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Lysine for Cats?

Lucian

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Jan 26, 2009
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3,257
I was going to start a thread on this subject on Saturday when my interest was purely academic, but I didn't. Now I have a more invested interest.

A couple of weeks ago when I was doing my volunteer job cleaning cages at an adoption center, there was a note that one of the kittens was supposed to get Viralys gel twice a day for the duration of his stay. He had been sneezing, and one of his sisters had had an eye infection.

So I got the tube and looked at it to see what it was and what it was for. There wasn't much information, but based on the name, I guessed it was for viruses. When I saw that it was a supplement, I thought, "Hmmm" and determined to look it and its active ingredient, lysine, up when I got home. Of course, I forgot.

But this Saturday, I had to give him the Viralys again, and I did remember to look it up. I found out that lysine is an essential amino acid. Since the body doesn't produce it, it has to be absorbed by food. I assumed, though, that commercial cat foods would have sufficient lysine in them. I discovered that it is supposed to help cats who have colds, runny eyes or other problems related to feline herpes. I didn't see any definitive evidence that the supplement actually does anything, but a lot of perfectly respectable vets seem to prescribe it.

Then on Sunday, we got adopted by a cat. He was wandering about our apartment complex's parking lot, meowing for attention. No collar or tags. We took him to the emergency vet to be scanned for a microchip, but he didn't have one. He has been neutered, though. We put up fliers and checked lost pet classifieds (very depressing). No luck. We took him to the Humane Society on Monday, but they were full.

We started to think about keeping him because he is the sweetest mammal ever. He won't eat or drink water until he's had a good cuddle first. He crawls into my arms and just purrs and purrs and kneads and kneads.

He had a slightly runny eye on Sunday, which seemed better on Monday. Today we took him to the vet to get checked for FIV/FeLV (negative--yay), get shots and a general check-up. They were going to test for parasites, but they couldn't get a sample out of him, so they wormed him anyway.

As soon as we put him in the carrier to go to the vet, his eye started running again. The discharge is clear and there doesn't seem to be any major inflammation. The vet did check to see if he had a scratch on his cornea (the magic glowing goop test). He didn't. She said it could be herpes, triggered by stress. She said we should just pay attention and call if it got worse. And she prescribed Viralys granules to keep "the virus from replicating."

So, the short version of my long-winded question is: does a lysine supplement actually do anything? Does it suppress the virus? Or is it woo?

Also, any suggestions for names? Right now the candidates are Gavin McLoud (he doesn't like being alone and is not shy about saying so) and Ragnar Hairy-britches.
 
My understanding is that lysine is a legitemate treatment for persistent FHV-1 outbreaks in domestic cats.

Administering lysine appears to be correlated with reduced clinical signs and reduced viral shedding.

  • Maggs, D. J., Nasisse, M. P. & Kass, P. H. (2003) Efficacy of oral supplementation with L-lysine in cats latently infected with feline herpesvirus. Am. J. Vet. Res. 64: 37–42.[Medline]
  • Stiles, J., Townsend, W. M., Rogers, Q. R. & Krohne, S. G. (2002) Effect of oral administration of L-lysine on conjunctivitis caused by feline herpesvirus in cats. Am. J. Vet. Res. 63: 99–103.[Medline]

Mechanism of action is unproven, but hypothesized to be reduced viral replication due to antagonism of arginine by excess lysine. FHV-1 requires arginine to replicate.


ETA: sounds like you have a great cat. If you're thinking Gavin McLoud, why not name him "Captain Stubing"? He sounds like a cat who could be in charge of the Luuuuve Booooat.
 
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My understanding is that lysine is a legitemate treatment for persistent FHV-1 outbreaks in domestic cats.

Administering lysine appears to be correlated with reduced clinical signs and reduced viral shedding.

  • Maggs, D. J., Nasisse, M. P. & Kass, P. H. (2003) Efficacy of oral supplementation with L-lysine in cats latently infected with feline herpesvirus. Am. J. Vet. Res. 64: 37–42.[Medline]]
  • Stiles, J., Townsend, W. M., Rogers, Q. R. & Krohne, S. G. (2002) Effect of oral administration of L-lysine on conjunctivitis caused by feline herpesvirus in cats. Am. J. Vet. Res. 63: 99–103.[Medline]]

Mechanism of action is unproven, but hypothesized to be reduced viral replication due to antagonism of arginine by excess lysine. FHV-1 requires arginine to replicate.


ETA: sounds like you have a great cat. If you're thinking Gavin McLoud, why not name him "Captain Stubing"? He sounds like a cat who could be in charge of the Luuuuve Booooat.

Thanks for the information--good to know.

The name has evolved. It started when I took a picture of him to put on "found cat" posters. I named the file "Mr. McLoud" because he was being very loud. Then it was Gavin McLoud. Then we thought of Mystery Science Theater where they say, "Chief," "McCloud" in reference to the Dennis Weaver show from the 70s. Currently, he's "Gavin" at the vet's, but it's written in pencil, so we can change it.

We just locked the incumbent cats up and let the-cat-to-be-named-later out of the bathroom to wander about a bit, and it looks as if he has red eye-shine. My white, blue-eyed Siamese mix has red eye-shine, but Cat X is a brown tabby with greenish eyes. Odd.
 
My understanding is that lysine is a legitemate treatment for persistent FHV-1 outbreaks in domestic cats.

Administering lysine appears to be correlated with reduced clinical signs and reduced viral shedding.

  • Maggs, D. J., Nasisse, M. P. & Kass, P. H. (2003) Efficacy of oral supplementation with L-lysine in cats latently infected with feline herpesvirus. Am. J. Vet. Res. 64: 37–42.[Medline]
  • Stiles, J., Townsend, W. M., Rogers, Q. R. & Krohne, S. G. (2002) Effect of oral administration of L-lysine on conjunctivitis caused by feline herpesvirus in cats. Am. J. Vet. Res. 63: 99–103.[Medline]
Mechanism of action is unproven, but hypothesized to be reduced viral replication due to antagonism of arginine by excess lysine. FHV-1 requires arginine to replicate.


Well, there you go. That's what I get for not keeping up with the literature.

Rolfe.
 
We were given lysine to treat our cats, the vet told us the virus couldn't use that form (L, I think) but the cat could. Dosing the cat with lysine of only one isomer would starve the virus without hurting the cat.
 
We were given lysine to treat our cats, the vet told us the virus couldn't use that form (L, I think) but the cat could. Dosing the cat with lysine of only one isomer would starve the virus without hurting the cat.



I had an emergency vet visit last night, and they suggested a lysine supplement to control her sneezing problem, as well as my other cat's eye problems that I mentioned while they were taking her history. This sounds like the explanation I received as well.

And for once, it seems they were right about the cats liking the taste. I had to stop the one cat from eating the other cat's share!
 
Thanks for the information--good to know.

The name has evolved. It started when I took a picture of him to put on "found cat" posters. I named the file "Mr. McLoud" because he was being very loud. Then it was Gavin McLoud. Then we thought of Mystery Science Theater where they say, "Chief," "McCloud" in reference to the Dennis Weaver show from the 70s. Currently, he's "Gavin" at the vet's, but it's written in pencil, so we can change it.

Gavin will do just fine, though when I read it at first I was thinking more Love Boat than cowboy in the city.
 

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