Accurate Education - Quercetin for Chronic Pain: A Patient Guide

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Quercetin for Chronic Pain: A Patient Guide

Quercetin is a natural compound found abundantly in fruits and vegetables with potent anti-inflammatory and antioxidant properties that may help manage chronic pain, particularly in conditions like rheumatoid arthritis and osteoarthritis.

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Quercetin for Chronic Pain: A Patient Guide

1. OVERVIEW

Quercetin has potent anti-inflammatory and antioxidant properties that can help manage chronic pain. By inhibiting inflammatory pathways, quercetin reduces pain and joint stiffness. It also reduces free radicals which contribute to oxidative stress. .[1][2][3]

What makes quercetin valuable for chronic pain:

Similar to ibuprofen and other NSAIDs, quercetin inhibits cyclooxygenase-2 (COX-2), reducing prostaglandin production, [1][4][5]
In terms of pain processing, quercetin blocks pain triggers in pain receptors (sensory neurons), reducing pain signal transmission[6]
Quercetin suppresses NF-κB, the master regulator of inflammation[7][8]
Quercetin reduces neuroinflammation and oxidative stress in the nervous system[2][3]
By modifying nerve interactions in the spinal cord, quercetin reduces central sensitization[9]
It also helps clearing out damaged cells that contribute to chronic pain[10]

How Quercetin Compares to Conventional Medications:

Preclinical studies demonstrate that quercetin alleviates inflammatory hyperalgesia comparable to NSAIDs like diclofenac.[11] In animal models of trigeminal pain, systemic quercetin administration attenuated inflammation-induced hyperexcitability of nociceptive neurons with effects similar to diclofenac.[11] Unlike NSAIDs, quercetin does not cause gastrointestinal ulceration or cardiovascular risks with long-term use.[1][12]

A randomized controlled trial in women with rheumatoid arthritis found that 500 mg/day quercetin for 8 weeks significantly reduced morning stiffness, morning pain, after-activity pain, and disease activity scores compared to placebo.[13] Quercetin also significantly reduced plasma TNF-α levels.[13]

However, human clinical trials specifically for chronic pain conditions remain limited. Most evidence comes from preclinical studies, and the poor bioavailability of standard quercetin formulations (approximately 2% absorption) has historically limited clinical applications to human studies .[14][15] Enhanced bioavailability formulations may improve clinical outcomes.[14][16]

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2. DIETARY SOURCES

Quercetin is widely distributed in plant foods, with content varying significantly by source. High Quercetin foods include:

Onions (especially red onions): 20-40 mg per 100g – highest bioavailability source[17][18][19]
Capers: 180-230 mg per 100g (highest concentration)[20]
Red leaf lettuce: 15-30 mg per 100g[17]
Asparagus: 10-15 mg per 100g[17]
Apples (with skin): 4-7 mg per 100g[18][19]
Berries (cranberries, blueberries): 3-15 mg per 100g[15][20]
Broccoli: 3-5 mg per 100g[19]
Green tea: 2-3 mg per cup[17][19]
Red wine: 2-3 mg per glass[20]

Important Bioavailability Note: The form of quercetin significantly affects absorption:[14][18]

Quercetin glucosides from onions have the highest bioavailability (absorption ~4-fold higher than apple quercetin)[18]
Quercetin aglycone (supplement form) has very poor bioavailability (~2%)[14][15]
Enhanced formulations (phytosomes, liposomal, cyclodextrin complexes) can increase bioavailability 10-60 fold[14][16]

Note: Average dietary intake is approximately 15-20 mg/day in Western diets.[17] Therapeutic doses used in clinical trials (500-1000 mg/day) far exceed what can be obtained from diet alone, necessitating supplementation for pain management.[21][22]

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3. INDICATIONS FOR NUTRACEUTICAL SUPPLEMENTATION

Pain Conditions with Human Clinical Evidence:

Rheumatoid Arthritis – MODERATE Quality Evidence (Human RCT)

500 mg/day for 8 weeks significantly reduced morning stiffness, pain, and disease activity[13]
Reduced plasma TNF-α levels[13]
May be as effective as methotrexate for joint protection in animal models[23]

Pain Conditions with Strong Preclinical Evidence:

Osteoarthritis – Strong Preclinical Evidence

Meta-analysis of 12 animal studies showed quercetin significantly improved cartilage OARSI scores[10]
Reduces pain hypersensitivity and preserves cartilage morphology in OA models[24][25][26]
Inhibits chondrocyte apoptosis and promotes cartilage repair[27][28]

