Adult Dosing of Amoxicillin for a 12-Year-Old with Ear Infection
No, your 12-year-old daughter who weighs 85 pounds (approximately 38.6 kg) should not take an adult dose of medication for an ear infection. Instead, she should receive a weight-appropriate pediatric dose of amoxicillin.
Appropriate Dosing for Ear Infections in Children
Weight-Based Dosing for Amoxicillin
- For children weighing less than 40 kg (88 lb), amoxicillin should be dosed at 45 mg/kg/day divided into two doses every 12 hours or 40 mg/kg/day divided into three doses every 8 hours for ear infections 1
- For your daughter weighing 85 pounds (38.6 kg), this would calculate to approximately 1,737 mg per day divided into two doses (869 mg twice daily) or 1,544 mg per day divided into three doses (515 mg three times daily)
- This is significantly different from the adult dose of 500 mg three times daily or 875 mg twice daily 1
Importance of Pediatric Dosing
- Children are not simply "small adults" and require individualized dosing based on their weight, age, and organ maturity 2
- Inappropriate dosing can lead to treatment failure or increased risk of adverse effects 2
- For ear infections specifically, studies show that higher doses of amoxicillin (80-90 mg/kg/day) are often recommended to effectively treat resistant Streptococcus pneumoniae 3, 4
Clinical Considerations for Ear Infections
Treatment Recommendations
- Amoxicillin remains the first-line treatment for acute otitis media (ear infection) in children who are not allergic to penicillin 4
- For children with ear infections, treatment should be continued for a minimum of 48-72 hours beyond symptom resolution 1
- If symptoms persist despite 48-72 hours of amoxicillin therapy, the child should be reexamined and potentially switched to a second-line agent such as amoxicillin/clavulanate 4
Common Pathogens
- The most common bacterial causes of ear infections are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis 4
- Viral co-infection can reduce the effectiveness of antibiotics and may require higher dosing 3
Safety Considerations
Risks of Inappropriate Dosing
- Using adult doses in children can lead to overdosing, which may increase the risk of side effects 2
- Underdosing (using a dose that's too low) may lead to treatment failure and potentially contribute to antibiotic resistance 3
Proper Administration
- To minimize gastrointestinal intolerance, amoxicillin should be taken at the start of a meal 1
- For oral suspension forms, proper reconstitution and shaking before use is essential 1
Bottom Line
For your 12-year-old daughter weighing 85 pounds, the appropriate dose of amoxicillin for an ear infection would be weight-based, not an adult dose. Consult with your healthcare provider for the exact prescription and dosing instructions based on the severity of the infection and local resistance patterns.