Study of the Effects and Mechanisms of Yeast Postbiotics on Persistent Allergic Rhinitis Symptoms

Participants in the intervention group will take two capsules of yeast postbiotics daily after meals, with each capsule containing 250 mg of yeast postbiotics, along with maltodextrin and silicon dioxide.

Participants in the placebo group will take an equal number of placebo capsules, identical in dosage form, taste, appearance, and packaging. The placebo contains only maltodextrin and a small amount of silicon dioxide. All participants will take two capsules once daily, swallowed with warm water after meals.