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Antioxidant

Quercetin Dihydrate (from Sophora japonica bud extract)

Also known as: quercetin, quercetin dihydrate, sophora quercetin

B
Evidence

A plant-derived bioflavonoid extracted from Sophora japonica buds with potent antioxidant and anti-inflammatory properties. Quercetin is one of the most abundant flavonoids in plant foods.

Primary uses

  • Antioxidant support
  • Anti-inflammatory response
  • Seasonal allergy support
  • Immune modulation

How it works

  • Mast cell stabilization
  • Quercetin may reduce histamine release
  • Free radical scavenging
  • NF-κB pathway modulation

Dosage

Typical range
250–1000 mg daily, often split into 2–3 doses
Timing
With meals for improved absorption
With food
With food; bioavailability enhanced by fat or quercetin transporters
Duration
Safe for continuous use; effects may accumulate over weeks
Special populations
Generally safe; those on blood thinners should monitor with healthcare provider

Forms

  • powder· 70/100
  • capsule· 70/100
  • dihydrate· 70/100

Safety

Common side effects

  • Rare; headache or stomach upset at high doses

Contraindications

  • Caution with anticoagulant/antiplatelet medications

Evidence notes

Good evidence for antioxidant and anti-inflammatory effects; moderate evidence for seasonal allergy support. Bioavailability improved with dihydrate form.

Grade B: Some human trials support key claims; further confirmation needed.

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.