11 Comparable antimicrobial activity

was seen between rifaximin and other antimicrobials for E. coli. In addition, activity against Clostridium difficile was comparable to metronidazole and vancomycin (MIC90 = 0.005 through 2 μg/mL).10, 12 Of importance, in studies on traveler’s diarrhea, aerobic gut species return to baseline after the end of rifaximin therapy.10 Therapy with rifaximin can be associated with adverse effects that are relatively minor and rarely require reduction or discontinuation of therapy. Patients who are allergic to not only rifaximin, but also rifabutin (Mycobutin), rifampin (Rifadin, Rifamate, Rifater, Rimactane), and rifapentine (Priftin) should avoid use of rifaximin. The main gastrointestinal adverse events are flatulence, nausea, vomiting, abdominal pain, and weight loss which have been reported in ranges from 5%-17%, no different from placebo. Clostridium difficile in cirrhosis has check details a poor prognosis therefore the notion of long-term antibiotic therapy in this population does raise some concerns.13 In the Bass et al. trial, there were two cases of C. difficile in the rifaximin group but none in the placebo group. This is interesting

because rifaximin is active against C. difficile.6, 12 It is a relevant concern, specifically because of depressed immunity, frequent hospitalization and other antibiotic use in these patients.13 Additionally, if patients selleck inhibitor are on lactulose concomitantly, C. difficile diarrhea may be mistakenly attributed to lactulose, further delaying the diagnosis. Clinicians should be vigilant against C. difficile in patients

with cirrhosis MCE公司 and specifically those receiving long-term therapy such as rifaximin. Development of drug resistance is discussed in the next section. Although rifaximin has been approved for therapy in several European countries and the experience in those countries has not raised any significant concerns, the U.S. experience remains limited. The specific areas of uncertainty involve the evolving role of rifaximin as a possible first or second-line therapy, emergence of resistant strains and the possibility of clinical drug interactions. Rifaximin is currently a second-line therapy for HE in part due to the extreme cost difference between rifaximin and lactulose and also because lactulose therapy alone can prevent recurrent HE in selected patients. Also, there are only short-term studies that use rifaximin as an initial therapy for HE.10 With U.S. Food and Drug Administration (FDA) approval for this in the United States for prevention of recurrence, the current role appears to be a second-line. The role of rifaximin is evolving and it is feasible that with longer-term and head-to-head studies and with reduction in cost, it may become first-line therapy for HE.