Diabetic Neuropathic Pain – Strong Preclinical Evidence

Alleviates thermal hyperalgesia in diabetic mice[9][29]
Inhibits mTOR/p70S6K pathway-mediated synaptic changes in spinal cord[9]
Reduces P2X4 receptor upregulation in dorsal root ganglia[29]

Neuropathic Pain (Nerve Injury) – Strong Preclinical Evidence

Dose-dependently alleviates thermal and cold hyperalgesia in spinal nerve ligation models[7]
Pre-administration also attenuates neuropathic pain development[7]
Inhibits Toll-like receptor signaling pathway[7]

Chronic Orofacial Pain – Strong Preclinical Evidence

Alleviates mechanical allodynia through sodium channel blockade[6]
Comparable efficacy to NSAIDs for trigeminal inflammatory pain[11]

Inflammatory Pain – Strong Preclinical Evidence

Reduces inflammatory nociception through cytokine inhibition[30]
Inhibits muscle pain from intense exercise[31]

Conditions with Theoretical Benefit:

Fibromyalgia (polyphenols show promise for central sensitivity syndromes)[32]
Cancer pain (preclinical evidence)[2]
Migraine (anti-inflammatory and vascular effects)

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4. QUERCETIN’S IMPACT ON PAIN CONDITIONS

Quercetin addresses the underlying pathophysiology of chronic pain through multiple mechanisms:

Anti-Inflammatory Actions:

Inhibits COX-2 expression and prostaglandin E2 production[1][4][5]
Suppresses NF-κB activation, reducing inflammatory gene transcription[7][8]
Reduces pro-inflammatory cytokines (TNF-α, IL-1β, IL-6)[24][27][13]
Inhibits lipoxygenase and reduces leukotriene production[3][19]
Modulates macrophage polarization toward anti-inflammatory M2 phenotype[27]

Cartilage-protective Effects (Osteoarthritis):

Inhibits matrix metalloproteinases (MMP-3, MMP-13) that degrade cartilage[25][26]
Promotes collagen II and aggrecan synthesis[25]
Reduces chondrocyte apoptosis through SIRT1/AMPK pathway activation[28]
Inhibits ferroptosis (iron-dependent cell death) in chondrocytes[25]
Acts as a senolytic, clearing senescent cells from joints[10]

Neuroprotective Effects:

Protects dorsal root ganglion neurons from inflammatory damage[24][29]
Reduces satellite glial cell activation in sensory ganglia[29]
Blocks voltage-gated sodium channels, reducing neuronal hyperexcitability[6]

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5. QUERCETIN’S IMPACT ON PAIN PROCESSING

Pain processing refers to how pain signals are processed from the initial damaged tissue source of pain through the nerves and spinal cord to the brain and then down the spinal cord again. Quercetin offers potential benefit for reducing the severity of the pain experience by acting at various levels of pain processing.

Level 1: Peripheral Pain Receptor (Nociception Transduction)

Inhibits COX-2 at the site of tissue injury, reducing prostaglandin-mediated sensitization[1][5]
Blocks voltage-gated sodium channels (Nav) in peripheral nociceptors[6]
Reduces local inflammatory mediators that activate pain receptors[30]
Scavenges reactive oxygen species that sensitize nociceptors[3][30]

Level 2: Primary Afferent Transmission to Spinal Cord

Protects dorsal root ganglion neurons from oxidative damage[33][29]
Inhibits P2X4 receptor upregulation in DRG satellite glial cells[29]
Reduces inflammatory mediator expression in DRG[7][33]
Maintains normal nerve conduction by protecting axonal integrity[34]

Level 3: Spinal Cord Dorsal Horn Processing (First Synapse)

Inhibits mTOR/p70S6K pathway-mediated synaptic plasticity changes[9]
Reduces dendritic spine density and synaptic protein levels (PSD-95, synaptophysin)[9]
Suppresses spinal cord glial cell activation (astrocytes and microglia)[31][33]
Reduces spinal cord cytokine production and oxidative stress[31][33]
Decreases c-Fos expression in dorsal horn neurons[33]

Level 4: Ascending Spinal Pathways and Supraspinal Processing

Provides neuroprotection through antioxidant mechanisms[34][35]
Reduces neuroinflammation in ascending pain pathways[34]

