What is the role of Azithromycin (AZI) in treating a 1-week duration of diarrhea suspected to be of bacterial cause?

From the Guidelines

Azithromycin should be considered as a first-line treatment for a 1-week duration of diarrhea suspected to be of bacterial cause, particularly in cases of dysentery or acute watery diarrhea with high fever, due to its efficacy against common diarrheal pathogens and low resistance rates 1. When evaluating the role of azithromycin in treating bacterial diarrhea, several factors must be considered, including the severity of illness, the likelihood of treatment efficacy, and regional patterns of antimicrobial resistance.

• The decision to treat diarrhea with azithromycin should be based on the assessment of the severity of illness and the potential impact on the patient's activities and plans.
• Azithromycin has been shown to be effective in reducing symptom duration in travelers' diarrhea, with a strong recommendation and high level of evidence supporting its use as first-line therapy for dysentery and acute watery diarrhea with high fever 1.
• The antibiotic has a broad spectrum of activity against common diarrheal pathogens, including Campylobacter, Shigella, and some strains of Salmonella and E. coli.
• Azithromycin is generally well-tolerated, with minimal side effects, although nausea and vomiting can occur, particularly when administered as a single 1-gm dose 1.
• The recommended dosage of azithromycin for treating bacterial diarrhea is 500mg once daily for 3 days or a single 1-gm dose 1.
• It is essential to consider the potential risks and benefits of antibiotic therapy, including the development of resistance, alteration of gut microbiota, and potential side effects, and to use azithromycin judiciously and only when necessary 1.

From the Research

Azithromycin in Treating 1-Week Diarrhea

• Azithromycin is a preferred first-line antibiotic for treating acute watery diarrhea, febrile diarrhea, and dysentery 2.
• The recommended dose for acute watery diarrhea is a single dose of 500 mg, while for febrile diarrhea and dysentery, a single dose of 1,000 mg is recommended 2.
• Azithromycin has been shown to be effective in reducing symptom severity and duration of illness in travelers' diarrhea, with a cure rate of 96% at 72 hours after treatment initiation 3.
• A study in Thailand found that single-dose azithromycin was associated with the shortest median time to the last unformed stool (35 hours) and the highest cure rate (96%) compared to 3-day azithromycin and levofloxacin regimens 3.

Combination Therapy with Loperamide

• The combination of loperamide and azithromycin has been shown to be more effective than azithromycin alone in treating travelers' diarrhea, with a shorter duration of diarrhea (11 hours vs 34 hours) and fewer unformed stools passed in the first 24 hours 4.
• Loperamide plus azithromycin was found to be safe and more effective than either dose of azithromycin alone in a study in Mexico 4.

Safety and Side Effects

• Diarrhea is a common side effect of azithromycin, with a reported incidence of 54.5% in one study, although the symptom was generally mild and resolved within 2 days 5.
• Approximately one-third of patients reported inconvenience in taking the azithromycin formulation due to ease, amount, and unpleasant bitter taste 5.

Considerations for Use

• The choice of antibiotic should take into account the travel destination and regional differences in the predominance of pathogens and resistance levels 2.
• Azithromycin is a reasonable first-line option for empirical management of traveler's diarrhea, particularly in areas with high rates of fluoroquinolone resistance 3.