What is the maximum dose for amoxicillin (amoxicillin) suspension 400mg/5ml?

Maximum Dose for Amoxicillin Suspension 400mg/5ml

The maximum dose of amoxicillin suspension 400mg/5ml is 1.0 gram every 12 hours for adults, and for children, the maximum dose is 90 mg/kg/day divided into two doses (45 mg/kg twice daily). 1

Adult Dosing

• The maximum adult dose of amoxicillin is 1.0 gram every 12 hours (2 grams per day) 1
• For standard infections in adults, the typical dose is 500 mg twice daily 1
• For more severe infections or those caused by resistant organisms, the dose may be increased up to the maximum of 1.0 gram every 12 hours 1

Pediatric Dosing

• For children, amoxicillin dosing is weight-based with two standard regimens: 2
  • Standard dose: 45 mg/kg/day divided into two doses (22.5 mg/kg twice daily) for uncomplicated infections 2
  • High dose: 90 mg/kg/day divided into two doses (45 mg/kg twice daily) for children with risk factors for resistant organisms 2, 1
• The high-dose regimen (90 mg/kg/day) is recommended when there are concerns about penicillin-resistant Streptococcus pneumoniae 1, 3
• For a 400mg/5ml suspension, calculate the volume needed based on the child's weight and the prescribed dose 2

Clinical Considerations

• Higher doses (90 mg/kg/day) are recommended in areas with high prevalence of penicillin-resistant S. pneumoniae 1, 4
• The standard dose (45 mg/kg/day) may be inadequate for treating resistant organisms, particularly during viral coinfection 3
• For severe infections, twice-daily dosing at higher doses (75-90 mg/kg/day) may be more effective than three-times-daily dosing at lower doses 5
• When using the 400mg/5ml concentration, careful calculation is needed to ensure accurate dosing, especially in young children 2

Common Pitfalls

• Underdosing is a common pitfall when treating infections caused by resistant organisms 3, 4
• Using standard doses (45 mg/kg/day) when high doses (90 mg/kg/day) are indicated may lead to treatment failure 4
• Failure to adjust dosing based on the specific concentration of the suspension (400mg/5ml in this case) can lead to medication errors 2
• For beta-lactamase producing organisms, amoxicillin alone (even at high doses) may be insufficient, and amoxicillin-clavulanate may be needed 4, 2

Practical Application

• For a 20 kg child requiring high-dose therapy (90 mg/kg/day):
  • Daily dose = 20 kg × 90 mg/kg = 1800 mg
  • Divided into two doses = 900 mg twice daily
  • Using 400mg/5ml suspension: 900 mg ÷ 400 mg × 5 ml = 11.25 ml twice daily 2
• For adults, the maximum dose of 1.0 gram would require 12.5 ml of the 400mg/5ml suspension twice daily 1