Rifaximin works quicker than LFD in IBS symptom management

In the treatment of patients with irritable bowel syndrome (IBS), rifaximin is as good as the low FODMAP diet (LFD), although the drug provides faster symptom relief and is associated with higher adherence, according to a study.

A total of 100 adult patients with IBS (median age 50 years, 52 percent female) participated in the study. These patients were randomly assigned to receive treatment with rifaximin (n=50) or to follow LFD (n=50) for 4 weeks.

Composite symptom improvement (abdominal pain/discomfort and stool consistency/frequency) at week 4 was assessed as the primary outcome. Secondary outcomes included individual symptom improvement, ≥50-point reduction in IBS Symptom Severity Scale (IBS-SSS), health-related quality of life (HRQOL), Hospital Anxiety and Depression Scale (HADS), small intestinal bacterial overgrowth eradication, adherence, and adverse events.

Of the patients, 68 percent had IBS with diarrhoea and 17 percent had small intestinal bacterial overgrowth.

At week 4, composite symptom improvement occurred in 56 percent of patients in the rifaximin group and 48 percent of those in the LFD group, with the difference not reaching statistical significance (p=0.423). However, symptom improvement occurred as early as week 2 for significantly more patients in the rifaximin group, including global symptoms (90 percent vs 72 percent; p=0.022), bloating (84 percent vs 58 percent; p=0.004) and abdominal pain (80 percent vs 58 percent; p=0.017). HRQOL and anxiety scores improved in both groups.

Small intestinal bacterial overgrowth was eradicated in 63.6 percent of patients in the rifaximin group and in 50 percent of those in the LFD group. Finally, adherence was significantly better with rifaximin than with LFD (95.9 percent vs 77.8 percent; p=0.008).

None of the patients in either group experienced serious adverse events.