What is the recommended dose of Amoxiclav (amoxicillin/clavulanic acid) 500/125 for adults?

Amoxiclav 500/125 mg Dosing for Adults

For adults with standard infections, Amoxiclav 500/125 mg should be dosed as one tablet three times daily, though the 875/125 mg formulation given twice daily is preferred for most respiratory and moderate-to-severe infections. 1

Standard Dosing Regimens

500/125 mg Formulation

• Standard dose: 500 mg amoxicillin/125 mg clavulanate three times daily 2
• This formulation provides adequate coverage for mild-to-moderate infections 2
• Should be taken at the start of meals to enhance clavulanate absorption and minimize gastrointestinal side effects 1

875/125 mg Formulation (Preferred for Most Infections)

• Recommended dose: 875 mg amoxicillin/125 mg clavulanate twice daily 1, 3
• This is the preferred formulation for respiratory tract infections and moderate-to-severe infections because it provides superior pharmacokinetics with less frequent dosing 1, 4
• Clinical trials demonstrate equivalent or superior efficacy compared to 500/125 mg three times daily, with improved compliance and potentially fewer gastrointestinal side effects 4, 5

Clinical Indication-Specific Dosing

Respiratory Tract Infections

• 875/125 mg twice daily is specifically recommended for respiratory infections including acute bacterial rhinosinusitis, community-acquired pneumonia, and acute exacerbations of chronic bronchitis 2, 1
• Duration: 5-7 days for adults with uncomplicated acute bacterial rhinosinusitis 2

Lyme Disease (Early Localized/Disseminated)

• 500 mg three times daily for 14 days when amoxicillin-clavulanate is used to cover both Lyme disease and bacterial cellulitis 2

Streptococcal Pharyngitis (Recurrent/Carrier State)

• 500 mg twice daily for 10 days in adults with multiple recurrent episodes 2

Skin and Soft Tissue Infections

• 875/125 mg twice daily is appropriate for standard skin infections 3

Important Clinical Considerations

Renal Impairment

• Patients with glomerular filtration rate <30 mL/min should NOT receive the 875 mg dose 1
• Dose adjustment required for severe renal impairment 1

Administration

• Take at the start of meals to optimize absorption and reduce gastrointestinal intolerance 1
• The 875/125 mg formulation may be taken without regard to meals, though meal administration is preferred 1

Common Pitfall

• Do not substitute two 250 mg tablets for one 500 mg tablet, as both contain 125 mg clavulanate, resulting in excessive clavulanate dosing 2
• The 500/125 mg three-times-daily regimen provides higher total daily clavulanate (375 mg) compared to 875/125 mg twice daily (250 mg), which may increase diarrhea risk 4

Pharmacokinetic Advantage of 875/125 mg

• Provides extended time above minimum inhibitory concentration for common respiratory pathogens 1, 6
• Achieves similar tissue penetration with less frequent dosing 6
• Demonstrates equivalent clinical and bacteriological efficacy to more frequent dosing regimens 4, 5