Last update
4/18/2026
Reviewed By
Overview
SCIENTIFIC SCORE
Moderately Effective
Based on 6 Researches
8.5
USERS' SCORE
Moderately Good
Based on 7 Reviews
7.6
Supplement Facts
Serving Size: 1 Vegetarian capsule
Amount Per Serving
%DV
Bio-Quercetin® Proprietary Blend providing 35% quercetin (10 mg) [from Japanese sophora concentrate flower bud)], 30% galactomannans (8 mg) [from fenugreek (seed)]
30 mg
**
Top Medical Research Studies
9
Quercetin reduces sinus inflammation
This study explored how quercetin may help reduce inflammation associated with sinusitis using a rat model. We observed that introducing lipopolysaccharides (LPS) caused significant inflammation in nasal and sinus areas, as well as in the lungs and brain.
When we administered quercetin after the LPS treatment, it notably decreased inflammatory markers like TNF-α and IL-6. The results indicated reduced inflammation in nasal and lung tissues, showcasing quercetin's potential benefits. However, while there were encouraging findings, its effects on brain inflammation were more limited.
When we administered quercetin after the LPS treatment, it notably decreased inflammatory markers like TNF-α and IL-6. The results indicated reduced inflammation in nasal and lung tissues, showcasing quercetin's potential benefits. However, while there were encouraging findings, its effects on brain inflammation were more limited.
Read More
9
Quercetin reduces chronic sinusitis via TLR2-NF-κB inhibition
Researchers explored how quercetin, a natural plant compound, might help prevent chronic rhinosinusitis (CRS)—a condition involving persistent nasal inflammation and tissue damage. Using both lab-grown nasal cells and mice with CRS, we found that quercetin significantly reduced inflammatory responses triggered by bacterial toxins and blocked harmful tissue remodeling processes.
The compound worked by shutting down a key inflammatory pathway called TLR2-NF-κB. Quercetin also restored balance to immune cells that had become skewed in CRS, bringing Treg and Th17 levels back into harmony. When researchers artificially reactivated this pathway, quercetin's protective effects disappeared—confirming this mechanism was essential. These results suggest quercetin could become a promising treatment for people struggling with chronic sinusitis.
The compound worked by shutting down a key inflammatory pathway called TLR2-NF-κB. Quercetin also restored balance to immune cells that had become skewed in CRS, bringing Treg and Th17 levels back into harmony. When researchers artificially reactivated this pathway, quercetin's protective effects disappeared—confirming this mechanism was essential. These results suggest quercetin could become a promising treatment for people struggling with chronic sinusitis.
Read More
9
Quercetin reduces sinusitis through inflammation inhibition
We investigated whether quercetin, a natural plant compound, could help treat chronic rhinosinusitis without nasal polyps (CRSsNP)—a widespread inflammatory condition affecting the sinuses. Using a mouse model of the disease, we found that quercetin dose-dependently reduced allergic symptoms like sneezing and nasal itching while restoring normal nasal tissue structure.
Quercetin worked by suppressing inflammation-causing proteins (IL-1β, IL-6, and IL-4) and blocking a specific cellular pathway called XBP1/HIF-1α/wnt-β-catenin that drives tissue damage. Lab tests with human nasal cells confirmed that quercetin prevented harmful cell death and restored cell growth that the disease had suppressed. These findings suggest quercetin could be a promising natural treatment for chronic sinusitis.
Quercetin worked by suppressing inflammation-causing proteins (IL-1β, IL-6, and IL-4) and blocking a specific cellular pathway called XBP1/HIF-1α/wnt-β-catenin that drives tissue damage. Lab tests with human nasal cells confirmed that quercetin prevented harmful cell death and restored cell growth that the disease had suppressed. These findings suggest quercetin could be a promising natural treatment for chronic sinusitis.
Read More
Most Useful Reviews
10
Doctor consultation advised
This product provides wonderful support for sinusitis, high blood pressure, and cholesterol issues. I recommend consulting a doctor before use.
