What is the recommended dose of amoxicillin (antibiotic)?

From the Guidelines

The recommended dose of amoxicillin is 875/125 mg twice daily for adults and 25 mg/kg/d of the amoxicillin component in 2 divided doses for children, as stated in the most recent guidelines from the Infectious Diseases Society of America 1.

Key Considerations

• The dose of amoxicillin may vary based on the type and severity of the infection, as well as the patient's age and weight.
• For mild to moderate infections, the typical dose is 250-500 mg every 8 hours or 500-875 mg every 12 hours for adults.
• Children's dosing is weight-based, usually 20-90 mg/kg/day divided into 2-3 doses.
• Treatment duration typically ranges from 7-14 days depending on the infection, with most common infections requiring 7-10 days of therapy.

Important Notes

• Amoxicillin works by inhibiting bacterial cell wall synthesis, making it effective against many gram-positive and some gram-negative bacteria.
• Common side effects include diarrhea, rash, and nausea.
• Patients with penicillin allergy should not take amoxicillin, and dosage adjustments are necessary for those with severe kidney impairment.
• It is essential to complete the full course of treatment even if symptoms improve, and to take amoxicillin with or without food, though taking with food may reduce stomach upset.

Evidence-Based Recommendations

• The guidelines from the Infectious Diseases Society of America 1 provide the most recent and highest quality evidence for the recommended dose of amoxicillin.
• The guidelines recommend amoxicillin-clavulanate 875/125 mg twice daily for adults and 25 mg/kg/d of the amoxicillin component in 2 divided doses for children.
• Other studies, such as those from 2005 1 and 2014 1, provide additional evidence for the use of amoxicillin in various infections, but the most recent guidelines from the Infectious Diseases Society of America 1 should be prioritized.

From the FDA Drug Label

To minimize the potential for gastrointestinal intolerance, amoxicillin should be taken at the start of a meal. Table 1 (12 weeks) n 40 kg Recommended Dosage for Pediatric Patients Aged 3 Months and Older and Weight Less than 40 kg Ear/Nose/Throat Skin/Skin Structure Genitourinary Tract Mild/ Moderate 500 mg every 12 hours or 250 mg every 8 hours 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours Severe 875 mg every 12 hours or 500 mg every 8 hours 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours Lower Respiratory Tract Mild/ Moderate or Severe 875 mg every 12 hours or 500 mg every 8 hours 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours Due to incompletely developed renal function affecting elimination of amoxicillin in this age group, the recommended upper dose of amoxicillin is 30 mg/kg/day divided every 12 hours. Triple therapy:The recommended adult oral dose is 1 gram amoxicillin, 500 mg clarithromycin, and 30 mg lansoprazole, all given twice daily (every 12 hours) for 14 days. Dual therapy:The recommended adult oral dose is 1 gram amoxicillin and 30 mg lansoprazole, each given three times daily (every 8 hours) for 14 days.

The recommended dose of amoxicillin is:

• For adults and pediatric patients aged 3 months and older and weight greater than 40 kg:
  • Mild/Moderate infections: 500 mg every 12 hours or 250 mg every 8 hours
  • Severe infections: 875 mg every 12 hours or 500 mg every 8 hours
• For pediatric patients aged 3 months and older and weight less than 40 kg:
  • Mild/Moderate infections: 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours
  • Severe infections: 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours
• For pediatric patients aged less than 12 weeks (3 months): 30 mg/kg/day divided every 12 hours
• For H. pylori infection in adults:
  • Triple therapy: 1 gram amoxicillin, 500 mg clarithromycin, and 30 mg lansoprazole, all given twice daily (every 12 hours) for 14 days
  • Dual therapy: 1 gram amoxicillin and 30 mg lansoprazole, each given three times daily (every 8 hours) for 14 days 2

From the Research

Recommended Dose of Amoxicillin

The recommended dose of amoxicillin can vary depending on the patient's condition and the severity of the infection.

• For patients with normal kidney function, a standard dose of 1000 mg every 6 hours is commonly used 3.
• However, for patients with impaired kidney function, the recommended dose may need to be adjusted to avoid subtherapeutic drug exposure 3.
• A study found that amoxicillin clearance can be well predicted with body weight and CKD-EPI, which can help guide dose adjustments in patients with impaired kidney function 3.
• Another study found that a linear relationship between the beta of amoxicillin and creatinine clearance can be used to adjust the dosage regimen for patients with renal impairment 4.

Dosing Frequency

The frequency of amoxicillin dosing can also vary depending on the specific condition being treated.

• A study found that dosing amoxicillin/clavulanate every 12 hours is as effective as dosing every 8 hours for the treatment of lower respiratory tract infection 5.
• Another study found that amoxicillin and clavulanate given every 12 hours is as effective and safe as administration every 8 hours for the treatment of acute bacterial maxillary sinusitis 6.
• The specific dose and dosing frequency of amoxicillin may vary depending on the condition being treated, such as acute ear, nose, and throat infections 7.