Major Uses

Cefazolin is a cephalosporin antibiotic used to treat various infections in dogs, cats, and horses. The drug has a broad range of activity and works by inhibiting growth of the bacteria cell wall, resulting in bacteria death. Cefazolin is sometimes prescribed to treat skin and wound infections, bone infections, pneumonia, bladder infections, and sepsis. Cefazolin is also used during surgical procedures to help prevent disease.

Common Precautions

Side effects with the use of cefazolin are usually rare and mild. When the drug is administered intramuscularly, there may be pain at the injection location, and when given intravenously, swelling of the vein caused by blood clots may also be possible. Rare bleeding disorders and seizures have been reported but very rarely. Cefazolin should be used with caution in patients with renal failure, and in females that are pregnant or lactating. Because possible drug interactions can occur, the prescribing veterinarian needs to be informed of all other medications the pet is taking prior to administration of cefazolin. For example, nephrotoxic drugs and probenecid may interact with the drug.

Cefazolin should not be administered to animals with a known allergy or hypersensitivity to the drug, other cephalosporins, or penicillins. Allergic or hypersensitive reactions may include rashes, fever, or anaphylaxis. Emergency veterinary care should be sought immediately if any of these or other unusual reactions occur.


Cefazolin should be stored in light resistant containers. If the solution is kept at room temperature, it is stable for 24 hours, and 96 hours if refrigerated. If the solution is frozen, it is stable for approximately 12 weeks.


Cefazolin is only available in injectable form, and is typically administered in hospital settings. The typical dose for dogs and cats to fight infections is 10 - 17 mg/lb (20 - 35 mg/kg) every eight hours intravenously or intramuscularly. When used for surgical prophylaxis, the typical dose for dogs and cats is 10 mg/lb (22 mg/kg) every two hours intravenously during surgery. For horses, cefazolin is used primarily to fight infections and the typical dose is 12 mg/lb (25 mg/kg) every 6-8 hours intravenously or intramuscularly. Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.

This information is for general reference only and should not be used for the diagnosis or treatment of any condition of your pet. It's intended as a general reference, this information may not include all possible uses, precautions, directions, reactions (including allergic), drug interactions, or withdrawal times. Always consult your local veterinarian and have your pet examined for any advice concerning the diagnosis and treatment of your pet, including which products and doses are most appropriate. Any trademarks are the property of their respective owners. VetDepot is not a pharmacy. All prescription products are dispensed by our Pharmacy Partner. Article last updated 2/2014.