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Treatment for Infectious Gastroenteritis*

Treatment for Infectious Gastroenteritis*

Organism

Antibiotic (or Other Therapy)

Campylobacter jejuni

Azithromycin

Ciprofloxacin †

Cholera (Vibrio cholerae) ‡

Ciprofloxacin

Doxycycline §

Azithromycin

Clostridioides difficile

Fidaxomicin

Vancomycin

Metronidazole ‖

Monoclonal antibodies (for severe infection, to prevent recurrence)

Fecal microbial transplant

Entamoeba histolytica

Metronidazole

Tinidazole

Giardia intestinalis (G. lamblia)

Tinidazole

Metronidazole

Nitazoxanide

Shigella

Ciprofloxacin

Azithromycin

* Antibiotics are not indicated in most cases but may be used supportively with IV fluids to treat infections caused by specific organisms.

† Resistance is increasing.

‡ Antibiotic selection should be guided by susceptibility testing when available because resistance to doxycycline, fluoroquinolones, and sulfamethoxazole/trimethoprim (SMX/TMP) is increasing in certain areas and strains. In general, doxycycline is the recommended first-line antibiotic for non-pregnant adults. Azithromycin is first-line for children and pregnant women and second-line for others. Other recommendations vary, but SMX/TMP is generally a second-line antibiotic for children if the strain in an outbreak is susceptible. Ciprofloxacin is second- or third-line in non-pregnant adults and, although generally avoided in children, can be used as second-line if strains are resistant to SMX/TMP.

§ This antibiotic should not be given to pregnant women.

‖ Metronidazole is not recommended but may be used in patients intolerant of vancomycin and fidaxomicin.

¶ Treatment should be followed by a course of iodoquinol for 20 days or paromomycin for 7 days.

* Antibiotics are not indicated in most cases but may be used supportively with IV fluids to treat infections caused by specific organisms.

† Resistance is increasing.

‡ Antibiotic selection should be guided by susceptibility testing when available because resistance to doxycycline, fluoroquinolones, and sulfamethoxazole/trimethoprim (SMX/TMP) is increasing in certain areas and strains. In general, doxycycline is the recommended first-line antibiotic for non-pregnant adults. Azithromycin is first-line for children and pregnant women and second-line for others. Other recommendations vary, but SMX/TMP is generally a second-line antibiotic for children if the strain in an outbreak is susceptible. Ciprofloxacin is second- or third-line in non-pregnant adults and, although generally avoided in children, can be used as second-line if strains are resistant to SMX/TMP.

§ This antibiotic should not be given to pregnant women.

‖ Metronidazole is not recommended but may be used in patients intolerant of vancomycin and fidaxomicin.

¶ Treatment should be followed by a course of iodoquinol for 20 days or paromomycin for 7 days.

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