Slow transit constipation associated with excess methane production and its improvement following rifaximin therapy: a case report.

Constipation, a common problem in gastroenterology practice, may result from slow colonic transit. Therapeutic options for slow transit constipations are limited. Excessive methane production by the methanogenic gut flora, which is more often found in patients with constipation, slows colonic transit. Thus, reduction in methane production with antibiotic treatment directed against methanogenic flora of the gut may accelerate colonic transit resulting in improvement in constipation. However, there is not much data to prove this hypothesis. We, therefore, report a patient with slow transit constipation associated with high methane production both in fasting state and after ingestion of glucose, whose constipation improved after treatment with non-absorbable antibiotic, rifaximin, which reduced breath methane values.