Level 5: Brain Cortical Processing and Pain Perception

Promotes mitochondrial biogenesis in neurons through SIRT1/PGC-1α pathway[36][37]
Protects against oxidative stress-induced neuronal damage[37]
May improve cognitive function affected by chronic pain[34]

Level 6: Descending Pain Modulation

Modulates GABAergic system function[2]
Interacts with opioidergic system[2]
Reduces central inflammatory processes that impair descending inhibition[33]

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6. BENEFITS FOR PAIN SENSITIZATION

Peripheral Sensitization: MODERATE-HIGH Quality Evidence (Preclinical)

Inhibits COX-2 and prostaglandin production that sensitize peripheral nociceptors[1][5]
Blocks voltage-gated sodium channels, reducing nociceptor hyperexcitability[6]
Reduces inflammatory cytokines at the site of injury[7][30]
Protects peripheral nerve endings from oxidative damage[3][30]
Prevents development of hyperalgesia when given prophylactically[7]

Central Sensitization: MODERATE-HIGH Quality Evidence (Preclinical)

Inhibits mTOR/p70S6K pathway-mediated synaptic plasticity changes in spinal cord[9]
Reduces dendritic spine density and synaptic protein expression[9]
Suppresses spinal cord glial cell activation (GFAP, Iba-1)[31][33]
Inhibits ERK1/2 signaling in spinal cord[33]
Reduces spinal cord NF-κB activation[33]
Decreases c-Fos expression, a marker of neuronal activation[33]

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7. QUERCETIN’S IMPACT ON THE 4 DRIVING FORCES OF CHRONIC PAIN

1. Systemic Inflammation: STRONG EFFECT

Inhibits NF-κB, the master regulator of inflammatory gene expression[7][8]
Reduces TNF-α, IL-1β, and IL-6 production[24][27][13]
Inhibits COX-2 expression and prostaglandin synthesis[1][4][5]
Suppresses lipoxygenase and leukotriene production[3]
Meta-analysis shows significant reduction in CRP at doses ≥500 mg/day[38]
Human RCT demonstrated reduced TNF-α in rheumatoid arthritis[13]

2. Neuroinflammation: STRONG EFFECT (Preclinical)

Suppresses microglial and astrocyte activation in spinal cord[31][33]
Reduces neuroinflammatory cytokine production in CNS[31]
Inhibits Toll-like receptor signaling in glial cells[7]
Protects neurons from inflammatory damage[34][37]
Reduces satellite glial cell activation in dorsal root ganglia[29]

3. Oxidative Stress: VERY STRONG EFFECT (Primary Mechanism)

This is one of quercetin’s primary mechanisms of action:

Potent direct free radical scavenger[3][39]
Inhibits multiple ROS-generating enzymes (xanthine oxidase, NADPH oxidase, lipoxygenase, myeloperoxidase)[39]
Activates Nrf2/HO-1 antioxidant pathway[25][40][31]
Restores glutathione levels[30]
Increases superoxide dismutase (SOD) and glutathione peroxidase activity[8][40]
Protects mitochondria from oxidative damage[36][35]

4. Mitochondrial Dysfunction: STRONG EFFECT

Preserves mitochondrial membrane potential under stress conditions[27][36]
Stimulates mitochondrial biogenesis through SIRT1/PGC-1α pathway[36][37]
Increases cellular NAD+/NADH ratio[36]
Restores complex I activity in metabolically stressed cells[36]
Improves oxidative respiration and ATP production[36][35]
Reduces mitochondrial ROS production[36][41]

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8. DOSING, TIMING, DURATION AND ADMINISTRATION

Recommended Dosing (Based on Human Studies):

General anti-inflammatory

Dose: 500 mg/day
Timing: With meals containing fat’
Duration: Ongoing

Rheumatoid Arthritis (RA)

Dose: 500 mg/day
Timing: With meals
Duration: Minimum 8 weeks

Osteoarthritis (theoretical)

Dose: 500-1000 mg/day
Timing: Divided doses with meals
Duration: Minimum 12 weeks

Neuropathic pain (theoretical)

Dose: 500-1000 mg/day
Timing: Divided doses with meals
Duration: Minimum 12 weeks

Key Dosing Points:

Human studies have used doses ranging from 150 mg to 1000 mg daily[21][22][13]
500 mg/day is the most commonly studied dose for anti-inflammatory effects[21][13][38]
Doses ≥500 mg/day show significant CRP reduction in meta-analysis[38]
Plasma quercetin increases dose-dependently: 178% (50 mg), 359% (100 mg), 570% (150 mg)[22] High inter-individual variation in plasma levels (36-57%)[22]

