General

Pronunciation:
ri-fax-i-min


Trade Name(s)

  • Xifaxan
  • Zaxine Canadian Tradename

Ther. Class.
anti-infectives

Pharm. Class.
rifamycins

Indications

  • Travelers' diarrhea due to noninvasive strains of Escherichia coli.
  • Reduction in risk of overt hepatic encephalopathy recurrence.
  • Treatment of irritable bowel syndrome (IBS) with diarrhea

Action

Inhibits bacterial RNA synthesis by binding to bacterial DNA-dependent RNA polymerase.

Therapeutic Effect(s):

  • Decreased severity of travelers' diarrhea.
  • Decreased episodes of overt hepatic encephalopathy.
  • Decreased signs/symptoms of IBS

Spectrum:

Escherichia coli (enterotoxigenic and enteroaggregative strains).

Pharmacokinetics

Absorption: Poorly absorbed (<0.4%), action is primarily in GI tract.

Distribution: 80–90% concentrated in gut.

Metabolism and Excretion: Almost exclusively excreted unchanged in feces.

Half-life: 6 hr.

TIME/ACTION PROFILE

ROUTEONSETPEAKDURATION
POunknownunknownunknown

Contraindication/Precautions

Contraindicated in:

  • Hypersensitivity to rifaximin or other rifamycins;
  • Diarrhea with fever or bloody stools;
  • Diarrhea caused by other infectious agents;
  • Lactation: Potential for adverse effects in the infant. Switch to formula for duration of treatment.

Use Cautiously in:

  • OB: Use only if benefit to mother outweighs risk to fetus;
  • Pedi: Safety not established in children <18 yr (hepatic encephalopathy) or <12 yr (travelers' diarrhea).

Adverse Reactions/Side Effects

CNS: dizziness

CV: peripheral edema

GI: CLOSTRIDIUM DIFFICILE-ASSOCIATED DIARRHEA (CDAD)

* CAPITALS indicate life-threatening.
Underline indicate most frequent.

Interactions

Drug-Drug

P-glycoprotein inhibitors, including cyclosporine, may ↑ levels.

Route/Dosage

Travelers' Diarrhea

PO: (Adults and Children ≥12 yr): 200 mg 3 times daily for 3 days.

Hepatic Encephalopathy

PO: (Adults) 550 mg twice daily.

IBS with Diarrhea

PO: (Adults) 550 mg 3 times daily for 14 days; if recurrence of symptoms, may treat up to an additional 2 times.

Availability

Tablets: 200 mg, 550 mg

Assessment

  • Traveler's Diarrhea: Assess frequency and consistency of stools and bowel sounds prior to and during therapy.
  • Assess fluid and electrolyte balance and skin turgor for dehydration.
  • Hepatic Encephalopathy: Assess mental status periodically during therapy.
  • IBS with Diarrhea: Assess frequency and consistency of stools and other IBS symptoms (bloating, cramping) daily.
  • Monitor bowel function. Diarrhea, abdominal cramping, fever, and bloody stools should be reported to health care professional promptly as a sign of Clostridium difficile-associated diarrhea (CDAD). May begin up to several wk following cessation of therapy.

Lab Test Considerations:

May cause lymphocytosis, monocytosis, and neutropenia.

Potential Diagnoses

Implementation

  • Do not confuse rifaximin with rifampin.
  • PO: Administer with or without food.

Patient/Family Teaching

  • Instruct patient to take rifaximin as directed and to complete therapy, even if feeling better. Caution patient to stop taking rifaximin if diarrhea symptoms get worse, persist more than 24–48 hr, or are accompanied by fever or blood in the stool. Consult health care professional if these occur. Advise patient not to treat diarrhea without consulting health care professional. May occur up to several wk after discontinuation of medication.
  • May cause dizziness. Caution patient to avoid driving and other activities requiring alertness until response to medication is known.
  • Advise female patients to notify health care professional if pregnant or if pregnancy is suspected, or if breast feeding.

Evaluation/Desired Outcomes

  • Decreased severity of travelers' diarrhea.
  • Reduction in risk of overt hepatic encephalopathy recurrence.
  • Reduction in symptoms of IBS with diarrhea.
rifAXIMin is a sample topic from the Davis's Drug Guide.

To view other topics, please or purchase a subscription.

Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Learn more.

Citation

* When formatting your citation, note that all book, journal, and database titles should be italicized* Article titles in AMA citation format should be in sentence-case
TY - ELEC T1 - rifAXIMin ID - 51832 A1 - Quiring,Courtney, AU - Sanoski,Cynthia A, AU - Vallerand,April Hazard, BT - Davis's Drug Guide UR - https://emergency.unboundmedicine.com/emergency/view/Davis-Drug-Guide/51832/all/rifAXIMin PB - F.A. Davis Company ET - 16 DB - Emergency Central DP - Unbound Medicine ER -