Antimicrobials

Active against:

• Gram positive aerobes: Staphylococci- methicillin-sensitive strains (MSSA), Streptococci, Enterococcus faecalis
• Gram negative aerobes: most strains of coli, Klebsiella spp., Proteus spp.
• Anaerobes: most oral and gut anaerobes (e.g. fragilis)

Not active against:

• Methicillin-resistant Staphylococcus aureus (MRSA)
• Enterococcus faecium
• Pseudomonas aeruginosa
• Extended spectrum beta-lactamase (ESBL) producing organisms
• AmpC beta-lactamase producing organisms (Serratia spp., Morganella morganii, Providencia spp., Proteus spp. (not P. mirabilis), Citrobacter spp., Enterobacter spp., Hafnia spp., Pantoea spp., Klebsiella aerogenes)

Oral Formulation:

• Upper respiratory tract infections, such as sinusitis (typically reserved for non-resolving or relapsing infection)
• Lower respiratory tract infections
• Polymicrobial skin and soft tissue infections
• Urinary tract infections when polymicrobial coverage is required
• Intra-abdominal infections

IV Formulation:

The IV formulation of amoxicillin-clavulanic acid should be used instead of piperacillin-tazobactam for treatment of polymicrobial infections where Pseudomonas aeruginosa coverage is not needed and ceftriaxone containing regimens are not sufficient, including:

• Severe animal bite infections
• Severe polymicrobial skin and soft tissue infections
• Severe polymicrobial head and neck infections
• Select intra-abdominal infection where Enterococcus coverage is required

Note: IV amoxicillin-clavulanate is MORE expensive than ceftriaxone + metronidazole

Oral Formulation:

• Treatment of severe infections that require high systemic concentrations of antibiotics

IV Formulation:

• Infections which require coverage for Pseudomonas aeruginosa
• Community acquired pneumonia, urinary tract infection, intra-abdominal infection (ceftriaxone-containing regimens are recommend as first-line treatment options as they are efficacious and more cost-effective)
• Outpatient parenteral antimicrobial therapy (due to short stability)

• For use in Pregnancy and Breastfeeding, see Safe Use of Antibacterial Agents: Pregnancy & Breastfeeding section
• Avoid in patients who have had documented allergic reactions to penicillin or cross-reactive cephalosporins, see Penicillin allergy and the use of beta-lactam antibiotics

• Nausea, abdominal pain, vomiting, diarrhea
• Use should be avoided if infectious mononucleosis is suspected due to the risk of developing a morbilliform rash
• Hypersensitivity reactions including anaphylaxis
• Hepatic events have been reported predominantly in males and elderly patients and may be associated with prolonged treatment of amoxicillin-clavulanic acid

Oral Formulation:

• 875/125 mg PO Q12H or 500/125 mg PO Q8H

IV Formulation:

• Usual dose: 1000/200 mg IV Q8H

Renal Insufficiency

Oral Formulation:

• Dose adjustment not required

IV Formulation:

• > 30 mL/min: No change
• 10-30 mL/min: 500mg/100mg IV every 8 hours
• < 10 mL/min: 500mg/100mg IV every 12 hours
• HD: 500mg/100mg IV every 8 hours (cleared by dialysis)

• For preparation/administration of the IV formulation, see IV drug monograph

1. Amoxicillin Sodium and Potassium Clavulanate Product Monograph. Sandoz Canada Inc., Canada. Date of Revision: January 31, 2020.