What is the recommended dosage and treatment duration for Amoxyclav (Amoxicillin-Clavulanate)?

Amoxicillin-Clavulanate (Amoxyclav/Augmentin) Dosing Guidelines

For adults with mild-to-moderate infections, use 500 mg/125 mg three times daily or 875 mg/125 mg twice daily; for respiratory tract infections or more severe infections, use 875 mg/125 mg twice daily or 2000 mg/125 mg twice daily when antibiotic resistance is likely. 1

Adult Dosing Regimens

Standard Dosing for Mild-to-Moderate Infections

• 500 mg/125 mg three times daily is the standard dose for mild-to-moderate infections including skin/soft tissue infections, uncomplicated urinary tract infections, and animal/human bites 2, 1
• 875 mg/125 mg twice daily is FDA-approved for more severe infections and all respiratory tract infections 1
• The 500/125 mg formulation provides adequate coverage for most community-acquired infections 2

High-Dose Regimens for Resistant Organisms

• 2000 mg/125 mg twice daily should be used when antibiotic resistance is likely, including: recent antibiotic use within 30 days, healthcare contact, prior treatment failure, high community resistance prevalence (>10% penicillin-resistant S. pneumoniae), age >65 years, or comorbidities (diabetes, chronic heart/lung/liver/kidney disease) 2, 3
• This high-dose regimen achieves adequate serum concentrations to eradicate penicillin-resistant S. pneumoniae with MICs up to 4-8 mg/L 3

Intravenous Dosing

• 1.2 g IV every 8 hours for serious infections including complicated intra-abdominal infections, severe respiratory infections, and severe skin/soft tissue infections 2

Pediatric Dosing

Neonates and Infants <12 Weeks

• 30 mg/kg/day divided every 12 hours (based on amoxicillin component) 1
• Use the 125 mg/5 mL oral suspension formulation 1

Children ≥12 Weeks

Standard Dosing:

• 45 mg/kg/day every 12 hours OR 40 mg/kg/day every 8 hours for more severe infections 3, 1
• 25 mg/kg/day every 12 hours OR 20 mg/kg/day every 8 hours for less severe infections 3, 1
• The every 12-hour regimen is preferred as it causes significantly less diarrhea 1

High-Dose Regimen:

• 90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate in two divided doses (maximum 2000 mg per dose) for severe infections or high-risk situations 3, 4
• Risk factors requiring high-dose therapy include: age <2 years, daycare attendance, recent antimicrobial use within 30 days, moderate-to-severe illness, or areas with >10% penicillin-resistant S. pneumoniae 4

Children ≥40 kg

• Dose according to adult recommendations 1
• Do not use 250 mg/125 mg tablets until child weighs at least 40 kg due to different amoxicillin:clavulanate ratios 1

Infection-Specific Duration

Respiratory Tract Infections

• Acute bacterial rhinosinusitis (adults): 5-7 days 2, 3
• Acute bacterial rhinosinusitis (children): 10-14 days 3
• Community-acquired pneumonia: 7-10 days, may extend to 14 days depending on clinical response 3, 4
• Acute otitis media: 10 days 1

Other Infections

• Uncomplicated urinary tract infections: 3-7 days 3
• Intra-abdominal infections: 4-7 days with adequate source control 2, 4
• Streptococcal pharyngitis/carriers: 10 days 2, 4
• Skin/soft tissue infections: 7-10 days 2

Renal Impairment Dosing

• GFR 10-30 mL/min: 500 mg/125 mg or 250 mg/125 mg every 12 hours 1
• GFR <10 mL/min: 500 mg/125 mg or 250 mg/125 mg every 24 hours 1
• Hemodialysis: 500 mg/125 mg or 250 mg/125 mg every 24 hours, with additional dose during and at end of dialysis 1
• Do not use 875 mg/125 mg dose if GFR <30 mL/min 1

Critical Dosing Considerations and Common Pitfalls

Formulation Substitution Errors

• Never substitute two 250 mg/125 mg tablets for one 500 mg/125 mg tablet - this results in excessive clavulanate dosing (250 mg vs 125 mg) 2, 1
• The 250 mg/125 mg tablet and 250 mg/62.5 mg chewable tablet are not interchangeable due to different clavulanate content 1

Clinical Response Monitoring

• Evaluate clinical response within 48-72 hours of initiating therapy 3, 4
• Fever should resolve within 24 hours for pneumococcal pneumonia, but may take 2-4 days for other etiologies 5
• If no improvement after 2-3 days, perform clinical and radiological reassessment 5

Resistance Considerations

• In areas with high penicillin-resistant S. pneumoniae prevalence (>10%), always use high-dose formulations 3
• Avoid underdosing in patients with risk factors for resistant organisms 3
• Complete the full course of therapy to prevent treatment failure and resistance development 2

Drug Interactions

• When combining with other nephrotoxic drugs or in patients with renal dysfunction, avoid aminoglycosides to minimize nephrotoxicity risk 2