What is the recommended dose of Augmentin (amoxicillin/clavulanate) for an adult patient with a bacterial infection?

Augmentin Dosing for Adults

For most adult bacterial infections, use Augmentin 875 mg/125 mg twice daily, which is the preferred regimen for respiratory tract infections including sinusitis, pneumonia, and bronchitis. 1, 2

Standard Dosing Regimens

Respiratory Tract Infections (Preferred Indication)

• 875 mg/125 mg twice daily is the first-line dose for acute bacterial rhinosinusitis, community-acquired pneumonia, and acute exacerbations of chronic bronchitis 1, 3, 2
• Duration: 5-7 days for uncomplicated acute bacterial rhinosinusitis 1, 3
• Duration: 7-10 days for most other respiratory infections 3
• This twice-daily regimen achieves clinical success rates of 91.5-93% and causes significantly less diarrhea (1% vs 2%) compared to three-times-daily dosing 3

Alternative Standard Dosing

• 500 mg/125 mg three times daily is acceptable for mild-to-moderate infections when twice-daily dosing is not preferred 1, 2
• This provides adequate coverage but requires more frequent administration 2

High-Dose Regimen for Resistant Pathogens

• 2000 mg/125 mg (2 g/125 mg) twice daily for high-risk respiratory infections or drug-resistant Streptococcus pneumoniae 4, 1
• Use this dose in areas with 25-50% penicillin-resistant S. pneumoniae prevalence 2
• This pharmacokinetically enhanced formulation (Augmentin XR) overcomes resistance through increased drug exposure 5

Specific Clinical Indications

Skin and Soft Tissue Infections

• 500 mg/125 mg twice daily for animal or human bites 3
• 875 mg/125 mg twice daily for standard skin and soft tissue infections 3
• Duration: 7-10 days depending on severity 3

Urinary Tract Infections

• 375 mg three times daily for 6-12 days for mild-to-moderate urogenital infections 6
• Clinical success rate of approximately 70% for amoxicillin-resistant organisms 7

Streptococcal Infections (Special Scenario)

• 500 mg twice daily for 10 days for chronic streptococcal carriers with recurrent symptomatic episodes 3
• Complete the full 10-day course to prevent acute rheumatic fever, regardless of clinical improvement 3
• Note: Plain amoxicillin or penicillin V is preferred for standard acute strep pharyngitis; Augmentin is reserved for carrier states 3

Critical Dosing Pitfalls to Avoid

Never Substitute Tablet Strengths

• Do NOT substitute two 250 mg tablets for one 500 mg tablet - this results in excessive clavulanate dosing (250 mg vs 125 mg) and significantly increases gastrointestinal side effects 1, 2
• The clavulanate component is fixed at 125 mg per dose in standard adult formulations, regardless of amoxicillin content 1, 2

Treatment Failure Protocol

• If no improvement occurs after 72 hours, switch to a respiratory fluoroquinolone or escalate to high-dose amoxicillin/clavulanate (2 g/125 mg twice daily) if not already used 1, 2

Administration Timing

• Take at the start of meals to enhance absorption and minimize gastrointestinal side effects 1

Dosing Algorithm

1. Identify infection type:

   • Respiratory tract infection → 875 mg/125 mg twice daily 1, 2
   • Skin/soft tissue or bite → 500-875 mg/125 mg twice daily 3
   • Urinary tract → 375 mg three times daily 6

2. Assess resistance risk factors:

   • Age <2 or >65 years, daycare attendance, recent antibiotic use, high local resistance rates → Consider 2 g/125 mg twice daily 1, 5

3. Determine duration:

   • Uncomplicated sinusitis: 5-7 days 1, 3
   • Most other infections: 7-10 days 3
   • Streptococcal infections: Minimum 10 days 3

4. Reassess at 72 hours:

   • No improvement → Switch to fluoroquinolone or escalate dose 1, 2

The 875 mg twice-daily formulation balances efficacy, convenience, and tolerability, making it the optimal choice for most adult bacterial infections requiring Augmentin. 1, 2, 5