Tier 2 — strong

Effect of oral treatment with quercetin on inflammatory and oxidative stress markers in patients with chronic obstructive pulmonary disease

Shivani Patel, Nathaniel Marchetti, Haleh Ganjian, Daohai Yu, Steven G Kelsen, Gerard J Criner, Umadevi S Sajjan
Pharmacological research. Natural products 2025 7:100252

Bibliography

PubMed
PMID 40503179
PubMed Central
PMC12151252
DOI
10.1016/j.prenap.2025.100252
Funding
Indexed grant support: R33 AT009991 — NCCIH NIH HHS — United States; R61 AT009991 — NCCIH NIH HHS — United States. The indexed list may not contain the complete funding declaration.
Competing interests
Reported disclosure: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Study snapshot

DesignRandomized placebo-controlled phase 2 COPD pilot
ModelHuman intervention research
Sample14 patients randomized 1:2 to placebo or quercetin
InterventionQuercetin 2,000 mg/day or placebo
Duration6 months
EndpointsSymptoms and quality of life

What the study showed, in plain terms

Published in 2025, this source examined immunity and respiratory health. Design: Randomized placebo-controlled phase 2 COPD pilot. Sample/model: 14 patients randomized 1:2 to placebo or quercetin. The exposure or intervention was Quercetin 2,000 mg/day or placebo. Follow-up or treatment period: 6 months.

Selected airway and blood biomarkers decreased from baseline in the quercetin group; symptoms showed a favorable trend.

Very small trial. Significance within one group is not proof of a significant between-group difference, and clinical benefit remains unestablished.

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

  • Selected airway and blood biomarkers decreased from baseline in the quercetin group; symptoms showed a favorable trend.
  • The recorded outcome domains were Symptoms and quality of life.
  • The result applies to the tested exposure: Quercetin 2,000 mg/day or placebo; 6 months.

What this study can and cannot tell us

  • Very small trial. Significance within one group is not proof of a significant between-group difference, and clinical benefit remains unestablished.
  • 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: PubMed abstract and indexed metadata; full methods were not independently confirmed for this entry. Missing method details, funding information or participant denominators are not inferred.

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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