The participants continued their usual treatment, and the intervention group also took probiotics daily. The probiotic species were Bacillus licheniformis, Bifidobacterium longum, Lactobacillus acidophilus, and Enterococcus faecalis.

Questionnaires were used to evaluate Parkinson’s disease symptoms and symptoms of REM sleep behavior disorder. Both outcomes improved in the probiotic group compared to the control group.

Moreover, 8 participants had a clinically significant improvement in symptoms of REM sleep behavior disorder in the probiotic group, and only 1 participant did in the control group.

Probiotics for improving symptoms of Parkinson’s disease and REM sleep behavior disorder Original paper