The gut-brain axis is a two-way communication system, which explains how through the vagus nerve, the gut microbiota can affect the central nervous system (CNS), including brain functions related to the ENS, as well as how CNS can alter various gut secretions and immune responses. As a result, this dysbiosis or alteration in gut microbiota can be an early sign of PD with reported changes in short chain fatty acids, bile acids, and lipids. This gave rise to the use of probiotics and faecal microbiota transplantation as alternative approaches to improve the symptoms of patients with PD. The aim of this review is to discuss investigations that have been done to explore the gastrointestinal involvement in Parkinson’s disease, the effect of dysbiosis, and potential therapeutic strategies for PD. CLICK TO REVIEW