Randomized controlled trial of probiotic use for post-colonoscopy symptoms

Symptoms of bloating, discomfort and altered bowel function persist post-colonoscopy in up to 20% of patients. A previous randomized controlled trial of probiotics for post-colonoscopy symptoms has demonstrated a reduction in duration of pain with the use of probiotics. This was performed with air insufflation and the question was asked whether the effect would persist with the use of carbon dioxide to insufflate the colon.

Eligible patients were recruited and randomized to receive either probiotic or placebo capsules post colonoscopy. A questionnaire was completed documenting the presence of pre-procedural and post-procedural symptoms for the following 2 weeks. The results were entered into a database and processed by an independent statistician. The primary outcome was mean pain score and incidence of bloating over the first 7 days and at 14 days post procedure. The secondary outcome was the time to return of normal bowel function.

Two hundred and forty participants were recruited and randomized (120 probiotic and 120 placebo). Data were available for 75 patients in the probiotic and 75 in the placebo group. There was no significant difference between groups in post-procedural discomfort, bloating nor time to return of normal bowel function. Subgroup analysis of the patients with preexisting symptoms showed a reduction in incidence of bloating with the use of probiotics.

There may be a role for the use of probiotics in the subgroup of patients with preexisting symptoms; however, routine use of probiotics to ameliorate post-procedural symptoms of carbon dioxide insufflation colonoscopy cannot be advocated.