1. Clinical & Scientific Overview
Quercetin Phytosome (Bioflavonoid Nutraceutical) (TIP-MED-000644, Reference Code [SUP-20]) is classified under
Dietary Supplements & Nutraceuticals (FSSAI / ICMR-NIN) as a Clinical Nutrition & Nutraceutical Science • Pentahydroxyflavone Plant Polyphenol, Mast-Cell Stabiliser & Zinc Ionophore.
Within the Indian regulatory and compendial framework, it is governed under FSSAI Nutraceutical Botanical/Bioflavonoid Ingredient..
FSSAI Licensed Health Supplement / Nutraceutical Formulations (RDA Compliant)
Nutraceutical Supplemental Range: 250–500 mg once or twice daily (Sunflower lecithin Phytosome dispersion improves oral bioavailability by up to 20-fold over crystalline quercetin dihydrate, which has <2% aqueous solubility).
Clinical Nutrition, ICMR-NIN RDA & FSSAI Nutraceutical Profile
Quercetin
Pentahydroxyflavone Plant Polyphenol, Mast-Cell Stabiliser & Zinc Ionophore
Red onions (outer rings), capers, apples (peel), moringa leaves, berries, and green tea; commercially extracted from Sophora japonica flower buds
ICMR-NIN 2024 Recommended Dietary Allowance (RDA) & Tolerable Upper Intake Limit (UL): Nutraceutical Supplemental Range: 250–500 mg once or twice daily (Sunflower lecithin Phytosome dispersion improves oral bioavailability by up to 20-fold over crystalline quercetin dihydrate, which has <2% aqueous solubility).
Deficiency Clinical Syndromes vs Chronic Excess / Hypervitaminosis Risks: Safe at 500–1,000 mg/day for up to 12 weeks; very high doses (>1,000 mg/day chronically) or IV administration carry nephrotoxicity risk in pre-existing kidney disease.
Drug–Nutrient Chelation & Timing Interactions: IMPORTANT DRUG INTERACTIONS: Quercetin inhibits intestinal and hepatic CYP3A4, CYP2C8, CYP2C9, OATP1B1, and P-glycoprotein (P-gp), AND competitively binds the bacterial DNA gyrase site of Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin) — separate or avoid co-administration with cyclosporine, digoxin, midazolam, warfarin, and fluoroquinolones!
FSSAI Health Supplement vs Therapeutic Drug Distinction: FSSAI Nutraceutical Botanical/Bioflavonoid Ingredient.
3. Mechanism of Action & Pharmacodynamics
Scavenges peroxynitrite and superoxide radicals, inhibits mast-cell histamine/leukotriene degranulation by blocking Ca2+ influx and PKC theta, inhibits xanthine oxidase, and acts as an intracellular zinc ionophore.
4. Therapeutic Indications & Evidence-Supported Uses
- Physiological & Biochemical Role: Scavenges peroxynitrite and superoxide radicals, inhibits mast-cell histamine/leukotriene degranulation by blocking Ca2+ influx and PKC theta, inhibits xanthine oxidase, and acts as an intracellular zinc ionophore.
- Dietary Sources: Red onions (outer rings), capers, apples (peel), moringa leaves, berries, and green tea; commercially extracted from Sophora japonica flower buds
- ICMR-NIN RDA & Upper Limits: Nutraceutical Supplemental Range: 250–500 mg once or twice daily (Sunflower lecithin Phytosome dispersion improves oral bioavailability by up to 20-fold over crystalline quercetin dihydrate, which has <2% aqueous solubility).
🇮🇳 Jurisdiction & Indication Note: Indications and schedules reflect Indian compendial and regulatory records (CDSCO / Indian Pharmacopoeia & NFI / NLEM 2022). Where international reference labels (US FDA DailyMed / NCBI StatPearls) are cited for pharmacokinetic or mechanistic parameters, international approvals do not automatically imply CDSCO approval in India.
5. Educational Dosage Context, Formulations & Administration
Educational Dosing & Regimen Summary: Nutraceutical Supplemental Range: 250–500 mg once or twice daily (Sunflower lecithin Phytosome dispersion improves oral bioavailability by up to 20-fold over crystalline quercetin dihydrate, which has <2% aqueous solubility).
Administration & Meal Timing: IMPORTANT DRUG INTERACTIONS: Quercetin inhibits intestinal and hepatic CYP3A4, CYP2C8, CYP2C9, OATP1B1, and P-glycoprotein (P-gp), AND competitively binds the bacterial DNA gyrase site of Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin) — separate or avoid co-administration with cyclosporine, digoxin, midazolam, warfarin, and fluoroquinolones!