Timing:

Take with meals containing dietary fat to enhance absorption[14]
Peak plasma concentrations occur approximately 6 hours after ingestion[22]
Divided doses (morning and evening) may maintain more stable plasma levels

Duration of Onset:

Plasma levels increase within hours of first dose[22]
Anti-inflammatory effects may take 4-8 weeks to manifest clinically[13]
Allow minimum 8-12 weeks to assess clinical benefit for pain conditions

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9. FORMULATION CONSIDERATIONS

Standard Quercetin (Aglycone):

Most common supplement form
Very poor bioavailability (~2% absorption)[14][15]
Undergoes extensive first-pass metabolism in intestine and liver[42][15]
Metabolized to glucuronide, sulfate, and methylated conjugates[42]

Enhanced Bioavailability Formulations:[14]

Quercetin Phytosome (with lecithin)

Bioavailability Increase: ~20-fold
Notes: Well-studied formulation

Liposomal quercetin (LipoMicel®)

Bioavailability Increase: 7-15 fold
Notes: Maintains levels over 72 hours |[16]

Quercetin-γ-cyclodextrin complex

Bioavailability Increase: ~11-fold
Notes: Improved water solubility

Self-Emulsifying formulations

Bioavailability Increase: Up to 62-fold
Notes: Newer technology

Quercetin with dietary fat/fiber

Bioavailability Increase: ~2-fold
Notes: Simple enhancement

Notes:

Quercetin-3-O-glucoside (from onions) has better absorption than aglycone[14][18]
Isoquercetin (quercetin-3-O-glucoside) is sometimes available as supplement
Rutin (quercetin-3-O-rutinoside) has lower bioavailability than glucosides[14]

Quality Considerations:

Choose products from reputable manufacturers with third-party testing
Look for enhanced bioavailability formulations when possible
Verify quercetin content; some products contain less than labeled[43]
Store in cool, dry conditions away from light

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10. SYNERGIES WITH OTHER PAIN MEDICATIONS AND NUTRACEUTICALS

Nutraceuticals with Potential Synergy:

Bromelain: Often combined with quercetin; may enhance absorption and anti-inflammatory effects
Vitamin C: Regenerates quercetin after oxidation; commonly combined
Curcumin: Complementary anti-inflammatory mechanisms; both inhibit NF-κB
Omega-3 fatty acids: Synergistic anti-inflammatory effects
Resveratrol: Both activate SIRT1 pathway
CoQ10: Complementary mitochondrial support
NAD+ precursors (Nicotinamide Riboside (NR), NMN): Both support mitochondrial function and SIRT1 activation

Conventional Medications:

NSAIDs: Quercetin has similar COX-2 inhibitory mechanism; may allow dose reduction of NSAIDs
Gabapentinoids: Complementary mechanisms; no known interactions
Duloxetine (Cymbalta)/SNRIs: May complement through different pathways
Methotrexate: Animal studies suggest quercetin may be as effective; no antagonism observed[23]
Acetaminophen: No known interaction; complementary mechanisms

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11. DRUG INTERACTIONS

Clinically Significant Interactions:– CAUTION

Quercetin and its metabolites can displace warfarin from serum albumin[44]
High doses may increase warfarin effect and bleeding risk[44]
Monitor INR if taking quercetin with warfarin

Cyclosporine – CAUTION

Quercetin inhibits CYP3A4 and P-glycoprotein[45][46]
May increase cyclosporine blood levels
Monitor drug levels if combining

Fluoroquinolone Antibiotics – CAUTION

Quercetin may compete for renal tubular secretion
Potential for altered antibiotic levels

Moderate Interactions (Monitor):

CYP450 Substrates:

Quercetin inhibits CYP1A2, CYP2C9, CYP2C19, and CYP3A4[45][46]
May increase levels of drugs metabolized by these enzymes
Relevant drugs include: some statins, calcium channel blockers, benzodiazepines

Drug Transporters:

Quercetin inhibits OATP1B1, OATP1B3, OATP2B1, and BCRP transporters[45]
May affect absorption and distribution of substrate drugs
Relevant drugs include: statins, methotrexate, some antibiotics

Generally Safe – No Known Significant Interactions:

Acetaminophen
Gabapentinoids (gabapentin, pregabalin)
Most antidepressants
Opioids
Proton pump inhibitors

