• Fera Pets Lysine Immune powder jar for cats, shown with the included scoop
  • Infographic listing Fera's Lysine Immune benefits for cats: immune and respiratory health, gut health, eye health, and antioxidant support
  • Graphic detailing what's inside Fera's Lysine Immune, including 500 mg L-lysine and a clinically studied postbiotic, with no fillers, grains, or artificial ingredients
  • Chart comparing Fera's Lysine Immune to a leading competitor on lysine plus additional active ingredients and fillers
  • Supplement facts panel for Fera's Lysine Immune listing L-lysine, EpiCor postbiotic, olive leaf extract, and lactoferrin per scoop, with NASC, GMP, and Made in USA seals
  • Back label of the Fera Lysine Immune jar showing feeding directions and safety warnings
  • Back label of the Fera Lysine Immune jar showing the full ingredient list and drug interaction cautions

For Cats

L-Lysine Immune Support for Cats

4.4 out of 5.0 stars

63 Reviews

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Boost your cat’s immunity the natural way with Fera’s Feline Immune Support, blending traditional botanicals and science-backed ingredients to:

  • Promotes immune and respiratory health
  • Helps maintain normal eye function and health
  • Provides antioxidants to help maintain a normal inflammatory response
  • Supports gut health and natural immune defenses

Pairs well with:

We believe that a balanced approach is best, so we used both Eastern and Western Ingredients in formulating Fera’s Feline Immune Support. Traditional botanicals like Olive Leaf Extract and Echinacea deliver natural antioxidants to support immune health, while scientifically backed compounds like Lactoferrin, Quercetin and Lysine work to support cellular defenses.

Details for L-Lysine Immune Support for Cats

Active Ingredients

L-Lysine, 500mg

EpiCor® Postbiotic, 50mg

Olive Leaf Extract, 50mg

Organic Echinacea, 25mg

Lactoferrin, 20mg

Quercetin, 15mg

Inactive Ingredients

Chicken Liver Powder

Our Lysine Immune includes EpiCor® Pets, a powerful postbiotic that helps balance your cat’s microbiome for a strong, healthy immune system. This human-grade ingredient is packed with bioactive compounds that naturally support immune function without overstimulating it, providing a balanced response. EpiCor® also offers antioxidant power to reduce oxidative stress and supports digestive health by maintaining healthy microbial populations and digestive tissue integrity. With EpiCor® in the mix, your cat gets comprehensive support for overall wellness from head to tail.

Why Fera? for L-Lysine Immune Support for Cats

Feed orally with the included scoop. Use regularly on a long-term basis for best results.

Directions for L-Lysine Immune Support for Cats

  • Vet Created

  • 3rd Party Tested

  • Eastern & Western

  • Sustainable

  • Transparent

  • Vet Created

  • 3rd Party Tested

  • Eastern & Western

  • Sustainable

  • Transparent

  • Vet Created

  • 3rd Party Tested

  • Eastern & Western

  • Sustainable

  • Transparent

  • Vet Created

  • 3rd Party Tested

  • Eastern & Western

  • Sustainable

  • Transparent

  • Vet Created

  • 3rd Party Tested

  • Eastern & Western

  • Sustainable

  • Transparent

Pure Care, Pure Ingredients
For your pet

Frequently Asked Questions

- Lysine: Promotes immune and eye health
- Olive Leaf Extract: Contains 20% oleuropein, a polyphenol known for its potent antioxidant activity
- Echinacea: Helps support normal respiratory and immune health
- Lactoferrin: Helps enhance specific and non-specific immune function
- EpiCor Pets: Supports gut health and natural immune defenses
- Quercetin: Helps maintain normal histamine levels

Chicken Liver Powder

60 servings

This product is suitable for cats of all ages. For kittens, we recommend starting with ½ scoop and gradually increasing to the full serving size.

Our Lysine Immune Support for Cats is manufactured in the USA with domestic and imported ingredients in an FDA-registered GMP facility, and NASC certified. Each batch is third party tested for potency and purity.

Yes, these products can be taken together! If your cat is already taking our Probiotics + Prebiotics, we recommend starting out with half of the recommended serving of Lysine Immune for about a week before increasing to a full dose.

We would recommend stopping 5-7 days prior to anesthesia.

4.4
Rated 4.4 out of 5 stars
Based on 63 reviews
89%would recommend this product
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63 reviews
  • Patricia Z.
    Verified Buyer
    I recommend this product
    Pet Type? Cat
    Pet's Age? Adult
    Rated 5 out of 5 stars
    8 months ago
    Nudie’s Fav

    My Sphynx has feline herpes and this supplement helps so much with her upper respiratory system.

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  • E H.
    Verified Buyer
    I recommend this product
    Pet Type? Cat
    Pet's Age? Adult
    Rated 4 out of 5 stars
    8 months ago
    Shinier coat more vitality

    I started giving this supplement to my maine coon who had a compromisex immune system. He started showing more energy and better sleep. It is touch and go. He has a bad.eye. But I believe it is helping him success is not guaranteed and one day I am seeing small improvements. I have hope when I am using this product. We mix in his wet food ievery morning.

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  • Catherine
    Verified Buyer
    I recommend this product
    Pet Type? Cat
    Pet's Age? Adult
    Rated 5 out of 5 stars
    1 year ago
    no more allergies or vet visits!!

    I have tried Lysine, goats milk, raw food...nothing was helping my cat is allergies.

    This stuff has been a life saver!! I'm SO THANKFUL!! and I love that it's truly all natural.

    I will say she snubbed it until I really hid it in tuna flavored food. But now she has adapted

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  • Diane S.
    Verified Buyer
    I recommend this product
    Pet Type? Cat
    Pet's Age? Adult
    Rated 5 out of 5 stars
    1 year ago
    They seem to like it!

    Havent had it long enough to see health improvement but them liking it is a definite plus!!!!!

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  • Heather
    I recommend this product
    Pet Type? Cat
    Pet's Age? Adult
    Rated 5 out of 5 stars
    1 year ago
    Life-saver for my picky kitty!

    I was skeptical at first because my cat turns her nose up at everything, but this lysine immune supplements have been a game-changer. Not only does she actually eat it on her food, but I’ve noticed a big improvement in her sneezing and overall energy. It's such a relief to find something that supports her immune system and passes her high standards. Highly recommend for fellow cat parents with fussy furballs!

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Disclaimer: Customer reviews are provided for informational purposes only and reflect individual experiences. Results may vary from pet to pet.