Background: In association with standard management, natural pharmaceutical standard (PS) supplements may play an important role in managing and preventing mild-to-moderate symptoms of asthma, a significant health issue that impacts patients and the healthcare system. Quercetin is a natural flavonoid with important biological properties (anti-inflammatory, antihistamine and anti-oxidative actions).
Methods: In this pilot registry, we evaluated the effects of quercetin formulated with the Phytosome® delivery system (Quercefit™, QFit)+standard management (SM) in otherwise healthy subjects with mild-moderate asthmatic attacks and rhinitis. Subjects used either QFit 1 or 2 tabs/day in association with SM or SM only (control group). After 30 days of management, we evaluated the presence of the main signs/symptoms of asthma according to the GINA classification system also considering the need of rescue medication, nasal drops, the use of inhalers, the rhinitis score and oxidative stress.
Results: QFit+SM showed superior results compared with SM alone in controlling, preventing and reducing daily and night symptoms, in maintaining higher peak expiratory flow (PEF) and in decreasing PEF variability. The supplementary use of QFit improved additional measures of asthma management, decreasing the use of inhalers, nasal drops, rescue medications and improving the rhinitis score. QFit produced a significantly more evident reduction in oxidative stress compared with SM; Qfit showed a very good safety profile.
Conclusions: This preliminary supplement, concept registry shows a potential protective and preventive effect of quercetin on attacks frequency and in controlling the most common signs/symptoms of asthma in the milder cases of the disease.