• Avoid anti-motility agents until you have ruled out C. difficile or E. coli 0157:H7 as the cause.
  • Do not use bismuth subsalicylate with quinolones as binding decreases quinolone absorption.


Antibiotic therapy is NOT recommended unless symptoms severe or prolonged.


Severity criteria (one or more):

  • 6 or more diarrheal episodes per day
  • bloody diarrhea
  • persistent diarrhea (greater than 3 days)

If patient has a sepsis presentation, treat as sepsis with a GI source.

  • Culture and C. difficile toxin testing is recommended. C. difficile can be a community-associated infection and is not always associated with recent antibiotic use or hospital exposure.

Bloody diarrhea in afebrile patients should increase suspicion of E. coli 0157:H7. No antibiotic therapy recommended as it may enhance toxin release and increase risk of hemolytic uremic syndrome (HUS).

  • Consider Campylobacter spp. in persons with travel history.

Recommended Empiric Therapy (5 days)

Ciprofloxacin 500 mg PO bid
TMP/SMX 1 DS tab PO bid

If travel history and suspicion of Campylobacter spp.

Clarithromycin 500 mg PO BID, OR Erythromycin 500 mg PO QID
Ciprofloxacin 500 mg PO bid