What are the most effective antibiotics for treating traveler's diarrhea (Gastroenteritis acquired during travel)?

From the Guidelines

Azithromycin should be considered the first-line agent for traveler's diarrhea, particularly in cases of dysentery or acute watery diarrhea with greater than mild fever, due to its efficacy and the increasing resistance of fluoroquinolones. The choice of antibiotic for traveler's diarrhea depends on the severity of the illness, the geographic region, and the likelihood of antibiotic resistance. According to the guidelines for the prevention and treatment of travelers' diarrhea, azithromycin (1000mg single dose or 500mg daily for 3 days) is recommended as the first-line treatment for moderate to severe traveler's diarrhea, especially in areas with high rates of fluoroquinolone resistance, such as Southeast Asia 1.

Some key points to consider when choosing an antibiotic for traveler's diarrhea include:

• The efficacy of the antibiotic against common bacterial causes of traveler's diarrhea, such as E. coli, Salmonella, Shigella, and Campylobacter
• The likelihood of antibiotic resistance in the geographic region
• The safety and tolerability of the antibiotic
• The simplicity of the treatment regimen and patient adherence

In addition to azithromycin, other antibiotics that may be considered for traveler's diarrhea include fluoroquinolones, such as ciprofloxacin (500mg twice daily for 1-3 days), and rifaximin (200mg three times daily for 3 days), which is a non-absorbable antibiotic that works well for non-invasive diarrhea. However, the use of fluoroquinolones is limited by the increasing resistance of common bacterial causes of traveler's diarrhea, particularly in Southeast Asia 1.

It's also important to note that antibiotics should be reserved for moderate to severe cases of traveler's diarrhea, and that mild cases often resolve on their own within a few days. Travelers should pack these medications before their trip after consulting with their healthcare provider about the best option for their specific destination and medical history. Staying hydrated and considering adding loperamide (Imodium) for symptom relief are also important aspects of managing traveler's diarrhea 1.

From the FDA Drug Label

XIFAXAN is indicated for the treatment of travelers’ diarrhea (TD) caused by noninvasive strains of Escherichia coli in adults and pediatric patients 12 years of age and older XIFAXAN was not found to be effective in patients with diarrhea complicated by fever and/or blood in the stool or diarrhea due to pathogens other than Escherichia coli. The best antibiotic for traveler’s diarrhea is rifaximin (XIFAXAN), but only for cases caused by noninvasive strains of Escherichia coli in adults and pediatric patients 12 years of age and older 2.

• It is not effective for diarrhea complicated by fever and/or blood in the stool or diarrhea due to pathogens other than Escherichia coli.
• Alternative antibiotic therapy should be considered if diarrhea symptoms get worse or persist more than 24 to 48 hours 2.
• Rifaximin (XIFAXAN) should not be used in patients where Campylobacter jejuni, Shigella spp., or Salmonella spp. may be suspected as causative pathogens 2.

From the Research

Best Antibiotics for Traveler's Diarrhea

• The most effective antibiotics for traveler's diarrhea include azithromycin, fluoroquinolones, and rifaximin 3, 4, 5, 6.
• Azithromycin is the drug of choice, especially in Asia where Campylobacter is common 3.
• Fluoroquinolone antibiotics are effective in Latin America and Africa where ETEC is predominant 3.
• Rifaximin is a suitable option for prevention and treatment of traveler's diarrhea, especially for patients with chronic comorbidities 3, 7, 5.

Treatment Guidelines

• For mild traveler's diarrhea, the use of antibiotics is not recommended, and bismuth subsalicylate or loperamide may be considered 6.
• For moderate traveler's diarrhea, antibiotics such as fluoroquinolones, azithromycin, and rifaximin may be used, and loperamide may be considered as monotherapy or adjunctive therapy 6.
• For severe traveler's diarrhea, antibiotics such as azithromycin, fluoroquinolones, and rifaximin should be used 6.

Considerations for Patients with Chronic Comorbidities

• Patients with chronic comorbidities, such as diabetes, hypertension, or cardiovascular disease, should be cautious when taking antibiotics for traveler's diarrhea due to potential drug interactions 7.
• Levofloxacin and rifaximin are considered safe for patients with hypertension, and rifaximin exhibits mild interaction only with metformin 7.