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Medically reviewed by Last updated on Aug 13, 2020.


(RIF a MYE sin)

Index Terms

  • Aemcolo
  • Rifamycin sodium

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Tablet Delayed Release, Oral:

Aemcolo: 194 mg

Brand Names: U.S.

  • Aemcolo

Pharmacologic Category

  • Rifamycin


Rifamycin inhibits bacterial synthesis by inhibiting the beta-subunit of the bacterial DNA-dependent RNA polymerase.


Feces: 86%

Protein Binding


Use: Labeled Indications

Travelers’ diarrhea: Treatment of travelers’ diarrhea (TD) caused by noninvasive strains of Escherichia coli in adults

Limitations of use: Rifamycin is not indicated in patients with diarrhea complicated by fever or bloody stool or due to pathogens other than noninvasive strains of E. coli.


Hypersensitivity to rifamycin, other rifamycin class antimicrobial agents (eg, rifaximin), or any component of the formulation.

Dosing: Adult

Travelers' diarrhea: Oral: 388 mg twice daily for 3 days

Dosing: Geriatric

Refer to adult dosing.


Oral: Administer each dose with a 6 to 8 ounce glass of liquid (not alcohol), with or without food. Swallow tablets whole; do not crush, break, or chew.

Bariatric surgery: Tablet, delayed release: Some institutions may have specific protocols that conflict with these recommendations; refer to institutional protocols as appropriate. No alternative formulation is available. If safety and efficacy can be effectively monitored, no change in formulation or administration is required after bariatric surgery.


Store at 20°C to 25°C (68°F to 77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).

Drug Interactions

Cholera Vaccine: Antibiotics may diminish the therapeutic effect of Cholera Vaccine. Management: Avoid cholera vaccine in patients receiving systemic antibiotics, and within 14 days following the use of oral or parenteral antibiotics. Avoid combination

Sodium Picosulfate: Antibiotics may diminish the therapeutic effect of Sodium Picosulfate. Management: Consider using an alternative product for bowel cleansing prior to a colonoscopy in patients who have recently used or are concurrently using an antibiotic. Consider therapy modification

Typhoid Vaccine: Antibiotics may diminish the therapeutic effect of Typhoid Vaccine. Only the live attenuated Ty21a strain is affected. Management: Avoid use of live attenuated typhoid vaccine (Ty21a) in patients being treated with systemic antibacterial agents. Postpone vaccination until 3 days after cessation of antibiotics and avoid starting antibiotics within 3 days of last vaccine dose. Consider therapy modification

Adverse Reactions

The following adverse drug reactions and incidences are derived from product labeling unless otherwise specified.

1% to 10%:

Central nervous system: Headache (3%)

Gastrointestinal: Constipation (4%), dyspepsia (<2%)

Frequency not defined:

Gastrointestinal: Abdominal pain

Miscellaneous: Fever


Concerns related to adverse effects:

• Superinfection: Prolonged use may result in bacterial superinfection, including C. difficile infection (CDI); CDI has been observed >2 months postantibiotic treatment.

Other warnings/precautions:

• Appropriate use: Not shown to be effective in patients with diarrhea complicated by fever and/or bloody stool; when these patients were treated with rifamycin, they had prolonged time to last unformed stool. Effectiveness has not been demonstrated in patients with travelers’ diarrhea caused by pathogens other than E. coli. Discontinue treatment and consider alternative antibacterial therapy if diarrhea worsens or persists >48 hours.

Monitoring Parameters

Bloody stools, frequency of diarrhea

Pregnancy Considerations

Maternal systemic absorption is limited following oral administration, therefore exposure to the fetus is not expected.

Patient Education

What is this drug used for?

• It is used to treat travelers' diarrhea.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Headache

• Constipation

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Clostridioides (formerly Clostridium) difficile-associated diarrhea like abdominal pain or cramps, severe diarrhea or watery stools, or bloody stools.

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.