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12. SAFETY AND CONTRAINDICATIONS

Generally Favorable Safety Profile:

Quercetin has a long history of safe dietary consumption and is Generally Recognized as Safe (GRAS) by the FDA.[12] Human clinical trials report few adverse effects.[47][12]

Common Side Effects (Generally Mild):

Headache (occasional)
Mild gastrointestinal discomfort (nausea, stomach upset)
Tingling sensations in extremities (rare)

Safety Data from Clinical Trials:

8-week trial (500 mg/day): No significant adverse events vs. placebo[13]
Multiple trials up to 1000 mg/day: Well-tolerated[22][47]
No evidence of in vivo genotoxicity or carcinogenicity despite positive in vitro mutagenicity tests[12]

Contraindications:

Known allergy to quercetin or related flavonoids
Concurrent use with quinolone antibiotics (theoretical antagonism)

Use with Caution:

Pregnancy and lactation (insufficient safety data for high-dose supplementation)[47]
Patients on anticoagulants (warfarin) – monitor INR[44]
Patients on immunosuppressants (cyclosporine)[47]
Pre-existing kidney disease (theoretical concern from animal studies)[47]
Estrogen-sensitive conditions (quercetin has weak estrogenic activity)[47]

Theoretical Long-Term Concerns (Require More Research):[47]

Long-term safety data (>12 weeks) at high doses (≥1000 mg) are limited
Animal studies suggest potential to enhance nephrotoxicity in predamaged kidneys
Theoretical concerns about estrogen-dependent cancers (weak estrogenic activity)

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13. SPECIAL CONSIDERATIONS / TIPS

Bioavailability is critical: Standard quercetin has very poor absorption (~2%). Consider enhanced formulations (phytosome, liposomal) or take with dietary fat to improve absorption.[14][16]
Take with meals: Fat-containing meals significantly enhance quercetin absorption.[14]
Start with standard doses: Begin with 500 mg/day and assess tolerance before increasing.
Be patient: Allow 8-12 weeks to assess benefit for chronic pain conditions.
Consider food sources: Onions provide the most bioavailable form of quercetin; regular consumption may complement supplementation.[18]
Quality matters: Choose reputable brands with third-party testing; some products contain less quercetin than labeled.[43]
Anticoagulant caution: If taking warfarin, inform your healthcare provider and monitor INR more frequently when starting quercetin.[44]
Combination approach: Quercetin works well with other anti-inflammatory nutraceuticals (curcumin, omega-3s, vitamin C).
For osteoarthritis: Quercetin’s senolytic and chondroprotective effects make it particularly promising for joint conditions.[10]
Realistic expectations: Strong preclinical evidence exists, but human pain trials are limited. Benefits may be modest and gradual.

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14. COSTS

Standard quercetin (500 mg capsules): $10-25 per month
Enhanced bioavailability formulations (phytosome, liposomal): $25-50 per month
Quercetin + bromelain combinations: $15-30 per month
Isoquercetin (quercetin glucoside): $20-40 per month

Quercetin is one of the more affordable nutraceutical supplements. It is sold as a dietary supplement in the United States and does not require a prescription. Enhanced bioavailability formulations cost more but may provide better value due to improved absorption. Prices vary by brand and formulation.

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Remember: Quercetin is a well-studied flavonoid with potent anti-inflammatory and antioxidant properties that target multiple mechanisms underlying chronic pain—including COX-2 inhibition, NF-κB suppression, and mitochondrial protection. While preclinical evidence is strong across multiple pain conditions, human clinical trials specifically for pain are limited, with the best evidence in rheumatoid arthritis.

The excellent safety profile and low cost make quercetin a reasonable option to consider, particularly for inflammatory pain conditions and osteoarthritis. The major limitation is poor bioavailability of standard formulations, which can be addressed with enhanced delivery systems or by taking with fat-containing meals.

Always discuss any new supplement with your healthcare provider before starting, especially if you take anticoagulants or immunosuppressants.

Key differences from nicotinamide riboside (NR) include quercetin’s stronger evidence for COX-2 inhibition and direct anti-inflammatory effects, while NR has stronger evidence for mitochondrial biogenesis. Both share SIRT1 activation as a common mechanism.

