The Lysine Myth For Fcv1 And Prevention Of Respiratory Ailments

[Faikey]

Hello! I just spent hours researching something after a poster suggested using l-lysine as a way to control the cats feline herpes.
1) Most studies supporting the increased use or supplementation of lysine were all completed with small sample sizes and funded by either herbal organizations of pet food organizations! I could not find a large scale study that actually gave valid scientific evidence that there was even a benefit for additional lysine than what was already required in cat food.

2)A large scale study explored the health benefits of using L-Lysine as a way to help FCV1 and upper respitory ailaments. They found absolutely no proof that Lysine helped at all. In fact, they stated that the supplementation of lysine should be stopped completely as it is completely unnecessary .

I bring this up as Ive seen so many people recommend this treatment without knowing its lack of actual proof in felines. And I was shocked further when I couldn't find a single scientific study that was done without bias or funding from a larger company that even supported the idea that lysine was this miracle amino acid. Most doctors recommend it due to simple anecdotel evidence which include biases from people assuming this works from google articles and doctors even assume it works from patients just claiming it does despite it having NO basis in science.


"bmcvetres.biomedcentral.com
Lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats: a systematic review
Sebastiaan Bol, Evelien M Bunnik
BMC veterinary research 11 (1), 284, 2015
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. 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. 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. We recommend an immediate stop of lysine supplementation because of the complete lack of any scientific evidence for its efficacy."

Lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats: a systematic review

 

[She's a witch]

Lysine might not be effective in preventing and treating FHV, but it did help relieve chronic symptoms in my FHV and FCV cats. My vet told me to stop supplementing if symptoms worsen. She also told me that although theoretically possible, allegedly arginine deficiency was not confirmed in practice with lysine supplementation.

Some people here use bovine lactoferrin with good results. I currently use probiotics which completely stopped the symptoms.

 

[Faikey]

Lysine might not be effective in preventing and treating FHV, but it did help relieve chronic symptoms in my FHV and FCV cats. My vet told me to stop supplementing if symptoms worsen. She also told me that although theoretically possible, allegedly arginine deficiency was not confirmed in practice with lysine supplementation.

Some people here use bovine lactoferrin with good results. I currently use probiotics which completely stopped the symptoms.

This study is what you're mentioning regarding the dangers of lysine and arginine: Excess Dietary Lysine Does Not Cause Lysine-Arginine Antagonism in Adult Cats
But you can tell the study was very inconclusive. It uses references dating back to 1966. They even admit several faults of the study, and major conflicts in biases due to who funded this study: Waltham Inc, a major manufacturer of supplements and cat/dog food. The study was also funded by Purina and further edited by UC. This study literally had no conclusion.

I actually quoted the study directly but perhaps you should read the whole thing which is quite broad an covers dozens upon dozens of studies before reaching a conclusion:
Lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats: a systematic review

Then a PetMD vet also published this as a result:
The Usefulness of Lysine Supplements for Cats Under Scrutiny | petMD


"Some cats have intermittent flare-ups of eye, upper respiratory, and/or skin problems. These may be associated with times of stress, or they may seem to occur completely at random. In the worst cases, individuals suffer from unrelenting symptoms that have a significant impact on their quality of life.

It’s not too surprising then that owners (and veterinarians) are looking for something—anything—to help cats with chronic herpesvirus infections. Supplementing a cat’s diet with the amino acid lysine has been popular for a long time now. I’ve recommended it myself, even though I had never seen definitive scientific proof that it is helpful.

Turns out there’s a good reason why I have never run across that evidence. It doesn’t exist.

In a recent study, two scientists searched the literature for “published work on lysine and feline herpesvirus 1, as well as lysine and human herpesvirus 1.” They included 17 studies in their review and found the following:

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.


It will be hard for me to continue to endorse the use of lysine in the face of this recent article. I guess I’ll now have to lean more heavily on my other recommendations:

• Practice aggressive preventative medicine and treat any health conditions that do develop quickly to avoid “distracting” the immune system

• Treat especially severe flare ups with antiviral medications and secondary bacterial infections with antibiotics

• Reduce exposure to whatever is stressful for the infected cat

• And most importantly, provide excellent overall nutrition to support the immune system

Dr. Jennifer Coates"

 

[PushPurrCatPaws]

Faikey - totally agree.

I myself have a hard time seeing l-lysine continuing to be recommended.

The rescue shelter I got my cat from was very reliant upon the use of l-lysine. I am not saying anything bad about the rescue, but I guess I just worried that this mindset they had, that lysine is so helpful to an FHV-1 cat/kitten, may have made the rescue maintain a false sense of "security" that the sick cat was definitely being helped -- and, in so doing, staff didn't work more on other factors that may have decreased the spread of feline herpes (e.g. or maybe I mean, doing more to decrease flare-ups in already-sick kittens/cats, like working with stress levels and giving better nutrition, etc).

