Vetoquinol Enisyl-F Lysine Bites Chicken & Liver Flavored Immune Supplement for Cats

By Vetoquinol
Rated 3.6065 out of 5 stars

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$28.99Chewy Price
$27.54Autoship Price
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About This Item


  • Made in the USA.
  • Comes in a highly palatable poultry flavor, and may also be used as directed for as long as needed.
  • These small, bite-sized treats are specifically developed for cats and kittens to help treat conditions responsive to lysine such as upper respiratory problems.
  • They also work to reduce the severity and duration of symptoms caused by the feline herpes virus.
  • Routine administration of these treats can reduce herpes flare-ups as well as inflammation of the eyes, conjunctivitis, squinting, sneezing, sinus congestion and more.

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Nutritional Information

Feeding Instructions


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Frequently Bought Together

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$16.99Chewy Price

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Total Price: $67.88

Trusted Immune System Support

Adding L-lysine as a supplement to your cat's diet is an easy way to help support her long-term health. As a market leader with a wide range of L-lysine products, Vetoquinol puts this active ingredient in tasty chews and bite-size morsels, plus paste, gel and powder form so you can find the best way to offer it to your kitty. These supplements are specifically designed for felines to support the immune system, and maintain respiratory an

Seal of Quality

Out of thousands of animal supplement companies, only a hundred are audited NASC members, including Vetoquinol. That means they've undergone a comprehensive quality audit to earn the NASC Quality Seal. Displaying this seal on their products means that you can rest assured that they are committed to following the highest current standards of quality in the industry.

Enisyl-F & Viralys Products

Specially formulated Enisyl-F was the first lysine-based nutritional supplement developed for veterinary use for kitties. Supplementing with L-lysine is helpful for managing the symptoms of upper respiratory infections in kittens and cats that were strays, and those in shelters.


Veterinarian formulated to deliver just the right dose in a treat with cheese, chicken, liver and hickory smoke flavors.


Tiny mouthfuls of L-lysine disguised as a delicious snack with savory chicken fat and chicken liver.

Oral Paste

Highly palatable paste that can be given by mouth, mixed with food, or even applied to paws for your cat to lick off.

Oral Powder

Delivers L-lysine HCl in a powder with fish and poultry liver flavors that cats crave—just sprinkle it on top of food.

Oral Gel

Cats only need a small amount of this extremely palatable gel to get the benefits of L-lysine HCl.

About Vetoquinol

Vetoquinol is a family-owned company devoted exclusively to finding innovative solutions for animal health issues. They've shown more than 80 years of dedication, researching everything from oral hygiene to urinary and kidney health to create products that are effective and safe for the pets you love and care about. Founded in 1933 with an expertise in pet pain management and veterinary resources, Vetoquinol has gained the continued trust of pet parents and vets worldwide.
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Top IngredientsArabic Gum, Brewers Yeast, Calcium Propionate...Active Ingredients: L-Lysine, N, N-Dimethylglycine HCl (D mg)....Active Ingredient: L-lysine., Inactive Ingredients: Artificial Sweetener, Citric Acid...Dried Brewers Yeast (grain & soy free); Catnip (Leaf); Chicken Liver (hydrolysate); Fish Oil (Salmon); L-Lysine Mono HCl; Mixed Tocopherols or Natural Tocopherols (Natural Preservative); Quercetin Dihydrate; Rosemary Leaf Extract....l-lysine, natural chicken liver flavor, oat flour...
LifestageKitten, Adult, SeniorKitten, Adult, SeniorKitten, Adult, SeniorKitten, Adult, SeniorKitten, Adult, Senior
Health FeatureEye Care, Immune Support, Respiratory CareImmune SupportEye Care, Immune Support, Respiratory CareEye Care, Immune Support, Respiratory Care, Allergy ReliefImmune Support
Food FlavorPoultry, Meat, Chicken, LiverPoultry, Meat, Chicken, LiverSalmonChicken, TunaFruits & Vegetables, Chicken
Food FormTreats, SupplementSupplementSupplementPowderSupplement
Special DietNo Corn No Wheat No Soy, Non-GMO, Natural

Questions & Answers

7 Customer Questions

How many chews are there per bag?
Answer by ChewyJan 24, 2018
As this bag is measured by weight, there is no approximate number per bag.

Can the bites and the powder be used together? We've begun feeding wet food only once a day for weight management and our herpes-positive cat is now only getting one dose of Lysine.
Answer by ChewyJun 12, 2018
Before combining any supplements, vitamins, or medications, it's always recommended to consult your vet for the healthiest and most accurate use.

how big are the bites?
Answer by ChewyJan 09, 2019
The treats are approximately the size of a green pea.

What is the calorie content?
Answer by ChewyAug 07, 2023
There is approximately 7 calorie per chew.

ReviewsWrite a Review

Rated 3.6065 out of 5 stars
338 Ratings
Would recommend to a friend

337 Customer Reviews

Rated 5 out of 5 stars
By KATHRYN on Oct 29, 2023

Great for my cat with just 5 bits every other day

My vet prescribed these for my older cat with feline herpes virus. I only give her like a ktten portion of 6 bits every other day and they seem to be helping quite a bit. Nice that I can get them from Chewy instead of a visit to the vet.

Rated 1 out of 5 stars
By Deborah on Oct 7, 2023

Hard Treats

I ordered these lysine treats for my cat and found that they are TOO HARD to bite. I tried them on my other cats and NOT ONE CAT would eat them. I tried to break them up but they are too hard for me to even break. Terrible purchase, complete waste of money.

Rated 5 out of 5 stars
By Kathryn on Oct 21, 2023

My cat thinks they're treats!

My vet recommended these for my cat, and she loves them! She doesn't have teeth, but she is able to eat these bite-sized yummies and loves it when she hears me open the packet. She really does think they're treats!

Rated 5 out of 5 stars
By LR on Oct 30, 2023

This was recommended by our vet. It just didn’t work out for us. Kitten didn’t like the flavor and would not eat it. There was nothing wrong with the product, we just have a fussy cat.

Rated 5 out of 5 stars
By Gracie on Nov 29, 2023

Lysine bites

Our cat is susceptible to respiratory problems, but since she has been taking this supplement, she has had no problems,

Rated 5 out of 5 stars
By Shirley on Nov 2, 2023


My cat just loves these treats. Not only are they good for her but the taste is great. She looks forward to them everyday.

Rated 2 out of 5 stars
By Ange on Sep 17, 2023

Way to hard

Great amounts of ingredients however they are supposed to be chewy not as hard as pebble rocks. My cats neither one will chew these. They get them in mouth and then spit out...

Rated 5 out of 5 stars
By Gabriela on Nov 1, 2023

Kitten Loves These

These are the only lysine treats that my kitten will eat! They are not for everyone as they are hard.

Rated 4 out of 5 stars
By jo on Jul 26, 2023

My vet reccomended this product for my kitty. they are super hard my boy has very few teeth and it was super hard for him to eat them without soaking them overnight. I tired to mix them into his food he would just pick around them even after they had been soaked. I think it just wasnt the right product for us.

Rated 5 out of 5 stars
By mrMlysine on Sep 2, 2023

pinky cat loves em

I have a cat I have been having trouble medication for FH and asthma But this form of lysine she was crazy for Had to reach up a button after, but not the bites