In a 30-day study of 55 people with chronic rhinitis, a nasal spray combining glycyrrhizin and mannitol reduced all four major nasal symptoms (measured by patient reports) and lowered inflammatory cells in the nasal lining. The treatment worked for both allergic and non-allergic rhinitis, though it was more effective at reducing certain immune cells in allergic cases.

Researchers gave 55 chronic rhinitis patients either glycyrrhizin and mannitol nasal spray or a control treatment for 30 days, tracking symptom improvement through patient surveys and analyzing nasal cell samples before and after.

Funding not disclosed in abstract