Read More
2
Expensive alternative
2 people found this helpful
Disappointingly, after switching to this product from another Quercetin supplement with Bromelain that recommended a dosage of 500-1000 mg twice daily, I encountered severe sinusitis within days. The previous supplement effectively kept my sinus problems at bay. Unfortunately, even after tripling the dosage here, which made it costly, I only saw improvement. I will return to the original product.
Read More
9
Effective support
This product helps immensely with my sinusitis, showing better results than serrapeptase. I felt notable advancements in my condition.
Read More
Medical Researches
SCIENTIFIC SCORE
Moderately Effective
Based on 6 Researches
8.5
- All Researches
9
Quercetin reduces sinus inflammation
This study explored how quercetin may help reduce inflammation associated with sinusitis using a rat model. We observed that introducing lipopolysaccharides (LPS) caused significant inflammation in nasal and sinus areas, as well as in the lungs and brain.
When we administered quercetin after the LPS treatment, it notably decreased inflammatory markers like TNF-α and IL-6. The results indicated reduced inflammation in nasal and lung tissues, showcasing quercetin's potential benefits. However, while there were encouraging findings, its effects on brain inflammation were more limited.
When we administered quercetin after the LPS treatment, it notably decreased inflammatory markers like TNF-α and IL-6. The results indicated reduced inflammation in nasal and lung tissues, showcasing quercetin's potential benefits. However, while there were encouraging findings, its effects on brain inflammation were more limited.
Read More
9
Quercetin reduces chronic sinusitis via TLR2-NF-κB inhibition
Researchers explored how quercetin, a natural plant compound, might help prevent chronic rhinosinusitis (CRS)—a condition involving persistent nasal inflammation and tissue damage. Using both lab-grown nasal cells and mice with CRS, we found that quercetin significantly reduced inflammatory responses triggered by bacterial toxins and blocked harmful tissue remodeling processes.
The compound worked by shutting down a key inflammatory pathway called TLR2-NF-κB. Quercetin also restored balance to immune cells that had become skewed in CRS, bringing Treg and Th17 levels back into harmony. When researchers artificially reactivated this pathway, quercetin's protective effects disappeared—confirming this mechanism was essential. These results suggest quercetin could become a promising treatment for people struggling with chronic sinusitis.
The compound worked by shutting down a key inflammatory pathway called TLR2-NF-κB. Quercetin also restored balance to immune cells that had become skewed in CRS, bringing Treg and Th17 levels back into harmony. When researchers artificially reactivated this pathway, quercetin's protective effects disappeared—confirming this mechanism was essential. These results suggest quercetin could become a promising treatment for people struggling with chronic sinusitis.
Read More
9
Quercetin reduces immune-driven sinusitis progression
Researchers explored quercetin's potential to treat chronic rhinosinusitis with nasal polyps (CRSwNP) by examining how it affects immune cell behavior and tissue changes. The study found that quercetin reduced the activity of M2 macrophages—immune cells that promote inflammation and tissue remodeling—by blocking a molecular pathway called JAK2/STAT3.
In laboratory tests, quercetin prevented nasal cells from undergoing harmful changes when exposed to these inflamed macrophages. In mice with CRSwNP, quercetin treatment reduced nasal symptoms, polyp formation, and inflammation while restoring normal tissue structure. These findings suggest quercetin could become a natural therapeutic option for managing this chronic respiratory condition.
In laboratory tests, quercetin prevented nasal cells from undergoing harmful changes when exposed to these inflamed macrophages. In mice with CRSwNP, quercetin treatment reduced nasal symptoms, polyp formation, and inflammation while restoring normal tissue structure. These findings suggest quercetin could become a natural therapeutic option for managing this chronic respiratory condition.
Read More
9
Quercetin reduces sinusitis through inflammation inhibition
We investigated whether quercetin, a natural plant compound, could help treat chronic rhinosinusitis without nasal polyps (CRSsNP)—a widespread inflammatory condition affecting the sinuses. Using a mouse model of the disease, we found that quercetin dose-dependently reduced allergic symptoms like sneezing and nasal itching while restoring normal nasal tissue structure.
