Obsessive-compulsive disorder is a debilitating chronic condition characterized by intrusive, ego dystonic ideas or impulses that often accompany ritualistic and time-consuming compulsions. The complex interplay between the brain and the gut, integrates neural, hormonal and immunological signalling, involving the central nervous system and the enteric nervous system. There is a distinct lack of research concerning obsessive compulsive disorder and the use of probiotics. There are very few treatment methods for Obsessive-compulsive disorder, and those that are used are less than ideal because of the potential side-effects, this is complicated by the unclear pathophysiology and aetiology of Obsessive-compulsive disorder. There is however an increasing evidence base which suggests that the gut microbiome and gut brain interaction may play an important role in the development and progression of psychiatric disorders. Potential treatment modalities that affect gut microbiome, and the gut brain interaction may be more effective means of treatment than many psychiatric illnesses which may include obsessive-compulsive disorder.