 (COVID-19)
Details   Review noting that quercetin has a theoretical, but significant, capability to interfere with SARS-CoV-2 replication, with results showing this to be the fifth best compound out of 18 candidates.
Jun 19
2020
Review Biancatelli et al., Frontiers in Immunology, doi:10.3389/fimmu.2020.01451 (Review)
review
Quercetin and Vitamin C: An Experimental, Synergistic Therapy for the Prevention and Treatment of SARS-CoV-2 Related Disease (COVID-19)
Details   Review of the evidence for the use of vitamin C and quercetin both for prophylaxis in high-risk populations and for the treatment of COVID-19 patients.
Apr 24
2020
In Silico Sekiou et al., ChemRxiv, doi:10.26434/chemrxiv.12181404.v1 (Preprint)
In Silico
In-Silico Identification of Potent Inhibitors of COVID-19 Main Protease (Mpro) and Angiotensin Converting Enzyme 2 (ACE2) from Natural Products: Quercetin, Hispidulin, and Cirsimaritin Exhibited Better Potential Inhibition than Hydroxy-Chloroquine Against COVID-19 Main Protease Active Site and ACE2
Details   In Silico study of natural compounds identifying quercetin, curcumin, hispidulin, cirsimaritin, sulfasalazine, and artemisin as potential compounds that inhibit SARS-CoV-2.
Please send us corrections, updates, or comments. Vaccines and treatments are both valuable and complementary. All practical, effective, and safe means should be used. No treatment, vaccine, or intervention is 100% available and effective for all current and future variants. Denying the efficacy of any method increases mortality, morbidity, collateral damage, and the risk of endemic status. 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.
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