Efficacy of Bacillus probiotics in prevention of antibiotic‐associated diarrhoea: a randomized, double‐blind, placebo‐controlled clinical trial

Abstract

Introduction: Antibiotic-associated diarrhoea (AAD) is one of the most common side effects of antibiotic therapy. The main mechanism associated with the development of AAD is significant changes in the composition and quantity of the gut microbiota during the treatment with antibiotics. Probiotic bacteria have been shown to stabilize the gut microbiota and can be used to prevent diarrhoea associated with antibiotic therapy. Case presentation: We present the results of a single-centre, randomized, double-blinded, placebo-controlled clinical trial. Patients were randomized into three groups: probiotic group 1 received a probiotic containing strains Bacillus subtilis 3 and Bacillus licheniformis 31; probiotic group 2 received a probiotic, containing B. subtilis 3; and the placebo group received an inert composition in vials, formulated to be indistinguishable from the vials with probiotics. Participants received one vial twice a day. Probiotic treatment significantly reduced incidents of AAD in the patients. Among 91 patients in group 1 treated with probiotic mix, nine developed AAD. In group 2, seven patients out of 90 who received only one probiotic strain developed AAD. A considerably higher incidence of AAD was registered in the placebo group – 23 from 90 patients (P,0.001 vs groups 1 and 2). Both probiotics demonstrated a significant effect in the prevention of nausea, bloating, vomiting and abdominal pain. Conclusion: Treatment with Bacillus probiotics during antibiotic therapy significantly decreased the incidence of AAD and adverse effects related to the use of antibiotics. Both probiotics were well tolerated by the patients without side effects. No significant difference was found in the efficacy of the two probiotics.