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Is my kitty supposed to get "worse" before getting better on the anitbiotic for upper respiratory?
scardenas770 posted:
My new adopted kitty has an upper respiratory illness and they prescribed him an antibiotic, but as of one day later, he seems way worse. His nose has mucus "bubbles" coming out, and he didn't before. Also his eyes have way more drainage/discharge than before and he sounds worse in the breathing. If this is normal then I won't panic and take him back in, but if he should be improved ...
srstephanie responded:
Hi scardenas770,

I'm not a vet and am just a simple cat owner, but with an interest in learning. A week ago I attended a vet CE seminar taught by Dr Richard Ford of NC State who is an expert in infectious diseases, particularly respiratory, as well as being known as the "guru of vaccines/vaccinations". I hope I learned a bit from him.

About 80% of all upper respiratory infections (URI) in cats are caused by one of two (rarely both) viruses:
1) Feline Herpesvirus-1 (FHV-1), or
2) Feline Calicivirus (FCV)

These are viruses and antibiotics will not treat them because antibiotics only treat bacterial infections. However, it is common for cats to have a secondary bacterial infection as well, which is why most vets will try antibiotics as a treatment. They will help any secondary bacterial infection but not treat the viruses.

With FCV there really isn't any specific treatment other than supportive care. The only antivirals that will work on Calici, unfortunately also work on the cat, i.e. they will kill the cat, too.

More can be done to treat FHV-1. One of the first things many try is giving an amino acid supplement called L-lysine. It can be found as both a paste (made for cats) or a powder that can be sprinkled on food. You can ask your vet about it. Lysine will not cure FHV-1. It helps because FHV-1 needs another amino acid (L-arginine) to reproduce. Giving Lysine gets in the way of the Arginine and helps slow the replication of FHV-1 ... giving the cat's immune system a better chance of getting it under control. But Lysine only helps with FHV-1 (not FCV) and is better at preventing recurrences than in treating an active infection.

For severe/difficult cases of FHV-1, there is an antiviral medication that works well in cats called Famciclovir. You may want to ask your vet about it, if your vet feels that FHV-1 may be the cause of your kitten's URI.

How old is your kitten? Has he received any vaccinations yet? There are vaccines for both FCV and FHV-1 (they always come as combo vaccines for both), some are injected vaccines and others are given in/on the nose (intranasal). Only Modified Live (not Killed Virus) vaccines should be used. But pet owners need to know that NO vaccine for FHV-1 or FCV will PREVENT infection. The reason for the vaccinations is to lessen the symptoms once infected. Full blown FHV-1 or FCV can be fatal, especially in a kitten, so the vaccinations are really important.

The other thing to keep in mind is that once infected, particularly with FHV-1 ... it is FOR LIFE. There is no cure for FHV-1 and the virus is known to "hide" (in nerve tissue in the brain) and can be dormant for years, or even life. But periods of stress can cause a recurrence. Using Lysine (and some keep their cats on it for life) can help keep the recurrences to a minimum ... and some cats never have noticeable symptoms again.

One of the "treatments" that Dr Ford has found to work well in many cats ... particularly those with severe congestion that responds to antibiotics, but only while ON the antibiotics (and FCV is usually behind it) ... is to TREAT it with the Intranasal vaccine for FHV-1/FCV. He said the results can be dramatic. He has discussed it with one of the researchers at Cornell and they think that the IN vaccine stimulates a general (innate) immunity in the nose that gets the Calicivirus under control. Again, it might be something to discuss with your vet.

For supportive care, you can try turning on a hot shower and putting your kitten in the bathroom. As with humans, the steam and moisture can help with clogged sinuses.

Whenever things look like they are getting worse, it is good to at least call your vet and ask an opinion. With young kittens things can become life threatening quickly. Your vet can let you know if it sounds like you should bring him back in.

Gook luck and let us know how it turns out.

Stephanie in Montreal


William Draper, DVM, better known as "Dr. Will," is a well-known small animal practitioner in the Atlanta, GA area. He grew up in Inglewood,...More

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