Rifamycin

Indications

Rifamycin is used for: Traveler’s Diarrhea

Adult Dose

Traveler’s Diarrhea Minimally absorbed antibiotic indicated for traveler’s diarrhea caused by noninvasive strains of Escherichia coli, not complicated by fever or blood in the stool 388 mg (2 tablets) PO BID x 3 days Hepatic impairment: Not studied; no dosage adjustment required owing to minimal systemic absorption

Child Dose

<18 years: Safety and efficacy not established

Renal Dose

Renal impairment: Not studied; no dosage adjustment required owing to minimal systemic absorption

Administration

Take each dose with full glass of liquid (6-8 oz) Do not take concomitantly with alcohol May take with or without food

Contra Indications

Known hypersensitivity to rifamycin or any of the other rifamycin-class antimicrobial agents

Precautions

Not effective for diarrhea complicated by fever and/or bloody stool; discontinue use if diarrhea gets worse or persists >48 hr; consider alternative antibacterial therapy Consider Clostridium difficile-associated diarrhea (CDAD) in all patients who present with diarrhea following antibacterial drug use; CDAD can occur over 2 months after antibiotic discontinued Prescribing rifamycin without proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria Owing to minimal systemic rifamycin concentrations observed, clinically relevant drug interactions are not expected

Pregnancy-Lactation

Pregnancy There are no available data regarding use in pregnant women Systemic absorption in humans is negligible following PO administration; not expected that maternal use results in fetal exposure Lactation There are no available data regarding presence in human milk Systemic absorption in humans is negligible following PO administration; exposure to breastfed infants through breastmilk is expected to be negligible The development and health benefits of breastfeeding should be considered along with the mother’s clinical need for the drug and any potential adverse effects on the breastfed child or from the underlying maternal condition

Interactions

Adverse Effects

Side effects of Rifamycin : 1-10% Constipation (3.5%) Headache (3.3%) Dyspepsia (<2%)

Mechanism of Action

Oral nonabsorbable antibiotic that can be used for the treatment of bacterial infections of the colon Belongs to the ansamycin antibacterial drug class and acts by inhibiting the beta-subunit of bacterial DNA-dependent RNA polymerase, blocking 1 of the DNA transcription steps; this results in bacterial synthesis inhibition and consequently bacterial growth