What is the dose, age, and frequency of Amox-Clav (Amoxicillin-Clavulanate) 625MG for Lower Respiratory Tract Infections (LRTIs)?

Amoxicillin-Clavulanate 625mg Dosing for Lower Respiratory Tract Infections

For adults with LRTIs, amoxicillin-clavulanate 625mg (500mg/125mg) should be administered three times daily (every 8 hours) orally, with treatment duration of 7-14 days depending on clinical response. 1

Standard Adult Dosing

• 625mg (500mg amoxicillin/125mg clavulanate) three times daily is the recommended dose for respiratory tract infections and more severe infections 1
• The alternative dosing is 875mg/125mg twice daily (every 12 hours), which may be preferred for improved compliance 1
• Treatment duration is typically 7-14 days, with most patients showing clinical improvement within 3-4 days 2, 3

Age-Specific Considerations

Adults (≥18 years)

• Standard dose: 625mg three times daily 1
• For severe infections or COPD exacerbations: 625mg three times daily or 875mg/125mg twice daily 2
• Patients aged 60+ years: Same dosing as younger adults 4

Pediatric Patients (≥40kg body weight)

• Can be dosed according to adult recommendations once they weigh 40kg or more 1
• For children <40kg, weight-based dosing (40-45 mg/kg/day divided) should be used instead 1

Specific LRTI Indications

COPD Exacerbations

• 625mg three times daily for patients meeting Anthonisen criteria (increased dyspnea, sputum volume, and purulence) 2
• Co-amoxiclav is specifically recommended as first-line therapy for hospitalized COPD exacerbations 2
• Alternative: 875mg/125mg twice daily 2

Community-Acquired Pneumonia (Non-Severe)

• 625mg three times daily orally for non-severe pneumonia managed in hospital 2
• For severe pneumonia requiring IV therapy: 1.2g three times daily intravenously, then switch to oral 625mg three times daily when clinically stable (typically by day 3) 2

Acute Bronchitis

• 625mg three times daily when bacterial infection is suspected 2
• Note: Antibiotics provide minimal benefit in uncomplicated acute bronchitis without pneumonia 4

Renal Impairment Adjustments

Critical dosing modifications are required for renal dysfunction: 1

• GFR 10-30 mL/min: 500mg/125mg every 12 hours (not three times daily)
• GFR <10 mL/min: 500mg/125mg every 24 hours
• Hemodialysis patients: 500mg/125mg every 24 hours, plus additional dose during and after dialysis
• Do NOT use 875mg/125mg formulation if GFR <30 mL/min 1

Treatment Duration and Monitoring

• Expected clinical improvement within 3 days of starting therapy 5, 3
• If no improvement by day 3-5, reassess for treatment failure and consider alternative antibiotics 2
• Complete treatment course of 7-14 days even if symptoms improve earlier 6, 3
• For COPD exacerbations, 5-7 days is typically sufficient 5

Important Clinical Considerations

When Co-Amoxiclav is Preferred

• COPD exacerbations with purulent sputum (Type I or II Anthonisen) 2
• Coverage needed for β-lactamase producing organisms (H. influenzae, M. catarrhalis) 7
• Moderate to severe respiratory tract infections requiring hospitalization 2

When to Avoid or Use Alternatives

• Pseudomonas risk factors present (recent hospitalization, frequent antibiotics, FEV1 <30%, oral steroids >10mg/day): Use ciprofloxacin or levofloxacin instead 2, 5
• Uncomplicated acute bronchitis without pneumonia: Antibiotics provide minimal benefit and cause more harm (nausea, rash, diarrhea) 4
• Penicillin allergy: Use macrolide (clarithromycin 500mg twice daily) or fluoroquinolone (levofloxacin 500mg daily) 2

Common Pitfalls to Avoid

• Do not substitute two 250mg/125mg tablets for one 500mg/125mg tablet - they contain different amounts of clavulanate and are not equivalent 1
• Do not use 875mg/125mg formulation in moderate-severe renal impairment (GFR <30 mL/min) 1
• Do not prescribe for simple acute bronchitis without evidence of bacterial infection - this increases adverse effects without benefit 4
• Do not continue beyond 3 days without reassessment if patient shows no improvement 2, 5

Adverse Effects Profile

• Common side effects: Diarrhea (most common), nausea, rash 1, 4
• Number needed to harm: 21 for gastrointestinal effects or rash 4
• Twice daily dosing (875mg/125mg) reduces GI side effects compared to three times daily due to lower total daily clavulanate dose 8
• One case of anaphylaxis reported per 1000+ patients 4