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  6. Felisyl Immune System Support Granules - 3-PACK (10.5 oz)


Felisyl Immune System Support Granules - 3-PACK (10.5 oz)

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Felisyl® is a supplement that contains the amino acid L-Lysine for use in cats and kittens for conditions responsive to L-Lysine. L-Lysine is an essential amino acid, which means that your catís body needs it, but canít produce it, so this supplement is a perfect choice to provide that necessity.

L-Lysine HCL Immune System Support for Cats helps keep your cat healthy by supporting the immune system naturally so that it can function normally and produce antibodies. Felisyl L-Lysine HCL Immune System Support for Cats also helps maintain healthy tissue, supports respiratory health, and may even help with your catís vision. The L-Lysine is in palatable poultry, and the flavored fish base was making these granules easy to give to your cat, sprinkle over or mix with food.


L-Lysine HCI 250mg

Ingredients: L-Lysine in a palatable base

Useful Information

Approximately 250mg of L-Lysine per one rounded scoop (322mg)

Kittens under 6 months: ½ Scoop twice Daily

Cats older than 6 months: 1 scoop twice daily

Store in a cool, dry place, out of the reach of children. Keep tightly shut to preserve freshness.

Customer Reviews

28 Reviews
71% (20)
18% (5)
11% (3)
0% (0)
0% (0)
93% Recommend this product (26 of 28 responses)
By ChristineP
Dover, NJ
July 16, 2017
My cats would not eat their food with this added. Bought 3 jars, unfortunately threw out the shipping receipt so I can't return it. Will have to order the other brand.
By Cease
Northern Colorado
May 7, 2017
Seems to be a good product
Felisyl seems to help keep in check the stomatitis virus two of my cats have. Combined with Geneflora, we have managed to not have to have our cats teeth extracted, a very costly procedure. I would recommend only mixing with fish canned food as they didn't like it mixed in with poultry or beef canned food, bc it is fish flavored.
By snoopy26??
July 21, 2016
great product
I have 2 cats with chronic URI so I put some in their canned food each night and they all eat it with no issues. I believe it helps them.
By Pam
Clinton, TN
December 17, 2015
Good results so far
Purchased this product for a friend who is fostering a feral momma cat and her kittens. The momma suffers from a herpes virus that was very severe in her eyes. This product seems to have cleared it up within days. We had to try something that could be added to her food since she can not be held and given meds.
By Max's m.
Atlanta, GA
September 15, 2015
good product
I have 3 cats, 2 with feline herpes. the lysine really helps keep the herpes respiratory virus under control and avoid rounds of antibiotics for the cats.
July 24, 2015
Works well and more economical
Felisyl (L-Lysine) immune system support is effective in controlling symptoms of feline herpes (e.g. eye discharge, sneezing) among those cats of ours showing these signs. The product is readily ingested by our cats when we mix it with their morning and evening wet food. When we miss a day or two, the symptoms return but are quickly resolved upon resuming the dosages. At the recommended dosage, Felisyl is more economical to use than other equally effective l-lysine products.
By Ty
June 14, 2015
Love it
Delivered very prompt always, only place we get our cats products. Thanks for your great prices also. Ty
By CatLady51
Lima, Peru
May 15, 2015
My cats don't like it!
To my dismay, my cats do not like the product. They deliberatedly leave the wet food that has it!
Too bad,
By Lee
April 16, 2015
No smell at all - great for hiding in food
Was pleasantly surprised when I opened the container to find there was no smell to the powder crystals. The product this was comparable to has a nasty dead fish smell. This one did not. Thank you for a great product.
By Kim
April 14, 2015
Cats love it
I've tried the chew treats and my cats hate them. This I mix in their wet food every morning and they eat it right up. Theirs eyes have cleared up and the sneezing is to a minimum.
By vnapper
March 20, 2015
Great for Feline AIDS kitty
I add this powder to all of my kitty's food. It helps keep their immune system up and prevent problems. I have a Feline AIDS positive kitty who gets this in all of his meals. I really notice a difference in his breathing (wheezing) and his overall playfulness. I also add this to my other kitty who has an eye infection and it helps her fight that. Great stuff.
Northern Illinois
March 3, 2015
Great Supplement
I purchased Felisyl Immune System Support for my newly adopted elderly kitty (12 years old), who has extreme allergies. I switched her from all food with wheat and corn, added Omega 3 oil to her wet food for her very dry skin, and am adding the Lysine supplement to her diet in hopes of keeping her allergies at bay. She hasn't been on it very long, but I'm looking at the long term for her. The first week she was here, she nearly literally choked to death on the copious phlegm in her throat. The vet told me to use children's Benadryl to help her out, and that seems to help, but I want her off meds if at all possible. The lysine will help with her immunity and it's also something the vet suggested. I'm looking forward to a healthy kitty now!
