SIBO And Parkinson’s disease

SIBO And Parkinson's disease

SIBO And Parkinson’s disease

Before we start, other blogs that you might be interested in, include:

Numerous studies have detailed the presence of oropharyngeal, esophageal, gastric, colonic, and anorectal abnormalities in PD, but the small intestine has received exceedingly little attention, which has left it as virtually uncharted territory with regard to the presence, nature, degree, and consequences of involvement and dysfunction in PD (3).

SIBO And Parkinson’s Disease

Recent studies reported high prevalence of SIBO (small intestine bacterial overgrowth in Parkinson’s, ranging from 54% to 67%. (1)

Parkinson’s has been associated with gastroparesis and impaired gut motility which may predispose to SIBO.

In the study by Fasano et al, the presence of SIBO reported in 54% of PD subjects, was associated not only with the gut symptoms but also with motor symptoms. Interestingly, the researchers found that there was improvement in motor fluctuations following treatment with the antibiotic, rifaximin.

In another study SIBO was detected in 25% of PD patients and occurred early in the disease course. According to that report, SIBO was not associated with worse gut function, but independently predisposed to worse motor function.

How Would SIBO Cause Parkinson’s?

It is possible that SIBO contributes to motor dysfunction by disrupting small intestinal integrity leading to immune stimulation and/or alteration in L-dopa absorption. SIBO may cause changes in the gut permeability which promote translocation of bacteria and toxins across the gut lining, inducing the pro-inflammatory response (1).[/vc_column_text]


The impact of SIBO on motor function in Parkinson’s

This is the largest study to date on SIBO in PD. SIBO was detected in one quarter of patients, including patients recently diagnosed with the disease. SIBO was not associated with worse gastrointestinal symptoms, but independently predicted worse motor function. Properly designed treatment trials are needed to confirm a causal link between SIBO and worse motor function in PD (4).

Gut Motility And Parkinson’s Disease

Motility disorders of the GI tract are found frequently in patients with PD and treating the underlying GI disorders caused by PD with various prokinetics and laxatives is paramount in achieving improvements in patient’s motor function (1).

What Is The Prevalence Of SIBO In Parkinson’s?

In a systematic review and meta-analysis of the evidence, the prevalence of SIBO was 52% among patients from Western countries and 33% among patients from Eastern countries (5).

Conclusions: SIBO And Parkinson’s disease: Cause Or Consequence?

In conclusion, our meta-analysis found a strong association between SIBO and PD with approximately half of PD patients testing positive for SIBO (5).

These findings, thus, provide yet another potential route of therapeutic exploration for clinicians when patients are experiencing difficult-to-manage motor fluctuations. The growing recognition that GI dysfunction, now including both gastroparesis and SIBO, may be responsible for at least some portion of motor fluctuations also suggests that movement disorders neurologists might do well to cultivate a working relationship with a gastroenterologist who is interested in motility disorders. In fact, successful treatment of these GI aspects of PD may obviate, or at least delay, the need for more invasive medical and neurosurgical treatment approaches for motor fluctuations in some individuals with PD (3).


  1. The treatment of gastroparesis, constipation and small intestinal bacterial overgrowth syndrome in patients with Parkinson’s disease (click here)
  2. The gut-brain axis and Parkinson disease: clinical and pathogenetic relevance (click here)
  3. Beyond here be dragons: SIBO in Parkinson’s disease (click here)
  4. Small intestinal bacterial overgrowth in Parkinson’s disease (click here)
  5. Association of small intestinal bacterial overgrowth with Parkinson’s disease: a systematic review and meta-analysis (click here)
  6. Prevalence of small intestinal bacterial overgrowth in Chinese patients with Parkinson’s disease (click here)
  7. Gastrointestinal dysfunction in Parkinson’s disease (click here)
Alex Manos Profile 2015 AM Logo scaled

Alex is a certified Functional Medicine Practitioner (IFMCP) and has a MSc in Personalised Nutrition. He is also a breathwork facilitator with a background in personal training and massage therapy. He also runs The Resiliency Program - a 24 week program aimed at building physical, mental, emotional, and spiritual resilience.

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