Dear George,
I must say…THIS IS the advantage of our “color”-
sometimes …we can go undercover or….notoriously unnoticed.
We can act as the “eyes and ears” of a spy
agency or a hidden camera for different purposes! (see the photo attached) But
the reason I’m writing to you today is actually to get your secretary’s advice concerning
a health issue of one of my friends.
I know she’s busy with her exams but one of
my friends has an eye problem – his eyes gets “tears stain” without any eye
infection or anything. The tears are not clear either; the tears/stains are
reddish/brown and are bothering him only once in a while.
His vet put him first on an antibiotic
unguent that did nothing and then on Lysine.
Is he safe to be on Lysine for the rest of
his life? Any idea? Even while on Lysine the tears stains come back once in a
while. Any other cat that had this problem? Any explanation why is this
happening?
Grateful (on behalf of my friend)
Bentley
Dear Bentley,
Humans occasionally, very occasionally, are useful. Celia, whose studies I find extremely irritating, nevertheless was able to research several papers about Lysine. Apparently about 90% of animal hospitals in the USA, UK and Australia give Lysine to cats that have the Feline Herpes Virus 1 (FHV1). FHV1 causes "goopy eye" in cats, stays in the body life long and like cold sores in humans is likely to surface during times of stress.
The theory of giving Lysine, a food supplement, was that it reduced arginine levels, an amino acid, which in turn reduced the herpes virus's ability to reproduce. Thus cats treated with Lysine shed less virus and would recover faster. It's a great idea. And because an attack of FHV (like cold sores) usually goes away eventually anyway, vets thought it was the Lysine that was working.
But it doesn't work. In practice it makes no difference at all. The latest scientific paper on this drug says it is ineffective and should not be used (details in a PS). This isn't just because it doesn't work, it is because cats need arginine, an essential amino acid. So lowering the level of arginine may be bad for the cat's health. I suggest Bentley gets his human to find the full paper on Google Scholar, downloads it, and shows it to his vet.
It looks as if it would be better for Bentley's humans to concentrate on giving him a stress free life (look here). He needs good nutrition, lots of interesting things to do (look here) if he is an indoor-only cat, a settled routine, and sensitivity to how much affection he wants from humans.
Yours
George.
PS.
Lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats: a systematic review
Dear Bentley,
Humans occasionally, very occasionally, are useful. Celia, whose studies I find extremely irritating, nevertheless was able to research several papers about Lysine. Apparently about 90% of animal hospitals in the USA, UK and Australia give Lysine to cats that have the Feline Herpes Virus 1 (FHV1). FHV1 causes "goopy eye" in cats, stays in the body life long and like cold sores in humans is likely to surface during times of stress.
The theory of giving Lysine, a food supplement, was that it reduced arginine levels, an amino acid, which in turn reduced the herpes virus's ability to reproduce. Thus cats treated with Lysine shed less virus and would recover faster. It's a great idea. And because an attack of FHV (like cold sores) usually goes away eventually anyway, vets thought it was the Lysine that was working.
But it doesn't work. In practice it makes no difference at all. The latest scientific paper on this drug says it is ineffective and should not be used (details in a PS). This isn't just because it doesn't work, it is because cats need arginine, an essential amino acid. So lowering the level of arginine may be bad for the cat's health. I suggest Bentley gets his human to find the full paper on Google Scholar, downloads it, and shows it to his vet.
It looks as if it would be better for Bentley's humans to concentrate on giving him a stress free life (look here). He needs good nutrition, lots of interesting things to do (look here) if he is an indoor-only cat, a settled routine, and sensitivity to how much affection he wants from humans.
Yours
George.
PS.
Lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats: a systematic review
Bol and Bunnik BMC Veterinary Research (2015) 11:284
Abstract
Background: Feline herpesvirus 1 is a highly contagious virus that affects many cats. Virus infection presents with flu-like signs and irritation of ocular and nasal regions. While cats can recover from active infections without medical treatment, examination by a veterinarian is recommended. Lysine supplementation appears to be a popular intervention (recommended by > 90 % of veterinarians in cat hospitals). We investigated the scientific merit of lysine supplementation by systematically reviewing all relevant literature.
Methods: NCBI’s PubMed database was used to search for published work on lysine and feline herpesvirus 1, as well as lysine and human herpesvirus 1. Seven studies on lysine and feline herpesvirus 1 (two in vitro studies and
5 studies with cats), and 10 publications on lysine and human herpesvirus 1 (three in vitro studies and 7 clinical trials) were included for qualitative analysis.
Results: There is evidence at multiple levels that lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats. Lysine does not have any antiviral properties, but is believed
to act by lowering arginine levels. However, lysine does not antagonize arginine in cats, and evidence that low intracellular arginine concentrations would inhibit viral replication is lacking. Furthermore, lowering arginine levels is highly undesirable since cats cannot synthesize this amino acid themselves. Arginine deficiency will result in hyperammonemia, which may be fatal. In vitro studies with feline herpesvirus 1 showed that lysine has no effect on the replication kinetics of the virus. Finally, and most importantly, several clinical studies with cats have shown that lysine is not effective for the prevention or the treatment of feline herpesvirus 1 infection, and some even reported increased infection frequency and disease severity in cats receiving lysine supplementation.
Conclusion: We recommend an immediate stop of lysine supplementation because of the complete lack of any scientific evidence for its efficacy.
Background: Feline herpesvirus 1 is a highly contagious virus that affects many cats. Virus infection presents with flu-like signs and irritation of ocular and nasal regions. While cats can recover from active infections without medical treatment, examination by a veterinarian is recommended. Lysine supplementation appears to be a popular intervention (recommended by > 90 % of veterinarians in cat hospitals). We investigated the scientific merit of lysine supplementation by systematically reviewing all relevant literature.
Methods: NCBI’s PubMed database was used to search for published work on lysine and feline herpesvirus 1, as well as lysine and human herpesvirus 1. Seven studies on lysine and feline herpesvirus 1 (two in vitro studies and
5 studies with cats), and 10 publications on lysine and human herpesvirus 1 (three in vitro studies and 7 clinical trials) were included for qualitative analysis.
Results: There is evidence at multiple levels that lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats. Lysine does not have any antiviral properties, but is believed
to act by lowering arginine levels. However, lysine does not antagonize arginine in cats, and evidence that low intracellular arginine concentrations would inhibit viral replication is lacking. Furthermore, lowering arginine levels is highly undesirable since cats cannot synthesize this amino acid themselves. Arginine deficiency will result in hyperammonemia, which may be fatal. In vitro studies with feline herpesvirus 1 showed that lysine has no effect on the replication kinetics of the virus. Finally, and most importantly, several clinical studies with cats have shown that lysine is not effective for the prevention or the treatment of feline herpesvirus 1 infection, and some even reported increased infection frequency and disease severity in cats receiving lysine supplementation.
Conclusion: We recommend an immediate stop of lysine supplementation because of the complete lack of any scientific evidence for its efficacy.
Most helpful! Thanks George for giving Celia permission to reply!
ReplyDeleteThanks Celia - your answer is a life saver :-)
Bentley (on behalf of my friend)
Interesting! Guess....this should be read by all vets in the USA. I just read on the Little Big Cat website that Lysine is safe! Hmmm! Any alternatives to it?
ReplyDeleteTom
Gweat advice George, and ifin it's just da ugly brown tear stains dat be botherin' them, then there are lots of purroducts on da market to take those away. have a pawsum day.
ReplyDeleteLuv ya'
Dezi and Lexi
This is IMPORTANT advice. Thanks so very much for informing us all 'bout this study. purrs
ReplyDelete