NutriStack
Fluconazole and Quercetin, a caution.
Quercetin inhibits CYP3A4 and P-glycoprotein in vitro and has altered the pharmacokinetics of CYP3A4 substrates in animal models. Used alongside fluconazole, which is itself a CYP3A4 and CYP2C9 inhibitor, quercetin may further reduce metabolism of co-prescribed drugs and prolong fluconazole exposure.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- Fluconazole and Quercetin
- Pair type
- Caution
- Evidence (highest tier)
- Emerging
- Source citations
- 2 sources
- Stack Score effect
- −5 to your Stack Score (per scored caution row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Caution · Emerging evidence
Caution
What is happening. Quercetin inhibits CYP3A4 and P-glycoprotein in vitro and has altered the pharmacokinetics of CYP3A4 substrates in animal models. Used alongside fluconazole, which is itself a CYP3A4 and CYP2C9 inhibitor, quercetin may further reduce metabolism of co-prescribed drugs and prolong fluconazole exposure.
Mechanism. Quercetin is a moderate inhibitor of CYP3A4 and the MDR1 P-glycoprotein efflux pump. Stacking with fluconazole compounds inhibition of the same metabolic pathway.
Recommendation. Avoid high-dose quercetin (more than ~500 mg/day) while on fluconazole, especially if you take a statin, calcium channel blocker, benzodiazepine, or anticoagulant. Resume after finishing the antifungal course.
Stack Score
How this pair moves the number.
Effect on the composite score
If both Fluconazole and Quercetin 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 documented at /methodology/stack-score.
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