Is 800mg of amoxicillin (amoxicillin) twice daily (BID) for 10 days an appropriate treatment regimen?

Appropriateness of Amoxicillin 800 mg BID for 10 Days

Administering 10 ml of amoxicillin 400 mg/5 mL BID (800 mg twice daily) for 10 days is appropriate only for specific indications and patient populations, but is not a standard dosing regimen for most common infections.

Dosage Analysis

The dosage in question (10 ml of 400 mg/5 mL BID) equals:

• 800 mg twice daily = 1600 mg total daily dose
• 10-day duration

FDA-Approved Dosing for Amoxicillin

According to the FDA label for amoxicillin 1:

• For adults with mild/moderate infections:

  • 500 mg every 12 hours or 250 mg every 8 hours

• For adults with severe infections:

  • 875 mg every 12 hours or 500 mg every 8 hours

• For pediatric patients:

  • Mild/moderate: 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours
  • Severe: 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours

Clinical Scenarios Where This Dosing May Be Appropriate

1. Pediatric Patients

For a child weighing approximately 20 kg with a severe infection:

• 40 mg/kg/day = 800 mg/day
• Given as 400 mg twice daily would be appropriate 1

2. Group A Streptococcal Pharyngitis

For treatment of strep throat in children, the IDSA guidelines recommend:

• Amoxicillin 50 mg/kg once daily (maximum = 1,000 mg) OR
• 25 mg/kg twice daily (maximum = 500 mg) for 10 days 2

For a 32 kg child, 800 mg twice daily would exceed the recommended maximum dose.

3. H. pylori Infection

For adults with H. pylori infection, the FDA label recommends:

• Triple therapy: 1 gram amoxicillin twice daily for 14 days
• Dual therapy: 1 gram amoxicillin three times daily for 14 days 1

The 800 mg BID dosing would be suboptimal for H. pylori eradication.

Inappropriate Scenarios

This dosing would be inappropriate in:

1. Adult patients with mild/moderate infections: The dose exceeds standard recommendations of 500 mg BID 1

2. Small children: For a child weighing less than 20 kg, this dose would exceed the 40 mg/kg/day recommendation for severe infections 1

3. H. pylori treatment: The dose is insufficient compared to the recommended 1 gram twice daily 1, 2

4. Patients with severe renal impairment: Patients with GFR <30 mL/min require dose adjustment 1

Potential Risks of Inappropriate Dosing

1. Overdosing: May lead to increased adverse effects including diarrhea, nausea, and vomiting

2. Underdosing: May lead to treatment failure and potential development of antibiotic resistance

3. Duration concerns: While 10 days is appropriate for streptococcal infections 2, shorter durations may be sufficient for other indications, such as community-acquired pneumonia in children (5 days) 3

Conclusion

The dosage of amoxicillin 800 mg (10 ml of 400 mg/5 mL) twice daily for 10 days may be appropriate in specific clinical scenarios, primarily for larger pediatric patients with severe infections. However, it is not a standard dosing regimen for most adult infections and could represent either overdosing or underdosing depending on the specific indication and patient characteristics.

For most common indications in adults, standard dosing of 500 mg three times daily or 875 mg twice daily would be more appropriate 1. For children, weight-based dosing should be calculated to ensure proper treatment.