What is the typical dosing of amoxiclav (amoxicillin-clavulanate) for bacterial infections?

Amoxicillin-Clavulanate Dosing for Bacterial Infections

For most adult bacterial infections, prescribe amoxicillin-clavulanate 875/125 mg twice daily, taken at the start of meals to minimize gastrointestinal side effects. 1, 2, 3

Standard Adult Dosing Regimens

First-Line Dosing

• 875/125 mg twice daily is the standard dose for most bacterial infections in adults, including respiratory tract infections, sinusitis, skin and soft tissue infections, and bite wounds 1, 2, 3
• An alternative regimen of 500/125 mg three times daily may be used, particularly for respiratory tract infections 2
• Take at the start of meals to enhance clavulanate absorption and reduce gastrointestinal intolerance 3

High-Dose Therapy for Resistant Pathogens

Use 2000/125 mg twice daily when antibiotic resistance is likely, including: 4

• Recent antibiotic use within the past 30 days
• Recent healthcare contact or hospitalization
• High community prevalence of resistant Streptococcus pneumoniae (>10%)
• Age >65 years or immunocompromised status
• Moderate to severe infections (frontal/sphenoidal sinusitis)
• Comorbidities (diabetes, chronic heart/lung/liver/kidney disease)

This high-dose formulation achieves adequate serum concentrations to eradicate penicillin-resistant S. pneumoniae with MICs up to 4-8 mg/L 4

Pediatric Dosing

Standard Pediatric Dosing (≥12 weeks)

• Less severe infections: 25 mg/kg/day every 12 hours or 20 mg/kg/day every 8 hours 4
• More severe infections: 45 mg/kg/day every 12 hours or 40 mg/kg/day every 8 hours 4, 2
• Calculate dose based on actual body weight, not age, to avoid underdosing 2

High-Dose Pediatric Therapy

Use 90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate in two divided doses for: 4

• Acute bacterial rhinosinusitis
• Acute otitis media with recent antibiotic use (within 30 days)
• Otitis-conjunctivitis syndrome
• Age <2 years with risk factors
• Daycare attendance
• Areas with high penicillin-resistant S. pneumoniae prevalence

Infection-Specific Dosing and Duration

Respiratory Tract Infections

• Acute bacterial rhinosinusitis (adults): 875/125 mg twice daily for 5-7 days 1, 4, 2
• Acute bacterial rhinosinusitis (children): 90 mg/kg/day for 10-14 days 4
• Community-acquired pneumonia (moderate severity): 875/125 mg twice daily or 500/125 mg three times daily for 7-10 days 4, 2
• COPD exacerbations: Co-amoxiclav as first-line treatment for moderate-severe exacerbations without Pseudomonas risk 4

Skin and Soft Tissue Infections

• Animal or human bites: 875/125 mg twice daily for 5-7 days 1
• General skin/soft tissue infections: Treat for 5-7 days after clinical improvement 1

Intra-Abdominal Infections

• Non-critically ill patients with adequate source control: 2 g/0.2 g IV every 8 hours 1, 4

Urinary Tract Infections

• Uncomplicated UTI: 3-7 days of therapy 4

Intravenous Dosing

Hospital-Based IV Therapy

• Moderate to severe infections: 1.2 g IV every 8 hours (three times daily) 1
• Critically ill patients or severe sepsis: Consider every 6 hours (QID) dosing for optimal bacterial killing 1
• Mild to moderate uncomplicated infections: BID dosing may be acceptable in outpatient settings 1

Special Populations

Renal Impairment

• Patients with GFR <30 mL/min should not receive the 875 mg dose 3
• Dose reduction generally not required unless renal impairment is severe 3

Administration Pearls

Optimizing Tolerability

• Administer at the start of meals to minimize gastrointestinal side effects 2, 3
• Twice-daily dosing (875/125 mg) is associated with less moderate-to-severe diarrhea compared to three-times-daily dosing (500/125 mg) 5
• Oral suspension must be shaken well before each use and refrigerated 2
• Reconstituted suspension expires after 14 days 2

Clinical Monitoring

• Evaluate clinical response within 48-72 hours of initiating therapy 4
• If no improvement, consider alternative management or high-dose therapy 4

Critical Pitfalls to Avoid

• Never underdose in children: Always calculate based on actual body weight, not age 2
• Avoid standard dosing in high-resistance areas: Use high-dose formulations when penicillin-resistant S. pneumoniae prevalence exceeds 10% 4
• Do not use 875 mg dose in severe renal impairment (GFR <30 mL/min) 3
• Avoid co-administration with probenecid, and monitor prothrombin time with oral anticoagulants 1