Quercetin worked by suppressing inflammation-causing proteins (IL-1β, IL-6, and IL-4) and blocking a specific cellular pathway called XBP1/HIF-1α/wnt-β-catenin that drives tissue damage. Lab tests with human nasal cells confirmed that quercetin prevented harmful cell death and restored cell growth that the disease had suppressed. These findings suggest quercetin could be a promising natural treatment for chronic sinusitis.
Quercetin worked by suppressing inflammation-causing proteins (IL-1β, IL-6, and IL-4) and blocking a specific cellular pathway called XBP1/HIF-1α/wnt-β-catenin that drives tissue damage. Lab tests with human nasal cells confirmed that quercetin prevented harmful cell death and restored cell growth that the disease had suppressed. These findings suggest quercetin could be a promising natural treatment for chronic sinusitis.
Read More
8
Quercetin enhances mucus transport
We explored how quercetin might help sinusitis by boosting chloride secretion and improving ciliary beat frequency in cultured sinonasal cells. In our analysis, this compound showed notable ability to enhance these functions, suggesting it could promote better mucus clearance from the sinuses.
The study involved primary cultures of human and murine sinonasal epithelial cells and demonstrated quercetin's effectiveness in increasing chloride transport. This implies potential therapeutic benefits for individuals suffering from chronic rhinosinusitis.
The study involved primary cultures of human and murine sinonasal epithelial cells and demonstrated quercetin's effectiveness in increasing chloride transport. This implies potential therapeutic benefits for individuals suffering from chronic rhinosinusitis.
Read More
User Reviews
USERS' SCORE
Moderately Good
Based on 7 Reviews
7.6
- All Reviews
- Positive Reviews
- Negative Reviews
10
Doctor consultation advised
This product provides wonderful support for sinusitis, high blood pressure, and cholesterol issues. I recommend consulting a doctor before use.
Read More
2
Expensive alternative
2 people found this helpful
Disappointingly, after switching to this product from another Quercetin supplement with Bromelain that recommended a dosage of 500-1000 mg twice daily, I encountered severe sinusitis within days. The previous supplement effectively kept my sinus problems at bay. Unfortunately, even after tripling the dosage here, which made it costly, I only saw improvement. I will return to the original product.
Read More
9
Effective support
This product helps immensely with my sinusitis, showing better results than serrapeptase. I felt notable advancements in my condition.
Read More
7.5
Allergy assistance
I find Quercetin beneficial for its supposed senolytic properties, though hard to quantify. It helps significantly with my allergies and chronic sinusitis when combined with Spirulina. The quality of this extract from Life Extension is superb.
Read More
2
Ineffective product
Unfortunately, this product did not alleviate my sinusitis.
Read More
Frequently Asked Questions
7.5
Faster recovery
My daughter's recovery from sinusitis improved significantly. This product acted as a strong support for her nasal mucosa, speeding up her healing process.
2
Expensive alternative
2 people found this helpful
Disappointingly, after switching to this product from another Quercetin supplement with Bromelain that recommended a dosage of 500-1000 mg twice daily, I encountered severe sinusitis within days. The previous supplement effectively kept my sinus problems at bay. Unfortunately, even after tripling the dosage here, which made it costly, I only saw improvement. I will return to the original product.
9
Effective support
This product helps immensely with my sinusitis, showing better results than serrapeptase. I felt notable advancements in my condition.
10
Doctor consultation advised
This product provides wonderful support for sinusitis, high blood pressure, and cholesterol issues. I recommend consulting a doctor before use.
7.5
Asthma relief
1 people found this helpful
Suffering from asthma and allergic rhinitis, I noticed significant improvement in my symptoms after using this product. However, my rhinitis worsened with persistent nasal congestion and sinusitis. After a month of antibiotics, I felt relief when the phlegm disappeared as well.
2
Ineffective product
Unfortunately, this product did not alleviate my sinusitis.
7.5
Allergy assistance
I find Quercetin beneficial for its supposed senolytic properties, though hard to quantify. It helps significantly with my allergies and chronic sinusitis when combined with Spirulina. The quality of this extract from Life Extension is superb.
