rifaximin

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

Therapeutic effects:

Decreased severity of travelers' diarrhea.
Decreased episodes of overt hepatic encephalopathy.
Decreased signs/symptoms of irritable bowel syndrome with diarrhea.

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/Excretion: Almost exclusively excreted unchanged in feces.

Half-Life: 6 hr.

Time/Action Profile ⬆ ⬇

ROUTE	ONSET	PEAK	DURATION
PO	unknown	unknown	unknown

Contraind./Precautions ⬆ ⬇

Contraindicated in:

Hypersensitivity to rifaximin or other rifamycins;
Diarrhea with fever or bloody stools;
Diarrhea caused by other infectious agents;
Lactation: Lactation.

Use Cautiously in:

OB: Use during pregnancy only if potential maternal benefit justifies potential fetal risk;
Pedi: Safety not established in children <18 yr (hepatic encephalopathy or irritable bowel syndrome with diarrhea) or <12 yr (travelers' diarrhea).

Adv. Reactions/Side Effects ⬆ ⬇

CV: peripheral edema

GI: CLOSTRIDIOIDES DIFFICILE-ASSOCIATED DIARRHEA (CDAD)

Neuro: dizziness

Interactions ⬆ ⬇

Drug-drug:

P-glycoprotein inhibitors, including cyclosporine, may ↑ levels and risk of toxicity.
May cause fluctuations in INR when used with warfarin; closely monitor INR.

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.

Irritable Bowel Syndrome 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.
Irritable Bowel Syndrome With Diarrhea: Assess frequency and consistency of stools and other irritable bowel syndrome 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 CDAD. May begin up to several wk following cessation of therapy.

Lab Test Considerations:

May cause lymphocytosis, monocytosis, and neutropenia.

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.
Rep: Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

Evaluation/Desired Outcomes ⬆ ⬇

Decreased severity of travelers' diarrhea.
Reduction in risk of overt hepatic encephalopathy recurrence.
Reduction in symptoms of irritable bowel syndrome with diarrhea.

US Brand Names ⬆ ⬇

Canadian Brand Names ⬆ ⬇

Code ⬆

NDC Code

55154- Cardinal Health
- 55154-6777- XIFAXAN
  - 55154-6777-8- 360 TABLET in 1 BOTTLE, PLASTIC (55154-6777-8)

65649- Salix Pharmaceuticals, Inc.
- 65649-301- XIFAXAN
  - 65649-301-03- 30 TABLET in 1 BOTTLE (65649-301-03)

65649- Salix Pharmaceuticals, Inc.
- 65649-301- XIFAXAN
  - 65649-301-05- 10 BLISTER PACK in 1 CARTON (65649-301-05) > 10 TABLET in 1 BLISTER PACK

65649- Salix Pharmaceuticals, Inc.
- 65649-301- XIFAXAN
  - 65649-301-41- 100 TABLET in 1 BOTTLE (65649-301-41)

65649- Salix Pharmaceuticals, Inc.
- 65649-303- XIFAXAN
  - 65649-303-01- 3 CARTON in 1 TRAY (65649-303-01) > 1 BLISTER PACK in 1 CARTON > 2 TABLET in 1 BLISTER PACK

65649- Salix Pharmaceuticals, Inc.
- 65649-303- XIFAXAN
  - 65649-303-02- 60 TABLET in 1 BOTTLE (65649-303-02)

65649- Salix Pharmaceuticals, Inc.
- 65649-303- XIFAXAN
  - 65649-303-03- 6 BLISTER PACK in 1 CARTON (65649-303-03) > 10 TABLET in 1 BLISTER PACK

65649- Salix Pharmaceuticals, Inc.
- 65649-303- XIFAXAN
  - 65649-303-04- 14 BLISTER PACK in 1 CARTON (65649-303-04) > 3 TABLET in 1 BLISTER PACK

65649- Salix Pharmaceuticals, Inc.
- 65649-303- XIFAXAN
  - 65649-303-05- 3 CARTON in 1 TRAY (65649-303-05) > 1 BLISTER PACK in 1 CARTON > 3 TABLET in 1 BLISTER PACK

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Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇

Action ⬆ ⬇