Antibiotics use in pets: Bacterial vs. viral infections

Q:I am thinking about changing veterinarians and want your advice. My cat was sneezing, and my veterinarian said she had an upper respiratory infection. However, the vet refused to give my cat an antibiotic for the infection. Isn’t that malpractice?

A:Most likely, your veterinarian concluded that your cat had a viral upper respiratory infection (URI), a common condition in cats. Since antibiotics kill only bacteria—but have no effect on viruses—an antibiotic wouldn’t have helped, and it may have made things worse. 

Antibiotics sometimes cause loss of appetite, diarrhea and vomiting, which surely would have made your kitty feel sicker. Even worse, indiscriminate use of antibiotics is a significant factor in the rise of antibiotic resistance. Unnecessary antibiotics kill the weakest bacteria, which are harmless or even beneficial, leaving the stronger, more resistant bacteria to thrive. The next time the antibiotic is used, it won’t be effective against those resistant bacteria.

Over time, bacteria evolve mechanisms to elude antibiotics. This process occurs more rapidly when antibiotics are carelessly prescribed and when they are added to animal feed to enhance growth.

I assume your cat recovered on her own, which further supports the diagnosis of a viral URI. Feline URIs are similar to a human’s cold, which is caused by any of about 200 viruses. The best treatment is supportive care and “tincture of time.”

Your veterinarian seems to have made an accurate diagnosis, prevented unnecessary and potentially dangerous medical therapy, and helped your cat get better—all good reasons to stick with this vet.

Lee Pickett, V.M.D. practices companion animal medicine in Pennsylvania. Contact her at askdrlee@insurefigo.com.