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Felisyl L-lysine Gel for Cats (5 oz)

Item: FEL6547
Compare to: $14.99
You Save: $3.50!(23%)

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


This veterinarian formulated L-Lysine gel is recommended to help the immune system with amino acid support in a salmon flavor cats love. Felisyl® also helps support respiratory health and maintain normal eye function and health. With 500 mg of L-Lysine per ½ teaspoon.

For Use In: Cats


Guaranteed Analysis per teaspoon (6G):
All quantities are minimum unless stated otherwise.
Crude Protein 4.52%
Crude Protein (max.) <0.75%
Crude Fat 19.54%
Moisture (max.) 74.27%

Calorie Content (calculated): 2,000 kcal/kg (12 kcal/teaspoon)

Ingredients: Water, L-Lysine Monohydrochloride, Stearic Acid, Soybean Oil, Cetyl Alcohol, Lecithin, Salmon flavor, Methylparaben (Preservative), Potassium Sorbate (Preservative), Sodium Benzoate (Preservative), Carboxymethylcellulose, Ascorbic Acid, Xantham Gum.

Useful Information

Feeding Directions

Administer orally. Place a small amount on cat's nose to stimulate taste interest. Once interest has been established, a syringe or teaspoon may be used. Can also apply gel directly on cat's paw and allow cat to lick off.

  • For Kittens under 6 months of age: ¼ teaspoon twice daily
  • For Cats 6 months or older: ½ teaspoon twice daily
  • Or use as directed by your veterinarian

Allow 3-4 weeks for best results. This product is intended for intermittent or supplemental feeding only. Individual results may vary. For animal use only. Do not use if product appears to be tampered with or seal is broken.

Storage: Store product in cool, dry place. Avoid temperatures above 86° F.

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

There are no questions or answers for this item.

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