Amoxicillin + Clavulanic Acid

Amoxicillin is a broad-spectrum beta-lactam antibiotic that inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins. Clavulanic acid is a beta-lactamase inhibitor that irreversibly binds to and inactivates a wide range of bacterial beta-lactamase enzymes, thereby protecting amoxicillin from hydrolysis and extending its antibacterial spectrum against many resistant strains. Combination rationale: Amoxicillin is a potent broad-spectrum penicillin, but its effectiveness can be compromised by bacterial resistance mediated by beta-lactamase enzymes. Clavulanic acid acts as a beta-lactamase inhibitor, safeguarding amoxicillin from enzymatic degradation. This combination synergistically expands the antibacterial spectrum of amoxicillin to include many beta-lactamase producing strains, enhancing its clinical utility against a wider range of bacterial infections.

Adult

Standard oral dose: 250mg amoxicillin/125mg clavulanic acid (375mg total) three times daily, or 500mg amoxicillin/125mg clavulanic acid (625mg total) two or three times daily, or 875mg amoxicillin/125mg clavulanic acid (1000mg total) twice daily, depending on severity and site of infection. Available as tablets, dispersible tablets, and suspension.

Pediatric

Dosing is based on the amoxicillin component, typically 20-45 mg/kg/day in divided doses (e.g., every 8-12 hours). For severe infections, up to 90 mg/kg/day of amoxicillin may be used. Clavulanic acid component remains at 10 mg/kg/day. Available as oral suspension (e.g., 125mg/31.25mg per 5ml, 200mg/28.5mg per 5ml, 400mg/57mg per 5ml).

Renal adjustment

Creatinine Clearance (CrCl) >30 mL/min: No adjustment. CrCl 10-30 mL/min: 250mg/125mg or 500mg/125mg every 12 hours. CrCl <10 mL/min: 250mg/125mg or 500mg/125mg every 24 hours. Hemodialysis: 250mg/125mg or 500mg/125mg every 24 hours, with an additional dose during and at the end of dialysis.

Hepatic adjustment

Use with caution; regular monitoring of hepatic function is recommended. If hepatic impairment is severe, dose reduction or discontinuation may be necessary. Contraindicated in patients with a history of amoxicillin/clavulanic acid-associated jaundice/hepatic dysfunction.

Geriatric

No specific dose adjustment is required unless there is evidence of impaired renal function. Monitor renal function in elderly patients.

Max dose

Maximum daily dose is typically 6g amoxicillin and 600mg clavulanic acid for IV administration, and for oral administration, it varies depending on formulation, but generally not exceeding 3000mg amoxicillin and 375mg clavulanic acid per day (e.g., three 875mg/125mg tablets).

• Hypersensitivity to amoxicillin, clavulanic acid, or any other penicillin
• History of severe immediate hypersensitivity reaction (e.g., anaphylaxis) to any other beta-lactam agent (e.g., cephalosporin, carbapenem)
• History of jaundice/hepatic dysfunction associated with amoxicillin/clavulanic acid
• Patients with infectious mononucleosis (due to risk of maculopapular rash)