A few years back, this thread here talked about the same issue...
Supplementing with Lysine NOT recommended for Herpes Kitties

And although (as with all sources I try to read) I try using scepticism when reading even this author's writings (some things I agree with and appreciate; some things I don't), this blog post was from a year ago -
Lysine for Feline Herpesvirus: A Therapeutic Zombie | The SkeptVet

 

[Faikey]

Faikey - totally agree.

I myself have a hard time seeing l-lysine continuing to be recommended.

The rescue shelter I got my cat from was very reliant upon the use of l-lysine. I am not saying anything bad about the rescue, but I guess I just worried that this mindset they had, that lysine is so helpful to an FHV-1 cat/kitten, may have made the rescue maintain a false sense of "security" that the sick cat was definitely being helped -- and, in so doing, staff didn't work more on other factors that may have decreased the spread of feline herpes (e.g. or, maybe I mean doing more to decrease flare-ups in already-sick kittens/cats, like working with stress levels and giving better nutrition, etc).

A few years back, this thread here talked about the same issue...
Supplementing with Lysine NOT recommended for Herpes Kitties

And although (as with all sources I try to read) I try using scepticism when reading even this author's writings (some things I agree with and appreciate; some things I don't), this blog post was from a year ago -
Lysine for Feline Herpesvirus: A Therapeutic Zombie | The SkeptVet

I see you went around and researched too. They found that in shelters lysine actually increased the chance of fsv and increased its severity. There was a study they cited among the 60 or so they cited that went into further detail

 

[Faikey]

I'm a scientist (ferreals!) I majored in chemistry so valid research is what I strived for before posting. I think I went through hundreds of articles and their sources to find how little research was ever done on effectiveness of lysine

 

[stephanietx]

I know there is scientific evidence that says it doesn't work, but I have given my herpes girl Lysine for 10 years. When she goes off it, symptoms recur. I don't think it "cures" herpes, but I do believe it helps boost the immune system and that's a win in my book.

 

[She's a witch]

I know there is scientific evidence that says it doesn't work, but I have given my herpes girl Lysine for 10 years. When she goes off it, symptoms recur. I don't think it "cures" herpes, but I do believe it helps boost the immune system and that's a win in my book.

Yeah i think most people who recommend lysine know it doesn’t treat herpes but only masks the symptoms. But let’s face it, sometimes it is already a lot. My cat is rather uncomfortable when he has a watery eye, he comes asking to wipe it down so lysine was useful to raise his comfort level.

Nothing cures herpes as for now so people use whatever they know may relieve the symptoms. There are no many alternatives. I’m glad that probiotics work in my cats’ case but will I read in few years time that it is possibly harmful to cats? Maybe.

 

[bear]

PushPurrCatPaws
Having volunteered with rescues, I would not automatically think that suggesting Lysine ruled out their primary treatment of looking for multiple ways to reduce stress. I have seen lots of transfers to foster homes with isolation areas of the home for FHV cats that reduce stress of being near other cats. I have seen limitations for the number of days in adoption centers for selected FHV (and other stressed) felines. This might be something like "no longer than 14 days, or return to foster home for a break.

 

[PushPurrCatPaws]

bear , that is good to hear. It will probably depend on the capacities of the particular rescue, in terms of money, space, available foster homes and the like.

 

[cheeser]

I know there is scientific evidence that says it doesn't work, but I have given my herpes girl Lysine for 10 years. When she goes off it, symptoms recur. I don't think it "cures" herpes, but I do believe it helps boost the immune system and that's a win in my book.

We're read many similar articles about how L-lysine isn't as effective as once thought, but our FHV/FIV kitty hasn't.

 

[bear]

I have not used Lysine to control outbreaks in my herpes cats.
Instead I look at removing stress generators. In the past, this has included keeping two cats on different sides of glass doors for 9 years.

The question now becomes:
What about stress in felines causes the amino acid arginine to increase. This increase is believed to activate herpes virus enough to cause outbreaks.

====
A human reference from herpes.org follows:
herpes.org/10-things-you-need-to-know-about-preventing-outbreaks-without-drugs
"Arginine, like lysine, is one of the eight important amino acids. Foods such as peanuts, chocolate, raisins, some grains, especially wheat they have twice as much arginine as lysine. Too much arginine can trigger an outbreak because the herpes virus needs arginine to in order to grow and multiply."
====

I keep my chocolate covered peanuts and raisins for myself!
Notice the reference to grains?
Not sure if that also applies to felines.
I know that the Ex would have cold sore flair ups from excess sun. That was not food induced. Could excess sun cause stress in humans? Possibly a same or similar reaction.

