What is Azithromycin for Cats Used to Treat?

I have to open wide to take Zithromax.
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You might have taken azithromycin for a bacterial infection. It's a common medication used for people and pets. While it's not actually approved for use in cats and dogs by the U.S. Food and Drug Administration, veterinarians are permitted to use it "off-label" for their feline and canine patients.


Marketed under the brand name Zithromax, azithromycin is an antibiotic that attacks bacteria by disabling its ability to reproduce. Once given to Kitty, it's absorbed rapidly by his body. The bacteria it does in includes several varieties of streptococci, Staphylococcus aureus, Borrelia burgdorferi, and certain Hemophilus, Mycoplasma, and Bacteroides species. While you might not be familiar with all of those, you've probably heard of chlamydia. Azithromycin is effective against some species of that bacteria.


Although your vet might prescribe azithromycin for a number of bacterial infections, in cats it's most common use is treating urinary and respiratory tract infections. If Kitty has a particularly severe ear infection he might receive azithromycin. A paste version is available for treating feline gum diseases. Various bacterial skin infections also respond to azithromycin. The intestinal parasite Cryptosporidium, which causes diarrhea and dehydration, can be eliminated via azithromycin. The drug also treats Bartonella, often called cat scratch fever. It will get rid of the Bartonella bacteria in the cat as well as in you, if Kitty gave you a good scratch.

Dosage and Administration

You might not have a hard time getting Kitty to take this medication. Azithromycin is available as a liquid, tablet, paste or chew treat. Medication used as a treat? It gets better -- available flavors include anchovy, liver, beef, cheese, bacon, chicken, duck and fish. If your cat's sort of weird, he might like marshmallow, grape, banana or tutti-fruitti. How much of the drug your vet prescribes depends on Kitty's weight, as well as the reason he's given the medication. As with all antibiotics, give Kitty the correct dosage for the exact number of days on the prescription. Even if Kitty seems better, he needs the full amount of the medication to ensure the bacteria is gone.

Side Effects

Most cats tolerate azithromycin very well. At high doses -- maybe because Kitty got into the chew treats -- the drug can cause vomiting or diarrhea. It shouldn't be given to cats suffering from liver ailments. If Kitty takes antiacids for gastrointestinal problems, speak to your vet as these may interfere with azithromycin absorption.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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