From:  Therapeutic role of probiotics in motor and non-motor symptoms of Parkinson’s disease

 Experimental studies showing sleep parameters improvement induced by probiotic interventions in PD.

Study (year)Probiotic(s)DurationDose/PresentationSleep outcome
Human studies
Sun et al. (2022) [82]Probio-M8 (Bifidobacterium animalis subsp. lactis)3 months2 g of Probio-M8 powder (3 × 1010 CFU/day; maltodextrin as excipient) dailyImproved sleep quality on the Parkinson’s Disease Sleep Scale (PDSS) (p = 0.05).
Du et al. (2025) [97]Bacillus licheniformis, Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis12 weeksBacillus licheniformis (2.5 × 109 CFU/capsule once daily); Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis (each 1.0 × 107 CFU/capsule once daily)UPDRS scores decreased significantly in the probiotic group, p = 0.048.

PD: Parkinson’s disease; UPDRS: Unified Parkinson’s Disease Rating Scale.