Synopsis

Source of validity: Scientific
Rating (out of 5): 2

Quercetin is a plant-derived flavonoid found in a variety of fruits and vegetables, and it has been studied for its potential effects on the immune system and inflammation. Its use to support or treat sinus congestion is primarily justified by emerging scientific interest rather than strong traditional use. Quercetin is known to exhibit anti-inflammatory and antioxidant properties, and some preclinical studies suggest it may have a role in stabilizing mast cells, thereby reducing the release of histamine and other inflammatory mediators that contribute to nasal congestion and sinus symptoms. A few small clinical trials and animal studies have hinted at quercetin's potential to reduce allergic symptoms, such as rhinorrhea and nasal congestion, particularly in the context of allergic rhinitis. Its proposed mechanism involves inhibition of histamine release and downregulation of pro-inflammatory cytokines. However, evidence in humans specifically targeting sinus congestion is limited, with most studies being small, short-term, or involving combination supplements rather than quercetin alone. Systematic reviews and major health authorities currently do not endorse quercetin as a primary therapy for sinus congestion due to the lack of large, high-quality clinical trials. Thus, while there is a biological rationale and some preliminary evidence, the overall scientific support is weak, and the efficacy remains unproven in rigorous clinical settings.

More about quercetin
More about Congestion (sinus)

Other ingredients used for Congestion (sinus)

Other health conditions supported by quercetin

Products containing quercetin

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