Major Uses

Oxytetracycline is an antibiotic used primarily in dogs and cats to treat mycoplasma, rickettsia, spirochetes, and chlamydia. As most bacteria have become resistant to oxytetracycline, it is no longer commonly prescribed.

Common Precautions

Caution should be exercised in animals during their first half of pregnancy, as oxytetracycline can retard fetal skeletal development and discolor deciduous teeth. Caution should also be used when administering this drug to patients with renal insufficiency or hepatic impairment. Concurrent use with other nephrotoxic or hepatotoxic drugs should be avoided.

Some possible adverse effects experienced while taking oxytetracycline include yellow, brown, or gray discoloration of bones and teeth in young animals, delayed bone growth and healing, ruminal microflora depression and ruminoreticular stasis in ruminants, intravascular hemolysis with resultant hemoglobinuria, and cardiodepressant effects. Local reactions, yellow staining, and necrosis may occur at the injection site. Oxytetracycline may also cause nausea, vomiting, anorexia, diarrhea, colic, fever, depression, hair loss, urolith formation, overgrowth of non-susceptible bacteria or fungi, hepatotoxicity and blood dyscrasias.

Oxytetracycline should not be used in animals with a known allergy or hypersensitivity to the drug. A veterinarian should be contacted immediately if an overdose is suspected or any adverse side effects occur.


Oxytetracycline should be kept at room temperature in a tight, light resistant, childproof container. It should be stored where children and pets will not be able to reach it. Oxytetracycline should also be kept away from conditions that may cause freezing.


For treating susceptible infections in dogs, a typical dose ranges from 7-50 mg/kg every 8-24 hours for up to 2 weeks. For cats, a typical dose ranges from 10-25 mg/kg every 8-12 hours for 5-7 days. For horses, a dose can range from 5-20 mg/kg every 8-12 hours for up to 4 weeks. If a regularly scheduled dose is forgotten, it should be administered as soon as possible. If it is nearing time for the next dose, the missed dose should be skipped and the normal administration schedule should be continued. Two doses should not be administered at the same time, as an overdose can occur.

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.