9
Quercetin reduces sinus inflammation
This study explored how quercetin may help reduce inflammation associated with sinusitis using a rat model. We observed that introducing lipopolysaccharides (LPS) caused significant inflammation in nasal and sinus areas, as well as in the lungs and brain.
When we administered quercetin after the LPS treatment, it notably decreased inflammatory markers like TNF-α and IL-6. The results indicated reduced inflammation in nasal and lung tissues, showcasing quercetin's potential benefits. However, while there were encouraging findings, its effects on brain inflammation were more limited.
When we administered quercetin after the LPS treatment, it notably decreased inflammatory markers like TNF-α and IL-6. The results indicated reduced inflammation in nasal and lung tissues, showcasing quercetin's potential benefits. However, while there were encouraging findings, its effects on brain inflammation were more limited.
8
Quercetin enhances mucus transport
We explored how quercetin might help sinusitis by boosting chloride secretion and improving ciliary beat frequency in cultured sinonasal cells. In our analysis, this compound showed notable ability to enhance these functions, suggesting it could promote better mucus clearance from the sinuses.
The study involved primary cultures of human and murine sinonasal epithelial cells and demonstrated quercetin's effectiveness in increasing chloride transport. This implies potential therapeutic benefits for individuals suffering from chronic rhinosinusitis.
The study involved primary cultures of human and murine sinonasal epithelial cells and demonstrated quercetin's effectiveness in increasing chloride transport. This implies potential therapeutic benefits for individuals suffering from chronic rhinosinusitis.
7
We explored how quercetin affects sinusitis by examining its impact on human mast cells. Specifically, we focused on the expression of inflammatory cytokines after stimulating the cells.
Quercetin showed promise by reducing the gene expression and production of key inflammatory signals like TNF-alpha and IL-6. It did this by dampening the activation of NF-kappaB and p38 MAPK pathways, both crucial for inflammation.
This suggests that quercetin may be beneficial for managing conditions like sinusitis linked to mast cell activity.
Quercetin showed promise by reducing the gene expression and production of key inflammatory signals like TNF-alpha and IL-6. It did this by dampening the activation of NF-kappaB and p38 MAPK pathways, both crucial for inflammation.
This suggests that quercetin may be beneficial for managing conditions like sinusitis linked to mast cell activity.
References
- Tiboc-Schnell CN, Filip GA, Man SC, Decea N, Moldovan R, et al. Quercetin attenuates naso-sinusal inflammation and inflammatory response in lungs and brain on an experimental model of acute rhinosinusitis in rats. J Physiol Pharmacol. 2020;71. 10.26402/jpp.2020.4.03
- Zhang S, Smith N, Schuster D, Azbell C, Sorscher EJ, et al. Quercetin increases cystic fibrosis transmembrane conductance regulator-mediated chloride transport and ciliary beat frequency: therapeutic implications for chronic rhinosinusitis. Am J Rhinol Allergy. 2011;25:307. 10.2500/ajra.2011.25.3643
- Min YD, Choi CH, Bark H, Son HY, Park HH, et al. Quercetin inhibits expression of inflammatory cytokines through attenuation of NF-kappaB and p38 MAPK in HMC-1 human mast cell line. Inflamm Res. 2007;56:210. PubMed
- Qu X, Tao P, Dong J, Meng L. Quercetin alleviates the progression of chronic rhinosinusitis by affecting nasal mucosal epithelial remodeling, inflammation, and Treg/Th17 imbalance. Biochem Cell Biol. 2025;103:1. 10.1139/bcb-2025-0049
- Qu X, Tao P, Dong J, Meng L. Quercetin attenuates the progression of chronic rhinosinusitis with nasal polyps by regulating macrophage M2 polarization and remodeling of nasal mucosa. Int Immunopharmacol. 2025;162:115120. 10.1016/j.intimp.2025.115120
- Meng L, Qu X, Tao P, Dong J, Guo R. Quercetin Alleviates the Progression of Chronic Rhinosinusitis Without Nasal Polyps by Inhibiting Nasal Mucosal Inflammation and Epithelial Apoptosis. Mol Biotechnol. 2025;67:3532. 10.1007/s12033-024-01269-5
