Can Azithromycin (Azee) Cause Diarrhea in Children?
Yes, azithromycin commonly causes diarrhea in children, with gastrointestinal side effects being the most frequently reported adverse events, occurring in approximately 9% of pediatric patients on average. 1
Incidence of Diarrhea by Dosing Regimen
The frequency of diarrhea varies significantly based on the dosing schedule used:
- Single-day regimen (30 mg/kg): Diarrhea occurs in 4.3% of children 2
- 3-day regimen (10 mg/kg/day): Diarrhea occurs in 2.6% of children 2
- 5-day regimen (standard dosing): Diarrhea occurs in 1.8% to 5.8% of children, depending on the specific indication 2
For community-acquired pneumonia using the 10 mg/kg on Day 1 followed by 5 mg/kg on Days 2-5 regimen, diarrhea/loose stools occurred in 5.8% of children 2. For pharyngitis/tonsillitis using 12 mg/kg for 5 days, diarrhea occurred in 5.4% of children 2.
Severity and Clinical Significance
- The gastrointestinal side effects, including diarrhea, are typically mild to moderate in severity and reversible upon discontinuation 2, 1
- Only approximately 1% of pediatric patients discontinue treatment due to adverse effects, with most discontinuations related to gastrointestinal symptoms including diarrhea 2
- The side effects very seldom necessitate withdrawal of treatment 1
Comparative Safety Profile
When compared to other antibiotics commonly used in children:
- Azithromycin versus amoxicillin/clavulanate: In acute bacterial sinusitis, azithromycin caused diarrhea in 17% of patients compared to 32% with amoxicillin/clavulanate, demonstrating a significantly lower incidence 2
- Azithromycin versus clarithromycin: For community-acquired pneumonia, gastrointestinal adverse events were comparable between azithromycin (25%) and clarithromycin (29%), with diarrhea rates of 5-9% in both groups 2
Important Clinical Considerations
- Higher doses increase risk: Single-dose 30 mg/kg and 3-day 20 mg/kg/day regimens are associated with more adverse effects compared to conventional dosing 1
- Other gastrointestinal symptoms: Beyond diarrhea, children may experience abdominal pain (1.2-3.4%), vomiting (1.1-5.6%), and nausea (0.4-1.9%), depending on the dosing regimen 2
- Palatability advantage: Despite the gastrointestinal side effects, children generally find the oral suspension agreeable in color and taste, which aids compliance 1
Serious but Rare Gastrointestinal Complications
While diarrhea is common and typically benign, azithromycin can rarely cause more serious gastrointestinal complications:
- Pseudomembranous colitis (Clostridioides difficile infection) has been reported 3
- Cholestatic jaundice occurs rarely 3, 2
These serious complications are exceedingly uncommon but should be considered if diarrhea is severe, persistent, or accompanied by fever or blood in stool.
Clinical Bottom Line
Diarrhea is an expected and common side effect of azithromycin in children, but it is usually mild, self-limited, and does not require treatment discontinuation. Parents should be counseled about this possibility when azithromycin is prescribed, but reassured that the benefit-risk profile remains favorable for appropriate indications 1.