Tier 2 — strong

Treatment of COVID-19 patients with quercetin: a prospective, single center, randomized, controlled trial

Hasan Önal, Bengü Arslan, Nurcan Üçüncü Ergun, Şeyma Topuz, Seda Yilmaz Semerci, Mehmet Eren Kurnaz, Yulet Miray Molu, Mehmet Abdussamet Bozkurt, Nurettin Süner, Ali Kocataş
Turkish journal of biology = Turk biyoloji dergisi 2021 45(4):518-529

Bibliography

PubMed
PMID 34803451
PubMed Central
PMC8573830
DOI
10.3906/biy-2104-16
Funding
Funding was not specified in the indexed record or the disclosure metadata available for this entry.
Competing interests
Reported disclosure: None of the authors have a financial relationship with a commercial entity that has an interest in the subject matter of this manuscript.

Study snapshot

DesignRandomized usual-care controlled adjunctive trial
ModelHuman intervention research
Sample429 adults with chronic disease and moderate-to-severe COVID-19 symptoms
InterventionQuercetin, vitamin C and bromelain added to routine care
DurationFrom enrollment to discharge, intubation or death
EndpointsSource-specific outcomes described in the key findings

What the study showed, in plain terms

Published in 2021, this source examined immunity and respiratory health. Design: Randomized usual-care controlled adjunctive trial. Sample/model: 429 adults with chronic disease and moderate-to-severe COVID-19 symptoms. The exposure or intervention was Quercetin, vitamin C and bromelain added to routine care. Follow-up or treatment period: From enrollment to discharge, intubation or death.

Some laboratory recovery measures improved. The combination did not reduce the risk of clinical events during follow-up.

Multi-ingredient treatment and differences in baseline pulmonary findings complicate interpretation. No clinical-event benefit was demonstrated.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin for Immune Health, Colds and COVID-19. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Some laboratory recovery measures improved.
  • The combination did not reduce the risk of clinical events during follow-up.
  • The recorded outcome domains were Source-specific outcomes described in the key findings.
  • The result applies to the tested exposure: Quercetin, vitamin C and bromelain added to routine care; From enrollment to discharge, intubation or death.

What this study can and cannot tell us

  • Multi-ingredient treatment and differences in baseline pulmonary findings complicate interpretation. No clinical-event benefit was demonstrated.
  • An individual controlled trial must be interpreted alongside its comparator, sample size, endpoint selection and independent replication. It does not validate a different commercial formulation or a general longevity claim.
  • Source basis: Source check: accessible full text and indexed metadata. Missing method details, funding information or participant denominators are not inferred.

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The therapeutic efficacy of quercetin in combination with antiviral drugs in hospitalized COVID-19 patients: A randomized controlled trial
Mojtaba Shohan et al. · European journal of pharmacology · 2022
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Oral Co-Supplementation of Curcumin, Quercetin, and Vitamin D3 as an Adjuvant Therapy for Mild to Moderate Symptoms of COVID-19-Results From a Pilot Open-Label, Randomized Controlled Trial
Amjad Khan et al. · Frontiers in pharmacology · 2022

Editorial review

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Dr. Khaled Mahmoud, MBBChCritical Care Medicine, Longevity Science & Editorial Direction Dr. Amr Yasser, PhDCardiometabolic, Musculoskeletal, Gut & Bioavailability Dr. Abdulla Mostafa, PhDCellular Senescence, Neurological, Mitochondrial & Brain-Ageing Biology