 

[Faikey]

The study was very specific on lysine affects on different animals. The thing is that most of you are experiencing obvious success because your cat will eventually have the flare ups go down naturally and you're simply coinciding it was actual evidence which it isn't. I posted actual studies with extensive research. I only posted to share knowledge. Will your cat die from lysine supplementation? No. I know anecdotal evidence is easier to believe than actual scientific studies. And because no study has actually been conclusive on the dangers of too much lysine I can't say that it'll hurt them. Lysine doesn't work with cats as it does with humans. We metabolize it much differently.

 

[2furbabies]

I had been using Lysine for my Persians for 20+ years. I recently had an Ophthalmologist appt for my Persian who has an eye issue and we got to talking about Lysine. She too said there were no large studies until recently, and the large study that was conducted showed there are no benefits to Lysine. She told me I could stop using it, which I did.

 

[Faikey]

I have not used Lysine to control outbreaks in my herpes cats.
Instead I look at removing stress generators. In the past, this has included keeping two cats on different sides of glass doors for 9 years.

The question now becomes:
What about stress in felines causes the amino acid arginine to increase. This increase is believed to activate herpes virus enough to cause outbreaks.

====
A human reference from herpes.org follows:
herpes.org/10-things-you-need-to-know-about-preventing-outbreaks-without-drugs
"Arginine, like lysine, is one of the eight important amino acids. Foods such as peanuts, chocolate, raisins, some grains, especially wheat they have twice as much arginine as lysine. Too much arginine can trigger an outbreak because the herpes virus needs arginine to in order to grow and multiply."
====

I keep my chocolate covered peanuts and raisins for myself!
Notice the reference to grains?
Not sure if that also applies to felines.
I know that the Ex would have cold sore flair ups from excess sun. That was not food induced. Could excess sun cause stress in humans? Possibly a same or similar reaction.

Lysine doesn't work the same way as it does in humans as in felines. They discussed this pretty thoroughly.

In fact the study discusses both human and feline. "Lysine does not antagonize arginine in cats" as it does with humans. As in, yes humans and felines are different. In Pigs and Chickens lysine created rather bad results. But this stuff is all different.

 

[bear]

There is no information in the article that I read suggesting the arginine increases are not at the cause of the flair ups.

 

[Faikey]

There is no information in the article that I read suggesting the arginine increases are not at the cause of the flair ups.

Super confused here. The article was strictly about how lysine does not affect FHV like it affects HPV because it's lack of antagonistic properties but too much arginine doesn't increase flare ups? it's an essential amino acid cats can't produce themselves. All I could find is that it's important cats get arginine. I couldn't find a good clinical study discussing what you're bringing up

 

[bear]

Maybe you are looking at only one of the links or I linked to others in the report.

The one I spent the most time in suggested that they used cat feline herpes virus cells to test the effects of arginine when lysine was added. They did not find that the arginine was reduced by the addition of lysine.

I did notice that they appeared to not consider if lysine in a feline might be a catalyst for another part of the cat, that would result in the reduction of arginine. I haven't promoted lysine in cats, yet the study with just three components in a test tube, doesn't rule out other interactions if other components (including chemicals) or systems of a cat are involved.

Other than that, my comments on arginine possibly increasing as a result of feline stress to trigger attacks is worth considering looking into by those researching feline herpes virus.

 

[bear]

A well known local Vet, was working about 8 years ago with stem cell repair of selected parts of equines and canines. I made a connection for the company she was at with a company that was interested in funding studies to help felines. I have not heard if that connection was fruitful for them and felines. I do know that she is back practicing locally again. Possibly I can run my thoughts by her.

 

[Faikey]

A well known local Vet, was working about 8 years ago with stem cell repair of selected parts of equines and canines. I made a connection for the company she was at with a company that was interested in funding studies to help felines. I have not heard if that connection was fruitful for them and felines. I do know that she is back practicing locally again. Possibly I can run my thoughts by her.

Oh I see. Excess lysine does drop arginine levels in the blood low for a brief period of time if ingested through powder supplements and only suggests hyperammonemia as a severe result of too much lysine. Arginine isnt produced by cats naturally so for it be a result of stress would be interesting because..they aren't able make it themselves (at least not without some help with my understanding). I do know they did develop a drug similar to vacolyir (spelling?) The human hcv drug for 1 and 2 and shingles and that fun stuff that showed some promise but that's all I've seen.