What is the recommended antibiotic dosage and duration for treating bacterial diarrhea in adults?

From the Guidelines

For bacterial diarrhea in adults, azithromycin 500 mg once daily for 3 days is the recommended empiric treatment, due to its efficacy and safety profile, as supported by the most recent and highest quality study 1. The choice of antibiotic depends on the specific pathogen, but azithromycin is preferred for Shigella or Campylobacter infections.

• The dosage and duration of treatment may vary depending on the severity of symptoms and the specific pathogen involved.
• For travelers' diarrhea, a shorter course of 1-3 days is typically sufficient.
• Supportive care with fluid replacement and electrolyte management is essential regardless of antibiotic use.
• If symptoms persist beyond 5-7 days or include high fever, bloody stools, or severe abdominal pain, medical evaluation is necessary. The most recent study 1 recommends azithromycin as the first-line agent in cases of dysentery, as well as acute watery diarrhea with greater than mild fever, due to its efficacy and safety profile.
• The study also notes that fluoroquinolones, such as ciprofloxacin, may be effective, but their use is limited by the increasing resistance of certain pathogens, such as Campylobacter spp. 1.
• Rifaximin, a nonabsorbable antibiotic, has demonstrated comparable efficacy to fluoroquinolones in non-invasive travelers' diarrhea caused by diarrheagenic E. coli, but is less effective for the treatment of invasive pathogens 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION C. difficile-associated diarrhea: Adult Patients (18 years of age or greater): 125 mg orally 4 times daily for 10 days. Staphylococcal enterocolitis: Adult Patients (18 years of age or greater): 500 mg to 2 g orally in 3 or 4 divided doses for 7 to 10 days. The recommended dose is 125 mg administered orally 4 times daily for 10 days. Total daily dosage is 500 mg to 2 g administered orally in 3 or 4 divided doses for 7 to 10 days.

The antibiotic adult dosage for bacterial diarrhea is:

• C. difficile-associated diarrhea: 125 mg orally 4 times daily
• Staphylococcal enterocolitis: 500 mg to 2 g orally in 3 or 4 divided doses The length of time for treatment is:
• C. difficile-associated diarrhea: 10 days
• Staphylococcal enterocolitis: 7 to 10 days 2, 2, 2

From the Research

Antibiotic Adult Dosage

• The dosage of antibiotics for adult patients with bacterial diarrhea is not explicitly stated in the provided studies 3, 4, 5, 6, 7.
• However, the studies mention various antibiotics that can be used to treat bacterial diarrhea, including vancomycin, metronidazole, fidaxomicin, and teicoplanin 5, 7.

Length of Time for Bacterial Diarrhea

• The length of time for bacterial diarrhea can vary depending on the cause and severity of the infection 3.
• Acute watery diarrhea typically lasts 5-10 days and is normally self-limiting 3.
• Bloody diarrhea (dysentery) and persistent diarrhea can last longer and may require specific treatment 3.
• The duration of antibiotic treatment for bacterial diarrhea is not explicitly stated in the provided studies, but it is typically given for a specific period, such as 10 days 7.

Treatment Considerations

• Antibiotic treatment should be considered for patients with severe illness, high frequency of stools, fever, bloody diarrhea, underlying immune deficiency, advanced age, or significant comorbidities 3, 4.
• The choice of antibiotic depends on the suspected cause of the infection and the patient's clinical condition 5, 7.
• Vancomycin and fidaxomicin have been shown to be effective in treating Clostridium difficile-associated diarrhea, while metronidazole is a cheaper alternative 7.
• Teicoplanin may be more effective than vancomycin, but the quality of evidence is very low 7.