Quercetin Phytosome

  1. Quercetin bound to sunflower-sourced phosphatidylcholine to enhance absorption
  2. Helps stabilize mast cells that store and release histamine
  3. Provides support for patients who suffer from allergies
  4. An antioxidant flavonoid



Education – Quercetin 


Mast Cell Activation Disease 


Purchasing Supplements

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One Capsule Contains:
Quercetin Phytosome (Sophora japonica concentrate (leaf) / Phosphatidylcholine complex from Sunflower) 250 mg

Other Ingredients: Hypromellose (derived from cellulose) capsule, Microcrystalline Cellulose, Leucine, Silicon Dioxide.


Product Description

Widely distributed in the plant kingdom, quercetin is the most abundant of the flavonoid molecules. It is found in many foods, including apples, onions, teas, berries, vegetables of the cabbage family, seeds, and nuts.


The crucial advantage that is attributable to Quercetin Phytosome is its advanced phytosome technology. Phytosome complexes are created by a patented process that binds a botanical extract to phosphatidylcholine, a key component of cell membranes. In the case of Quercetin Phytosome, quercetin is combined with sunflower-sourced phosphatidylcholine to create a phytosome complex that easily crosses the gut barrier.*


Quercetin has many beneficial effects on human health. Probably its most well-known mechanism of action involves stabilization of mast cell membranes, which helps to decrease the release of histamine.* Other benefits include cardiovascular support and protection of the gastrointestinal tract.* A number of quercetin’s beneficial effects appear to be due to its antioxidant activity.* Quercetin scavenges free radicals and inhibits the oxidation of LDL cholesterol.* By itself, and when paired with vitamin C, quercetin reduces the incidence of oxidative damage to skin and nerves caused by glutathione depletion.*


Drug Interactions with Quercetin

While the clinical significance has not yet been established, Quercetin has been shown to inhibit P-gp, a transporter that affects blood levels and central nervous system levels of certain drugs. As a result of this inhibition, it may be possible that Quercetin can decrease blood levels but at the same time increase central nervous levels of fentanyl, morphine, methadone and possibly oxycodone. This could result in either increased or decreased therapeutic effect and/or side effects. When taking Quercetin while also taking these medications, caution should be emphasized by monitoring for changes in responsiveness to the medications and it may be necessary to reduce the dose of these medications to avoid side effects.

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.


Reference Publications

Quercetin –  Overviews

  1. Quercetin | University of Maryland Medical Center
  2.  Quercetin Attenuates Inflammatory Responses in BV-2 Microglial Cells
  3. Quercetin and derivatives: useful tools in inflammation and pain management. – PubMed – NCBI


Quercetin – COVID-19

  1. Quercetin and Vitamin C – An Experimental, Synergistic Therapy for the Prevention and Treatment of SARS-CoV-2 Related Disease (COVID-19) – 2020
  2. Quercetin Is More Effective than Cromolyn in Blocking Human Mast Cell Cytokine Release and Inhibits Contact Dermatitis and Photosensitivity in Humans – 2012
  3. Quercetin Inhibits the Production of IL-1β-Induced Inflammatory Cytokines and Chemokines in ARPE-19 Cells via the MAPK and NF-κB Signaling Pathways – 2020
  4. Quercetin and Its Anti-Allergic Immune Response – 2016

Quercetin – COMT inhibitor

  1.  Phytochemicals Inhibit Catechol-O-Methyltransferase Activity in Cytosolic Fractions from Healthy Human Mammary Tissues – Implications for Catechol Estrogen-Induced DNA Damage – 2004


Quercetin – Drug Interactions

  1. Overview of P-glycoprotein inhibitors – a rational outlook – 2012
  2. Emerging Significance of Flavonoids as P-Glycoprotein Inhibitors in Cancer Chemotherapy – 2009
  3. Herbal modulation of P-glycoprotein. [Drug Metab Rev. 2004] – PubMed – NCBI


Quercitin – Green tea

  1. Quercetin increased bioavailability and decreased methylation of green tea polyphenols in vitro and in vivo


Quercetin – Liver Disease

  1. Antioxidants in liver health – 2015

Quercetin – Nanoformulations

  1. Quercetin – Natural Medicines – Professional

Emphasis on Education


Accurate Clinic promotes patient education as the foundation of it’s medical care. In Dr. Ehlenberger’s integrative approach to patient care, including conventional and complementary and alternative medical (CAM) treatments, he may encourage or provide advice about the use of supplements. However, the specifics of choice of supplement, dosing and duration of treatment should be individualized through discussion with Dr. Ehlenberger. The following information and reference articles are presented to provide the reader with some of the latest research to facilitate evidence-based, informed decisions regarding the use of conventional as well as CAM treatments.


For medical-legal reasons, access to these links is limited to patients enrolled in an Accurate Clinic medical program.


Should you wish more information regarding any of the subjects listed – or not listed –  here, please contact Dr. Ehlenberger. He has literally thousands of published articles to share on hundreds of topics associated with pain management, weight loss, nutrition, addiction recovery and emergency medicine. It would take years for you to read them, as it did him.


For more information, please contact Accurate Clinic.


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