Amoxicillin and ampicillin
Certain Gram-positives and Gram-negatives and anaerobes but not those that produce
beta-lactamases e.g. Staphylococcus aureus and Escherichia coli. Certain Gram-negatives
are often resistant e.g. Klebsiella spp. and Pseudomonas spp.5
Gram-positive and Gram-negative aerobes and many facultative and obligate anaerobes.
Effective against those that produce beta-lactamases but certain Gram-negatives are often
resistant e.g. Klebsiella spp. and Pseudomonas spp.5
Do not cross the blood-brain barrier (BBB) or enter the eye or the prostate.
Will reach joints, bile and milk.
Will cross the placenta.
Volume of distribution
Metabolism & elimination
45-90 minutes in dogs and cats.25
74-92% absorbed in monogastrics.25
8.5 µg/ml for amoxicillin, 0.9 µg/ml for clavulanic acid.6
6.6 µg/ml for amoxicillin, 3.7 µg/ml for clavulanic acid.6
Clavulanic acid 0.32L/kg.25
Hepatic metabolism and renal clearance.25
1.5 hours for amoxicillin, 0.76 hours for clavulanic acid.26
1.2 hours for amoxicillin, 0.6 hours for clavulanic acid.27
Absorption is fast6
1.4 hours for amoxicillin, 0.9 hours for clavulanic acid.6
1.8 hours for amoxicillin, 0.75 hours for clavulanic acid.6
Data not sourced
45-80 minutes in dogs and cats.25
Poor oral absorption: 30-55% absorbed in monogastrics, decreased with food.25
Data not sourced
Parameters for oral administration in dogs unless otherwise stated.
Side effects and contra-indications may vary between presentations. Some of those seen more frequently are included here but veterinary surgeons should always refer to the Summary of Product Characteristics (SPC) for full details before prescribing a product.
Adverse reactions include nausea, vomiting, diarrhoea and skin rashes. Anaphylaxis may occur in cases of hypersensitivity.5,6
Avoid in cases of known hypersensitivity to beta-lactams.5,6
Disclaimer: Indications and doses may vary between products. The antimicrobials listed may constitute an off licence use of the product and as such should only be used according to the ‘Cascade’, further details of which are available on the RCVS, VMD and NOAH websites. Veterinary surgeons are advised to carefully check the Summary of Product Characteristics (SPC) before prescribing a product and obtain informed owner consent where required.