Tier 2 — strong

Evaluation of the effect of quercetin treatment on CYP2C9 enzyme activity of diclofenac in healthy human volunteers

Satish Kumar Bedada, Prasad Neerati
Phytotherapy research : PTR 2018 32(2):305-311

Bibliography

PubMed
PMID 29168292
DOI
10.1002/ptr.5978
Funding
Funding was not specified in the indexed record or the disclosure metadata available for this entry.
Competing interests
A competing-interest declaration was not available in the indexed record or the disclosure metadata used for this entry.

Study snapshot

DesignOpen-label two-period sequential drug-interaction study
ModelHuman intervention research
Sample12 healthy volunteers
InterventionQuercetin 500 mg twice daily for 10 days; diclofenac 100 mg as probe
DurationControl and supplementation phases
EndpointsExposure and pharmacokinetics

What the study showed, in plain terms

Published in 2018, this source examined safety, interactions and special populations. Design: Open-label two-period sequential drug-interaction study. Sample/model: 12 healthy volunteers. The exposure or intervention was Quercetin 500 mg twice daily for 10 days; diclofenac 100 mg as probe. Follow-up or treatment period: Control and supplementation phases.

Diclofenac exposure increased while its hydroxylated metabolite decreased, supporting an interaction under the tested conditions.

Small sequential pharmacokinetic study. It does not quantify adverse-event risk or establish the same magnitude for every CYP2C9 substrate.

Continue with Quercetin Data Center

For topic-level interpretation, read Quercetin Interactions: Medicines, Evidence and Precautions. This is a related guide; the citation panel separately identifies articles that directly cite this paper.

Key findings

  • Diclofenac exposure increased while its hydroxylated metabolite decreased, supporting an interaction under the tested conditions.
  • The recorded outcome domains were Exposure and pharmacokinetics.
  • The result applies to the tested exposure: Quercetin 500 mg twice daily for 10 days; diclofenac 100 mg as probe; Control and supplementation phases.

What this study can and cannot tell us

  • Small sequential pharmacokinetic study. It does not quantify adverse-event risk or establish the same magnitude for every CYP2C9 substrate.
  • A change in blood exposure or a metabolic marker is not a demonstrated improvement in symptoms, disease events or lifespan. The tested formulation and co-administered medicines matter.
  • 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