6. Pharmacokinetics, Metabolism & Renal/Hepatic Adjustment
Salt-form and meal-timing dependent gastrointestinal absorption; see bioavailability and drug-nutrient chelation notes (IMPORTANT DRUG INTERACTIONS: Quercetin inhibits intestinal and hepatic CYP3A4, CYP2C8, CYP2C9, OATP1B1, and P-glycoprotein (P-gp), AND competitively binds the bacterial DNA gyrase site of Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin) — separate or avoid co-administration with cyclosporine, digoxin, midazolam, warfarin, and fluoroquinolones!).
Incorporated into cellular coenzyme pools, metalloproteins, or membrane phospholipids.
Caution with magnesium, potassium, calcium, vitamin D, and high-dose vitamin C/collagen (oxalate) in Chronic Kidney Disease.
Caution with fat-soluble vitamins and concentrated lipophilic extracts in hepatobiliary disease.
7. Contraindications, Precautions & High-Risk Warnings
- Supratherapeutic megadosing above the ICMR-NIN Tolerable Upper Intake Level (UL) without medical indication
- Safe at 500–1,000 mg/day for up to 12 weeks; very high doses (>1,000 mg/day chronically) or IV administration carry nephrotoxicity risk in pre-existing kidney disease.
Key Clinical Precautions: Safe at 500–1,000 mg/day for up to 12 weeks; very high doses (>1,000 mg/day chronically) or IV administration carry nephrotoxicity risk in pre-existing kidney disease.
8. Adverse Effects Profile
- Safe at 500–1,000 mg/day for up to 12 weeks; very high doses (>1,000 mg/day chronically) or IV administration carry nephrotoxicity risk in pre-existing kidney disease.
- Safe at 500–1,000 mg/day for up to 12 weeks; very high doses (>1,000 mg/day chronically) or IV administration carry nephrotoxicity risk in pre-existing kidney disease.
9. Major Drug–Drug, Drug–Food & Drug–Herb Interactions
- IMPORTANT DRUG INTERACTIONS: Quercetin inhibits intestinal and hepatic CYP3A4, CYP2C8, CYP2C9, OATP1B1, and P-glycoprotein (P-gp), AND competitively binds the bacterial DNA gyrase site of Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin) — separate or avoid co-administration with cyclosporine, digoxin, midazolam, warfarin, and fluoroquinolones!
10. Clinical Monitoring, Patient Counselling & Storage
Clinical & Laboratory Monitoring: Verify whether the patient requires physiological nutritional maintenance (<=1 RDA under FSSAI) or high-dose therapeutic deficiency correction (Schedule H/medical supervision), and check for multi-supplement stacking.
Pharmacist Patient Counselling Points:
- IMPORTANT DRUG INTERACTIONS: Quercetin inhibits intestinal and hepatic CYP3A4, CYP2C8, CYP2C9, OATP1B1, and P-glycoprotein (P-gp), AND competitively binds the bacterial DNA gyrase site of Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin) — separate or avoid co-administration with cyclosporine, digoxin, midazolam, warfarin, and fluoroquinolones!
- Check all multivitamin and wellness labels to avoid accidentally doubling up on fat-soluble vitamins (A, D, E, K), iron, or zinc.
- Health supplements support normal physiological nutrition and are NOT intended to diagnose, treat, cure, or prevent disease under Section 22 of the FSS Act, 2006.
Storage, Stability & Dispensing Safeguards: Store in a cool, dry place below 25°C away from moisture and direct sunlight; verify FSSAI License Number and Veg/Non-Veg symbol on packaging.
11. Visual Pharmacology & Mechanism Diagram (svg-v339-01-adme-12-step-journey)
12. Authoritative References, Regulatory Sources & Editorial Disclaimer
Primary Compendial & Guideline Reference: ICMR-NIN (National Institute of Nutrition) Nutrient Requirements and Recommended Dietary Allowances (RDA) for Indians (2020/2024); FSSAI (Health Supplements, Nutraceuticals, Food for Special Dietary Use, Food for Special Medical Purpose, Functional Food and Novel Food) Regulations, 2022.
Official Verification Portals: ICMR-National Institute of Nutrition (NIN) — Dietary Guidelines & Nutrient Requirements for Indians • FSSAI — Food Safety and Standards (Health Supplements and Nutraceuticals) Regulations
Last Medically & Pharmaceutically Reviewed: 2026-11-10 • Verification Status: VERIFIED_EDUCATIONAL_CONTENT
Educational & Clinical Disclaimer: This reference profile is published solely for pharmacy education, academic study, and professional clinical reference. It does not substitute for patient-specific clinical judgement, qualified specialist oncology/medical supervision, or official CDSCO/IP prescribing information. Never self-medicate with prescription, Schedule H/H1/X, NDPS, or oncology medicines.
13. Related Reference Monographs, Educational Guides & Visual Concept
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