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Home » Health & Beauty » Remedies » Allergy & Sinus »


Source Naturals AllerStrength Digestive Quercetin is a type of quercetin that includes additional glucose molecules for increased solubility and bioavailability. This advanced allergy support product offers quick absorption. Enzymatically modified isoquercitrin was demonstrated to have 17 times greater bioavailability than quercetin itself in one clinical trial. Its core compound, quercetin, was shown in preliminary, in-vitro research to inhibit histamine release. Enzymatically modified isoquercitrin administered at the dose supplied in this product has been clinically demonstrated to maintain eye health during periods of seasonal discomfort.

  • Inhibits histamine release
  • Maintains eye health during periods of seasonal discomfort
  • Vegetarian
  • Yeast, dairy and egg-free
  • Gluten, soy and wheat-free
  • Sugar, starch and salt-free
  • No preservatives
  • Artificial colors, flavors and fragrance-free
* [1] Note: Unless otherwise noted, this product has not been evaluated by the Food and Drug Administration. Our natural products are not intended to diagnose, treat, cure, or prevent any disease.