From the databaseWhat the row says.
Every entry follows the same shape: what is happening, the mechanism, and the recommendation.
Scope
Supplement × Prescription
Last verified
June 4, 2026
CautionEmerging evidence
What is happening. High-dose quercetin may inhibit CYP3A4 or transporters and could increase solifenacin adverse effects.
Mechanism. Potential CYP3A4 and transporter inhibition may increase solifenacin exposure.
Recommendation. Use cautiously and monitor dry mouth, constipation, urinary retention, blurred vision, or palpitations after starting or stopping quercetin.
Stack Score
How it moves the number.
Effect on the composite score
If both Quercetin and Solifenacin are in the same stack, this pair applies −5 to your Stack Score (per scored caution row).
The full algorithm, the clamping rules, and four worked stacks are at /methodology/stack-score.
SourcesSources, by evidence tier.
Every claim on this page is cited. PMIDs link straight to PubMed.
Reference material
1- 1U.S. National Library of Medicine. Solifenacin Succinate Tablets US Prescribing Information. 2026.Needs sourceNo link