By Teddy's m.
Northern California
February 16, 2015
Good product
This supplement was recommended for my cats. They seem to like this brand better than the one I purchased at the vet. The price is better too.
By Kazuye
Los Angeles
August 17, 2014
My cat caught the herpes virus while a kitten at the animal shelter. Felisyl helps her from getting so much sneezing and stuffy nose symptoms. I mix it into her food everyday and she doesn't mind it at all.
By dustyj
austin, TX
February 26, 2014
great product
I have a cat with a chronically irritated eye and she is also FIV positive. My veterinarian had suggested l-lysine to help decrease the viral load and she suggested this. I sprinkle some on a bit of wet food or spray water on her dry food and sprinkle some on it. She gets her doses twice a day - no hassle.
By mindymoon
December 14, 2013
not just for feline herpes
I took in a very sick stray 3 years ago He had an upper respiratory infection so severe that 3 different vets weren't sure he would make it. He also tested positive for Feline HIV. Vet suggested Viralys for immune support. I've had him on Felisyl for 3 years. After months of TLC and antibiotics, he got healthy and gained weight. His coat is beautiful, eyes and ears clear. And he has stayed very healthy since. I think the Felisyl helps, so will continue it for the rest of his life. I add a scoop to his wet food once a day.
By cati
August 7, 2013
Excellent purchase price
This L-Lysine HCI supplement for cats is less expensive than the vet recommended Viralys. So far, it has been just as effective to address herpes in my cats. The best part about Felisyl is that the cats actually eat it readily when mixed with canned cat food.
By I n.
North Carolina
July 1, 2013
Felisyl Immune System Support
The cats like it, Use it to help keep foster kitties healthy.
By DustyJ
elgin tx
June 15, 2013
Great product
Cats like the lysine powder (all 9 of them) - a first! easy to put on wet or dry food. I use a slight spray mist of water which helps the powder stay attached to the dry food and voila it is eaten without problems
By Kazi's M.
June 7, 2013
Review for Felisyl Immune System Support Granules - 3-PACK (10.5 oz)
This product has done a good job keeping my kitties from having feline herpes return. It is a good immune system builder.
By annetta
March 29, 2013
This is Great Stuff!
Felisyl helps the immune system of cats. My cats have frequent sneezing and it takes care of it. Likely the vet said it's probably from cat herpes. But many cats have this. Any time a respitory problem...cold or stuff like that starts...give them felisyl. It's best to not give daily unless your cat has a severe or ongoing problem. It works for my babies and it may likely make your vet trips much less needed.
By Tutti
Los Angeles
February 6, 2013
Felisyl recommended by my vet
Great product especially for those of us that have more than 1 cat because you can use it every day in their food and it strengthens their ammune system. I am on my 4th container. Entirely Pets has the best price according to my vet.
By Tuxcats
December 17, 2012
good value
There are other L-Lysine products, same ingredients, at a higher cost, on the market, and at the Vet's office. Happy with product, price, and great service.
By vj
December 14, 2012
Very nice product
My cats must like the taste because they eat it up when I sprinkle it on their food!
By fostercatmom
Indianapolis, IN
August 19, 2012
great stuff
I have volunteered with an animal shelter for over 10 years. We put lysine on the food of all the cats because it helps with the herpes virus that runs through all shelters. It doesn't cure the virus, just helps to keep it from replicating. This version is flavored and the cats like it.
Essex County, NJ
April 10, 2012
Good Supplement for Those Who Need It
My vet told me to add lysine to my cat's food. He had a herpes infection when I rescued him. The lysine is supposed to help recurrences and thus far Simon has had none.

I mix the Felisyl with his wet food and he seems quite willing to eat it. It's easy to use and one jar lasts for a couple of months. Good product.
By Cat L.
March 23, 2012
Review for Felisyl Immune System Support Granules - 3-PACK (10.5 oz)
Have had the cats on this for years to keep down the symptoms of the kitty herpes type illness. They like the taste and it works well. Much easier to use than the paste and more economical too.
By MaryAnnSanDiego
San Diego, CA
July 6, 2011
My cat liked the Viralys better
I had been using the Viralys powder for about a year with no problem. Just decided to try the Felisyl since it was a little cheaper. My cat backs away from ANY food I put down with the Felisyl mixed in. Eventually after complaining for a while, she will eat! I will go back to the Viralys so I won't have any food issues. Both products seem to work the same, however.

Questions and Answers

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