Profile of rifaximin and its potential in the treatment of irritable bowel syndrome

Figures & data

Table 1 Studies of rifaximin in patients with IBS

Study and design	No of participants	Primary and secondary outcomes	Rifaximin dose and duration	Results	Limitations
Sharara et al^Citation36 P, R, DB, PC	N=124 Rifaximin =63 Placebo =61	Primary: global IBS symptom improvement Secondary: change in LHBT, composite 10-day symptom score	400 mg bid for 10 days	Higher global improvement in IBS symptoms with rifaximin (41.3% vs 22.9%, P=0.03). Lower mean symptoms score and bloating with rifaximin (P=0.01). No significant change in LHBT overall with rifaximin. Significant drop in LHBT in responders to rifaximin vs non-responders, and correlated with bloating and overall symptom scores (P=0.01)	Only 54% and 59% of participants in each group fulfilled Rome II criteria for IBS; single center
Pimentel et al^Citation50 P, R, DB, PC	N=87 Rifaximin =43 Placebo =44	Primary: global IBS symptoms Secondary: abdominal pain, bloating, diarrhea, and constipation	400 mg tid for 10 days	Higher global improvement in IBS symptoms with rifaximin (36.4% vs 21%, P=0.02). Bloating improved with rifaximin (P=0.01). Abdominal pain, diarrhea, and constipation were not significantly different	Most patients were from a single center; short duration
Meyrat et al^Citation15 P	N=106	LHBT Overall well-being, bloating, diarrhea, flatulence, and abdominal pain	200 mg qid for 14 days	71% were LHBT positive Improved overall well-being (3.9% vs 2.7%, P<0.001), bloating (5.5% vs 3.6%, P<0.001), flatulence (5% vs 4%, P=0.015), diarrhea (2.9% vs 2%, P=0.005), and abdominal pain (4.8% vs 3.3%, P<0.001)	Lack of control group; unblinded
Pimentel et al^Citation37 P, R, DB, PC	N=1,260 TARGET 1: Rifaximin =309 and placebo =314 TARGET 2: Rifaximin =316 and placebo =321	Primary: global IBS symptom relief for at least 2 of 4 weeks Secondary: adequate relief of bloating, abdominal pain, and discomfort	550 mg tid for 14 days	Higher global improvement in IBS symptoms with rifaximin (40.8% vs 31.2%, P=0.01, TARGET 1; 40.6% vs 32.2%, P=0.03, TARGET 2; and 40.7% vs 31.7%, P<0.001, combined). Rifaximin group had more relief of bloating (39.5% vs 28.7%, P=0.005, TARGET 1; 41.0% vs 31.9%, P=0.02, TARGET 2; and 40.2% vs 30.3%, P<0.001, combined) and abdominal pain/discomfort (44.3% vs 36.3%, P=0.03, TARGET 1 and 42.9% vs 34.4%, P=0.02, TARGET 2)	Only included IBS without constipation
Pimentel et al^Citation38 P, R, DB, PC	N=31 Neomycin =16 Neomycin and rifaximin =15	Primary: constipation severity Secondary: overall constipation severity, straining, bloating, and abdominal pain	Neomycin (500 mg bid) + placebo Neomycin 500 mg bid and rifaximin (550 mg tid) for 14 days	Lower constipation severity with addition of rifaximin (28.6 mm vs 61.2 mm, P=0.0042). Greater improvement in straining (P=0.017) and bloating (P=0.020), but not abdominal pain	IBS-C only; combined systemic and non-absorbable antibiotics

Abbreviations: IBS, irritable bowel syndrome; No, number; P, prospective; R, randomized; DB, double blind; PC, placebo controlled; LHBT, lactulose hydrogen breath test; bid, twice daily; tid, three times a day; qid, four times a day; TARGET, targeted, nonsystemic antibiotic rifaximin gut-selective evaluation of treatment for non-c irritable bowel syndrome; IBS-C, constipation-predominant IBS.

Figure 1 Percentage of patients with relief of symptoms during the primary evaluation period (weeks 3–6).

Note: Rifaximin 550 mg or placebo three times daily.
Abbreviation: IBS, irritable bowel syndrome.

ShararaAIAounEAbdul-BakiHMounzerRSidaniSElhajjIA randomized double-blind placebo-controlled trial of rifaximin in patients with abdominal bloating and flatulenceAm J Gastroenterol2006101232633316454838

 PubMed Web of Science ®Google Scholar

PimentelMParkSMirochaJKaneSVKongYThe effect of a nonabsorbed oral antibiotic (rifaximin) on the symptoms of the irritable bowel syndrome: a randomized trialAnn Intern Med2006145855756317043337

 PubMed Web of Science ®Google Scholar

MeyratPSafroneevaESchoepferAMRifaximin treatment for the irritable bowel syndrome with a positive lactulose hydrogen breath test improves symptoms for at least 3 monthsAliment Pharmacol Ther20123611–121084109323066911

 PubMed Web of Science ®Google Scholar

PimentelMLemboACheyWDRifaximin therapy for patients with irritable bowel syndrome without constipationN Engl J Med20113641223221208106

 PubMed Web of Science ®Google Scholar

PimentelMChangCChuaKSAntibiotic treatment of constipation-predominant irritable bowel syndromeDig Dis Sci20145961278128524788320

 PubMed Web of Science ®Google Scholar