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Quercetin Ameliorates CFA-Induced Chronic Inflammatory Hyperalgesia via Modulation of ROS-Mediated ERK1/2 Signaling and Inhibition of Spinal Glial Activation in Vivo. Kumar S, Vinayak M. Neuromolecular Medicine. 2020;22(4):517-533. doi:10.1007/s12017-020-08609-z.
Neuropharmacological Interventions of Quercetin and Its Derivatives in Neurological and Psychological Disorders. Agrawal K, Chakraborty P, Dewanjee S, et al. Neuroscience and Biobehavioral Reviews. 2023;144:104955. doi:10.1016/j.neubiorev.2022.104955.
Quercetin and the Mitochondria: A Mechanistic View. de Oliveira MR, Nabavi SM, Braidy N, et al. Biotechnology Advances. 2016 Sep-Oct;34(5):532-549. doi:10.1016/j.biotechadv.2015.12.014.
Quercetin Preserves Redox Status and Stimulates Mitochondrial Function in Metabolically-Stressed HepG2 Cells. Houghton MJ, Kerimi A, Tumova S, Boyle JP, Williamson G. Free Radical Biology & Medicine. 2018;129:296-309. doi:10.1016/j.freeradbiomed.2018.09.037.
Quercetin Increases Mitochondrial Biogenesis and Reduces Free Radicals in Neuronal SH-SY5Y Cells. Ho CL, Kao NJ, Lin CI, Cross TL, Lin SH. Nutrients. 2022;14(16):3310. doi:10.3390/nu14163310.
Effects of Supplementation With Quercetin on Plasma C-Reactive Protein Concentrations: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Mohammadi-Sartang M, Mazloom Z, Sherafatmanesh S, Ghorbani M, Firoozi D. European Journal of Clinical Nutrition. 2017;71(9):1033-1039. doi:10.1038/ejcn.2017.55.
Inhibitory Effect of Quercetin on Oxidative Endogen Enzymes: A Focus on Putative Binding Modes. Olla S, Siguri C, Fais A, et al. International Journal of Molecular Sciences. 2023;24(20):15391. doi:10.3390/ijms242015391.
Protective Effects of Quercetin on Mitochondrial Biogenesis in Experimental Traumatic Brain Injury via the Nrf2 Signaling Pathway. Li X, Wang H, Gao Y, et al. PloS One. 2016;11(10):e0164237. doi:10.1371/journal.pone.0164237.
The Multifaceted Role of Quercetin Derived From Its Mitochondrial Mechanism. Carrillo-Garmendia A, Madrigal-Perez LA, Regalado-Gonzalez C. Molecular and Cellular Biochemistry. 2024;479(8):1985-1997. doi:10.1007/s11010-023-04833-w.
The Bioavailability, Absorption, Metabolism, and Regulation of Glucolipid Metabolism Disorders by Quercetin and Its Important Glycosides: A Review. Zhu X, Ding G, Ren S, Xi J, Liu K. Food Chemistry. 2024;458:140262. doi:10.1016/j.foodchem.2024.140262.
Dietary Quercetin Supplements: Assessment of Online Product Informations and Quantitation of Quercetin in the Products by High-Performance Liquid Chromatography. Vida RG, Fittler A, Somogyi-Végh A, Poór M. Phytotherapy Research : PTR. 2019;33(7):1912-1920. doi:10.1002/ptr.6382.
Interaction of Quercetin and Its Metabolites With Warfarin: Displacement of Warfarin From Serum Albumin and Inhibition of CYP2C9 Enzyme. Poór M, Boda G, Needs PW, et al. Biomedicine & Pharmacotherapy = Biomedecine & Pharmacotherapie. 2017;88:574-581. doi:10.1016/j.biopha.2017.01.092.
Inhibitory Effects of Quercetin and Its Main Methyl, Sulfate, and Glucuronic Acid Conjugates on Cytochrome P450 Enzymes, and on OATP, BCRP and MRP2 Transporters. Mohos V, Fliszár-Nyúl E, Ungvári O, et al. Nutrients. 2020;12(8):E2306. doi:10.3390/nu12082306.
Evaluation of Inhibitory Effects of Caffeic Acid and Quercetin on Human Liver Cytochrome P450 Activities. Rastogi H, Jana S. Phytotherapy Research : PTR. 2014;28(12):1873-8. doi:10.1002/ptr.5220.
Safety Aspects of the Use of Quercetin as a Dietary Supplement. Andres S, Pevny S, Ziegenhagen R, et al. Molecular Nutrition & Food Research. 2018;62(1). doi:10.1002/mnfr.201700447.

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.

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