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  6. 3-PACK Felisyl Immune System Support (180 Soft Chews)


3-PACK Felisyl Immune System Support (180 Soft Chews)

Item: 5939-3PK
Compare to: $50.99
You Save: $23.00!(45%)

NASC Certified

This product has met all of the stringent quality and safety standards set by the NASC.

The NASC (National Animal Supplement Council) is a non-profit self regulatory group that set specific guidelines to which manufactures must strictly adhere.

This seal is meant to minimize risk by providing an easy way of communicating to consumers that a product and its manufacturer meet particular standards of quality, customer safety and service.

Those products that have the seal for NASC Quality and Safety standards have been strictly audited and were determined as meeting the following criteria:

  • Consistent manufacturing quality control
  • A system for evaluating complaints and adverse events
  • Clear and accurate labels compliant with codes and restrictions for all forms of labeling


Felisyl® is a soft chew 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 pet's body needs it, but can't 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 Soft Chews for Cats also helps maintain healthy tissue, supports respiratory health, and may even help with your cat's vision. The L-Lysine is in a chicken liver flavored soft chew making it easy to give to your cat.

For Use In: Cats


Guaranteed Analysis per Chew (1.5g):
Moisture (max) 11.1%
L-Lysine 250 mg

Ingredients: l-lysine, natural chicken liver flavor, oat flour, rye four, soy lecithin, brewers dried yeast, water, arabic gum, glycerin, canola oil, maltodextrin, sodium alginate, calcium sulfate, citrus pectin, oat meal, sorbic acid (a preservative), propionic acid (a preservative), mixed tocopherols (a preservative).

Useful Information

Give 1-2 chews daily

WARNINGS: For animal use only.

Store in a cool dry place.

Keep out of reach of children and animals. Your pet may consider this a treat. In case of accidental overdose, contact a healthcare professional immediately.

Customer Reviews

13 Reviews
62% (8)
23% (3)
8% (1)
0% (0)
8% (1)
85% Recommend this product (11 of 13 responses)
By Jan
Rural Hall, NC
April 12, 2016
Excellent supplement
My finicky Siamese loves the taste of these treats! Great value!
By Callie's M.
Napa, California
February 15, 2016
Good for Cat Health
Like these a lot, but only one of my cats will eat them.
By MerryMari
January 31, 2016
Lysine is good, but cat won't eat it
I think the Lysine has been helpful in reducing my cat's symptoms. However, this cat will eat ANYTHING...except this! I have to break up the pieces into little bits and stuff them ino her canned meat. She still resists, eating around the bits most of the time. I will try a different brand of Lysine and hope she will eat it. I bought a three-pack and donated two of them to a local animal shelter
By Gorgie
July 21, 2015
Felisyl Immune System Support Soft Chews)
This is an easy and tasty way to give L-lysine for all cats and especially FIV+ cats.
By puzzled1
new york city
September 11, 2014
he won't eat them...
even if I break them up into tiny pieces. They're not soft enough for my old guy. I found another brand that are softer and he'll eat those.
By Jennajon
February 6, 2014
Great and the cat loves them!
Used as therapy treatment for my Tuxedo who was exposed to Feline Herpes as a kitten.

Works wonderfully--only wish each chew was 500 mg instead of 250mg.
By Cindy
South Carolina
November 1, 2013
Most Economical
My vet had quoted me an outrageous price for Lysine when my cats came down with a herpes virus. This product keeps them symptom free at a fraction of the cost!
By Ely
March 19, 2013
My cats love it
I have two cats with herpes of the eye and both are happy to take 1 tab each am and pm.
By RaIrCo24
December 6, 2012
Helped my cat a lot!
My cat had sores from her feline herpes and Felisyl helped a lot to let them heal and go away. Glad I purchased this.
By Carol
Ft Lauderdale Fl
May 30, 2012
GREAT discovery
The cats don't know there's medicine in the chews, they think its a treat! They eat them up fast. I try and hide an Anixtane tablet in between 2 of the chews. Someone should make a pill pocket out of the soft chews.
By Rob
Drexel Hill, PA
February 23, 2012
Felisyl Immune Support Soft Chews
I recently purchased 3 packs of the Felisyl Immune System Support upon the reccomendation of my vet. Allof my 5 cats enjoy them and come running when I open the bag. It's still too early to determine the full effect, but I'm planning to keep feeding this product as a part of their daily diet.

By Joan
January 2, 2012
Felisyl L-lysine
I have used L-lysine for my cats with eye issues for about 2 years. I recently found this product and use is regularly as it keep their eyes clear and helps with irritation from herpes virus. This product is soft so was helpful for my friend who has an elderly cat who does not tolerate the hard treats. He also has had success with this product. I strongly recommend!
By Mar
December 1, 2011
Review for 3-PACK Felisyl Immune System Support (180 Soft Chews)
I am giving the Felisyl lysine to 2 of my cats. They are not crazy about the treats but will eat them & that is all I ask. Too early to tell if lysine is helping the herpes.

Questions and Answers

There are no questions or answers for this item.

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