What is the therapeutic dose of co-amoxiclav (amoxicillin/clavulanate)?

Therapeutic Dosage of Co-Amoxiclav (Amoxicillin/Clavulanate)

The therapeutic dose of co-amoxiclav for adults is typically 500 mg/125 mg every 12 hours for mild infections or 875 mg/125 mg every 12 hours for more severe infections and respiratory tract infections. 1

Adult Dosing

• For mild to moderate infections: 500 mg/125 mg every 12 hours or 250 mg/125 mg every 8 hours 1
• For severe infections and respiratory tract infections: 875 mg/125 mg every 12 hours or 500 mg/125 mg every 8 hours 1
• For moderate-severe COPD exacerbations without risk factors for Pseudomonas aeruginosa: Co-amoxiclav is recommended as a first-line treatment 2
• For intra-abdominal infections with adequate source control: Amoxicillin/Clavulanate 2 g/0.2 g every 8 hours in non-critically ill, immunocompetent patients 2

Pediatric Dosing

• For children ≥12 weeks with more severe infections: 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours 3
• For children ≥12 weeks with less severe infections: 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours 3
• For acute bacterial rhinosinusitis in children: Amoxicillin/clavulanate at 90 mg/6.4 mg/kg per day is recommended 2
• Children weighing 40 kg or more should be dosed according to adult recommendations 1

Special Considerations

Renal Impairment

• Patients with glomerular filtration rate (GFR) of 10-30 mL/min: 500 mg/125 mg or 250 mg/125 mg every 12 hours, depending on infection severity 1
• Patients with GFR <10 mL/min: 500 mg/125 mg or 250 mg/125 mg every 24 hours, depending on infection severity 1
• Hemodialysis patients: 500 mg/125 mg or 250 mg/125 mg every 24 hours, with additional doses during and at the end of dialysis 1
• Patients with severely impaired renal function (GFR <30 mL/min) should not receive the 875 mg/125 mg formulation 1

Specific Indications

• For sinusitis: 875/125 mg twice daily for 10-14 days, with treatment continuing until the patient is well for 7 days 4
• For patients with suspected resistant organisms or treatment failure: High-dose regimen of 90 mg/kg amoxicillin and 6.4 mg/kg clavulanate (not to exceed 2 g every 12 hours) 4
• For acute otitis media: High-dose amoxicillin-clavulanate is recommended in children who have received amoxicillin in the previous 30 days or with otitis-conjunctivitis 2

Administration Guidelines

• Co-amoxiclav may be taken without regard to meals; however, absorption of clavulanate potassium is enhanced when taken at the start of a meal 1
• To minimize gastrointestinal intolerance, co-amoxiclav should be taken at the start of a meal 1
• The clavulanic acid dose in adult formulations is restricted to 125 mg because of tolerability issues 5

Common Pitfalls and Caveats

• Two 250 mg/125 mg tablets are not equivalent to one 500 mg/125 mg tablet due to the same amount of clavulanic acid (125 mg) in both formulations 1
• Gastrointestinal disturbances are the most common adverse events associated with co-amoxiclav 6
• In areas with high prevalence of penicillin-resistant S. pneumoniae, higher doses may be necessary 2
• Empirical and overuse of co-amoxiclav may select for resistance in Gram-negative pathogens, particularly in the context of rising extended-spectrum beta-lactamase (ESBL) prevalence globally 5

By following these dosing recommendations based on infection severity, patient characteristics, and specific indications, clinicians can optimize the therapeutic benefits of co-amoxiclav while minimizing the risk of adverse effects and antimicrobial resistance.