Supplements
quercetin treats allergic rhinitis
In plain terms: Does quercetin relieve hay fever and allergy symptoms?
Insufficient Supplements
Part of: 🧪 quercetin
RefutedContestedStrong support
consensus score 0.19
⚖️ Thin evidence — read the needle loosely. The score shows which way the studies lean, but there are too few independent, high-quality ones to place it firmly. Expect this to move as better evidence arrives.
Mostly for itchy eyes, not a blocked nose. Only three small trials exist, all using absorption-enhanced forms, and two of the three found no real benefit for nasal symptoms, the thing most people actually want relieved.
📅 Last reviewed: 2026-07-26 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: Human trials (RCT / n-of-1)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
2 support 0 contradict 0 tested null 14 mixed · 16 sources, 2 independent groups
What the evidence shows
Narrow, formulation-dependent, and weakest exactly where it matters. Only three genuine human RCTs exist, all small (n=20-66), all in Japanese cedar-pollinosis cohorts, and all using ABSORPTION-ENHANCED forms — phospholipid phytosome or EMIQ. Plain quercetin has never been tested in humans for this.
The evidence (16)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Luo M et al 2026 · study_type: in-vitro | in-vitro | mixed | low | Formulation: plain quercetin (unspecified purity), tested in human nasal epithelial cells stimulated with house-dust-mite extract in vitro, plus network-pharmacology/docking (not a human trial). Quercetin reduced HDM-induced ALOX5/LTB4 expr TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Cheng J et al 2022 · study_type: in-vitro | in-vitro | mixed | low | Formulation: plain quercetin, tested in vitro on LPS-stimulated human nasal epithelial cells (HNEpC) at 10-200 uM for 24h. Quercetin reversed LPS-induced apoptosis and inflammatory cytokine release via the miR-21/DMBT1/NF-kB axis; mechanism TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Kawai M et al 2009 · study_type: RCT | RCT | mixed | low | RCT (n=20 cedar-pollinosis patients) of EMIQ (enzymatically-modified isoquercitrin, a bioavailable quercetin-glycoside form; 100 mg BID = 200 mg/day) for 8 weeks found significantly lower ocular/ocular-itching scores (p<0.05) but nasal symp |
| Lv Z et al 2025 · study_type: animal | animal | mixed | moderate | Preclinical systematic review/meta-analysis of 13 murine/rat allergy-model studies (plain quercetin, doses/formulation not detailed) found quercetin significantly reduced IgE, histamine, eosinophil/macrophage infiltration and IL-4/TNF-α whi TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Naso M et al 2025 · study_type: observational | observational | mixed | low | Narrative review states that despite abundant in vitro/murine AR-model evidence, only TWO human trials have tested quercetin as monotherapy for allergic disease — both reported positive symptom/QoL results — and proposes a new quercetin-pho TEMPERED: narrative review whose own finding is that only TWO human trials exist — that is a statement about scarcity, not corroboration. |
| Hirano T et al 2009 · study_type: RCT | RCT | mixed | low | RCT (n=24 cedar-pollinosis patients) of EMIQ (100 mg/day) for 8 weeks, started preventatively 4 weeks pre-season, found significantly lower ocular symptom+medication scores in some weeks but explicitly NO significant difference in nasal sym |
| Otaki A et al 2023 · study_type: animal | animal | mixed | low | Formulation: plain oral quercetin, >25 mg/kg/day for 5 days, in a TDI-sensitized rat allergic-rhinitis model, plus in-vitro TNF-stimulated human nasal epithelial cells (effective only at >5.0 uM; <2.5 uM inactive). Oral quercetin raised ant TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Kang C et al 2026 · study_type: animal | animal | mixed | moderate | OVA-induced allergic-rhinitis mouse model (plain quercetin by gavage, dose not stated in abstract, dexamethasone comparator) found quercetin lowered allergic symptom scores and serum OVA-IgE/IL-4/IL-13/IL-1β/IL-17 while raising IL-10, via T TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Lai YR et al 2025 · study_type: meta-analysis | meta-analysis | mixed | low | Meta-analysis of 13 human RCTs (n=823) of polyphenolic compounds (catechins and/or quercetin, not isolated per-compound) found reduced total nasal symptom score, sneezing, and nasal itching in seasonal AR (SMD 0.5-0.75) but no significant Q |
| Kang C et al 2023 · Research Square | animal | mixed | low | Formulation: plain oral quercetin (dose not specified in abstract) vs. dexamethasone, gavage, in an OVA-induced mouse AR model; UNPUBLISHED PREPRINT, not peer-reviewed. Quercetin reduced OVA-induced allergic symptom scores and serum IgE/IL- TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Pellow J et al 2020 · study_type: observational | observational | supports | low | Mixed-methods systematic review of AR supplements (48 RCTs, 10 observational) lists isoquercitrin (a quercetin glycoside, not plain quercetin) as one of several single supplements with 'promising evidence,' and a vitamin-D3+quercetin+Perill |
| Deng Y et al 2025 · study_type: animal | animal | mixed | low | Formulation: plain isolated quercetin (QUE) vs. the Huangqi-Gancao herbal decoction (HQD); dose/route not stated in abstract; tested in an OVA-induced mouse AR model alongside network-pharmacology/docking (identified QUE as the herb pair's TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Xiao Y et al 2026 · study_type: animal | animal | mixed | moderate | OVA-induced mouse AR model plus in vitro IL-33-stimulated mast cell (RBL-2H3) assays; plain quercetin suppressed IL-33-driven degranulation/cytokine release in vitro and, in vivo, alleviated AR symptom scores, reduced Th2 cytokines/OVA-IgE/ TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Yamada S et al 2022 · study_type: RCT | RCT | supports | moderate | RCT (n=66 Japanese adults with pollinosis) of Quercetin phytosome® (phospholipid-complexed, bioavailability-enhanced formulation; 200 mg/day) for 4 weeks found significant improvement vs placebo in JRQLQ scores (eye itching, sneezing, nasal |
| Ke X et al 2023 · study_type: animal | animal | mixed | low | Formulation: plain oral quercetin, 20/35/50 mg/kg/day, in an ovalbumin-induced allergic rhinitis mouse model (duration not stated). Quercetin reduced nasal rubbing/sneezing (nasal symptoms), serum IgE/IgG1/histamine and Th17-skewed cytokine TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
| Mu D et al 2024 · study_type: animal | animal | mixed | moderate | OVA-type AR mouse model treated with quercetin-chitosan nasal nanoparticles (~229 nm, 79.6% encapsulation) — a nasal nanoparticle delivery form, not oral/systemic quercetin — significantly reduced sneezing and nasal-rubbing events and lower TEMPERED: rodent OVA/TDI model or nasal-cell assay — tests the mechanism, not human symptom relief, which is what this claim asserts. |
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