Usefulness of Lactococcus lactis Strain Plasma for Treatment of Allergic Rhinitis: Four Case Reports

Allergic rhinitis affects many people, especially due to cedar and cypress pollen in spring, for which no effective, reliable, and decisive treatment has been established. Recently, Lactococcus lactis strain Plasma, which exhibits immunostimulatory effects and regulates plasmacytoid dendritic cells, has attracted much attention. In this study, we investigated whether Lactococcus lactis strain Plasma would be effective against allergic rhinitis. To examine the possible effects, we had 4 volunteer rhinitis patients with allergies to Japanese cedar and cypress who took a drink or supplement containing 100 billion lactobacilli during the pollen season and throughout the year over the 2022 and 2023 seasons. In the 2022 season, 3 patients with mild-to-moderate symptoms no longer required anti-allergic medications. However, 2 required an anti-allergy drug in 2023, and the amount of pollen reportedly scattered was large, even though they took it year-round. The other 2 patients who had been taking Lactococcus lactis strain Plasma for the entire year or throughout the pollen season had almost no symptoms. These results suggest that Lactococcus lactis strain Plasma could have an auxiliary effect in controlling rhinitis, regardless of the amount of scattered pollen and the patient’s immune responsiveness.