Felisyl L-lysine Gel for Cats (5 oz)

Item: FEL6547
Compare to: $14.99
You Save: $3.50!(23%)
This item has been discontinued.

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 gel 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 cat'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 gel helps keep your cat healthy by supporting the immune system naturally so that it can function normally and produce antibodies. Felisyl L-Lysine Gel 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 maple flavored gel that your cat will enjoy eating, making it easy to administer on food or right on the cat's paw.

For Use In: Cats

    Key Features:
  • L-lysine 250mg per ¼ teaspoon
  • Palatable Gel
  • For cats with FHV-1 Feline (Feline herpes virus)


Guaranteed Analysis (per ¼ teaspoon):
L-lysine 250 mg

Inactive Ingredients: Artificial Sweetener, Citric Acid, Maple Flavor, Purified Water, Potassium Sorbate, Riboflavin 5'-Phosphate Sodium, Sodium Benzoate and Sodium Carboxymethylcellulose.

Useful Information

    Instructions For Use:
  • Cats over 6 montsh of age: ¼ teaspoon twice a day.
  • Kittens under 6 months of age: ⅛ teaspoon twice a day.
  • Adjust dosage according to veterinarian's recommendations.

CAUTIONS: An examination from a veterinarian is recommended prior to using this product.

WARNINGS: For animal Use Only

Keep Out Of Reach Of Children and Pets

Store At Controlled Room Temperature

Customer Reviews

7 Reviews
57% (4)
14% (1)
0% (0)
0% (0)
29% (2)
71% Recommend this product (5 of 7 responses)
Santa Fe, NM
September 21, 2017
Excellent for cats with FIV
A dime-sized serving of this gel twice a day helps keep my FIV+ cats healthy. In particular, it seems effective at keeping their otherwise-frequent eye infections at bay. I highly recommend this product.
By Maiko95
April 22, 2017
Great product for a good price
I switched to this brand because of the price and it works just as well as the other brand and doesn't seem to smell as bad either
By Katlady
April 10, 2015
Never Again ! ! ! !
I was using Viralys gel for my cat. Decided to try Felisyl because the ingredients are the same and it's much cheaper. BIG MISTAKE!!! I had no problem getting her to swallow Viralys, but she spits out the Felisyl. It must taste awful. It is much darker in color and very runny. I then have to wash her and myself. The Viralys is more of a gel and easier to manage. I will definitely go back to Viralys. I wish Viralys would be sold at a more compatible price. I really can't tell that either lysine brand is really helping her with her sinus problems due to the herpes virus.
By Pat
March 20, 2015
Better than chews
My cat rejected chews, even crumbled in her food. I tried them, they are bitter. The gel is sweet and she liked it okay. She would eat her food with it mixed in most of the time. But she was a little reluctant and looked questioningly at me. Powder, however, worked great for her. But I think the gel will work for most cats all the time.
By Kat
March 7, 2015
Better value than Viralys for the exact same thing!
By Willie J
May 12, 2014
Tastes Horrible
6 cats and not one nibble. Will go back to Viralys gel.
By bgfuqua
February 24, 2014
Seems to be as good as vet brand
Seems to work as well as vet's brand at lower cost.Easy to mix with food.

Questions and Answers

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