From the Guidelines
For a 21-pound (approximately 9.5 kg) infant with otitis media, the recommended dose of amoxicillin is 80-90 mg/kg/day divided into two doses, as stated in the 2013 Pediatrics guideline 1. This translates to approximately 760-855 mg per day, which can be divided into two doses of approximately 380-428 mg twice daily. Standard amoxicillin suspension typically comes as 250 mg/5 mL or 400 mg/5 mL. Using the 400 mg/5 mL suspension, give about 4.75-5.35 mL twice daily for 10 days, but since this is not a standard measurement, it is more practical to use the 250 mg/5 mL or 400 mg/5 mL suspension and adjust the dose to the nearest available measurement, which would be approximately 5 mL of the 400 mg/5 mL suspension twice daily, or 4 mL of the 250 mg/5 mL suspension four times a day, however the 400 mg/5 mL is more convenient for twice daily dosing. Ensure the full course is completed even if symptoms improve within a few days. Administer with or without food, though giving with food may help reduce stomach upset. Watch for side effects including diarrhea, rash, or signs of allergic reaction. Keep the suspension refrigerated after reconstitution and shake well before each dose. High-dose amoxicillin is the first-line treatment for otitis media because it effectively targets Streptococcus pneumoniae, which has developed resistance to lower doses, as supported by the American Academy of Pediatrics and the American Academy of Family Physicians 1. If the child doesn't improve within 48-72 hours, follow up with the healthcare provider as an alternative antibiotic may be needed, such as amoxicillin-clavulanate, cefdinir, cefpodoxime, or ceftriaxone, as outlined in the 2013 Pediatrics guideline 1. Some key points to consider when choosing an antibiotic include the patient's history of antibiotic use, the presence of concurrent conjunctivitis, and the potential for cross-reactivity with penicillin allergy, as discussed in the 2013 Pediatrics guideline 1.
From the Research
Amoxicillin Dosage for a 21-Pound Infant with Otitis Media
- The American Academy of Pediatrics recommends amoxicillin as the first-line treatment for acute otitis media (AOM) in children 2.
- According to the study published in 1993, amoxicillin suspension was given in a dose of 20 mg/kg (maximum, 750 mg) twice daily for 7 to 10 days 3.
- To calculate the dosage for a 21-pound infant, we need to convert the weight from pounds to kilograms. Since 1 pound is approximately equal to 0.45 kilograms, a 21-pound infant would weigh approximately 9.5 kilograms.
- Using the recommended dosage of 20 mg/kg, the total daily dosage for a 9.5-kilogram infant would be 190 mg per dose, given twice daily.
Efficacy and Safety of Amoxicillin in Treating Otitis Media
- Studies have shown that amoxicillin is effective in treating AOM in children, with clinical success rates ranging from 90% to 93% 3, 4.
- However, other studies have reported that macrolide antibiotics, such as azithromycin, may be associated with increased clinical failures compared to amoxicillin 2.
- A systematic review and meta-analysis published in 2021 found that azithromycin had equivalent clinical efficacy to amoxicillin/clavulanate in treating otitis media in children, with fewer adverse events 5.
Comparison with Other Antibiotics
- A study published in 2001 compared the outcome of patients with recurrent AOM treated with either amoxicillin or azithromycin, and found that both treatments were effective in preventing recurrent AOM 6.
- Another study published in 2005 found that azithromycin was associated with a decreased risk of failure overall, compared to amoxicillin, but had an increased risk of failure during the first few days of treatment 4.