L-Lysine Gel for Cats (5oz) – Supports Immune, Respiratory, and Eye Health. Eases Sneezing, Runny Nose, and Watery Eyes. Tasty Salmon Flavor – Made in The USA
$18.99
Price: $18.99
(as of Oct 17, 2025 12:05:37 UTC – Details)
From the brand
Felisyl L-lysine Immune System Support Gel is a product designed to support the immune system of cats. L-lysine is an essential amino acid that plays a crucial role in various biological functions, including immune system function.
L-lysine is known to inhibit the replication of the feline herpesvirus, which is a common viral infection in cats that can cause respiratory and eye symptoms.
Immune System Support for Cats
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The seal is an indicator that the product was made by a reputable company that is committed to transparency & ethical practices.
Immune System Support for Cats
Product Dimensions : 8 x 3 x 2 inches; 5 ounces
Item model number : FEL6547
Date First Available : December 15, 2013
Manufacturer : Pet Health Solutions / HealthyPets, Inc.
ASIN : B00MO9SHBE
Best Sellers Rank: #1,555 in Pet Supplies (See Top 100 in Pet Supplies) #5 in Cat Supplements & Vitamins
Customer Reviews: 4.4 4.4 out of 5 stars 1,447 ratings var dpAcrHasRegisteredArcLinkClickAction; P.when(‘A’, ‘ready’).execute(function(A) { if (dpAcrHasRegisteredArcLinkClickAction !== true) { dpAcrHasRegisteredArcLinkClickAction = true; A.declarative( ‘acrLink-click-metrics’, ‘click’, { “allowLinkDefault”: true }, function (event) { if (window.ue) { ue.count(“acrLinkClickCount”, (ue.count(“acrLinkClickCount”) || 0) + 1); } } ); } }); P.when(‘A’, ‘cf’).execute(function(A) { A.declarative(‘acrStarsLink-click-metrics’, ‘click’, { “allowLinkDefault” : true }, function(event){ if(window.ue) { ue.count(“acrStarsLinkWithPopoverClickCount”, (ue.count(“acrStarsLinkWithPopoverClickCount”) || 0) + 1); } }); });
Immune System Support – Packed with L-Lysine (an essential amino acid) to bolster your cat’s immune defenses. A stronger immune system helps keep your kitty healthier and more resistant to common feline illnesses, giving them the best chance at a long, happy life.
Respiratory & Eye Health – Formulated to support clear breathing and overall wellness in cats. Felisyl’s immune-boosting action helps ease sneezing, runny nose, and watery eyes associated with common respiratory issues, so your cat can breathe easy and stay comfortable every day.
Tasty, Easy-to-Give Gel – Highly palatable salmon-flavored gel that cats love, making supplement time feel like a treat. No more struggles with pills – simply place the gel on your cat’s paw or nose and they’ll lick it off willingly, ensuring stress-free daily dosing.
Vet-Formulated & Trusted – Developed by veterinarians for optimal feline health benefits. Felisyl is also vet-recommended, trusted by vets for its proven benefits and positive impact on cats’ lives. Pet parents can feel confident knowing this immune support gel is backed by experts and real results.
NASC Certified Quality, Made in USA – Manufactured to the highest quality and safety standards set by the National Animal Supplement Council. Felisyl carries the NASC Quality Seal and is proudly made in the USA, so you can trust you’re giving your cat a safe, premium-grade supplement for their well-being.
Customers say
Customers find the L-Lysine gel effective at boosting their cats’ immune system and helping with sneezing and runny eyes and nose, while appreciating its tasty salmon flavor and easy-to-administer gel form. The product receives mixed feedback regarding value for money, with some finding it great for the price while others consider it not worth the cost. Customers disagree on their cats’ acceptance of the product, with some reporting their cats love it while others say their cats refuse to eat it.
8 reviews for L-Lysine Gel for Cats (5oz) – Supports Immune, Respiratory, and Eye Health. Eases Sneezing, Runny Nose, and Watery Eyes. Tasty Salmon Flavor – Made in The USA
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$18.99
Amazon Customer –
Is now a staple in my home
My cat was getting dark discharge (eye boogies) from his eye. Brought him to the vet. No infection but there were several tests they could have done to see if it was something more. It would have cost me hundreds of dollars. One test alone was close to $400. The vet recommended me to use this product first. I’m so grateful for that bc it worked! I was skeptical if my cat would like the salmon flavor, it’s the only flavor it comes in, & he loves it!! He looks forward to it every morning. He knows where I keep it & knows what the tube looks like. Once I show it to him his eyes widen, ears up & he sits straight up for it. Loves it & it works!!!!!!
HarleenQuinzelXIII –
Worth it!
My cat loves the taste of this gel! Its smell is very mild and subtly fishy. In just a week, it’s helped her runny nose & eyes clear up and she doesn’t sound nearly as wheezy. Very effective and good price for how many servings you get (about 60 for an adult cat).
Taylor –
highly recommend for FHV positive cats!
if you have a cat with FHV and flare up symptoms, TRY THIS! my cat has FHV and she doesnât flare up often, but started having a runny nose and eye, sneezing, and a little bit of a loss of appetite and lethargy. i have never tried giving her L-Lysine but wanted to implement it since sheâs getting older. within one time of her taking this her symptoms improved. day two, her eye already is cleared up and very minimal sneezing. the second day i did have to mix it with Churu treat to get her to take it, she wasnât as willing, but i donât see myself having any issues again with the help of a treat. i highly recommend. she is herself again already
LMJStar –
Cat like is and it helps
My cat is an older man and started getting upper respiratory infections earlier this year. After a few vet treatments to get rid of the URI his vet recommended we add a lysine supplement to support his respiratory system. This has been great for my cat for the most part as his nose and eyes stay clear and his congestion stays away for months. He enjoys the taste and I can just put it in his dish in the morning and he licks it right up. Overall I will keep buying it as long as my cat will take it.
Tanner Madarang –
Worked so great and fast I’m giving it to both cats now.
Not only did she stop sneezing, her personality changed. She’s sweeter. She’s a very table so she’s always a little aggressive and grouchy. After the first dose she stopped sneezing and started coming over for cuddles more frequently!
JustMeMare –
Good stuff and working well so far.
I was using a different brand in maple flavor and my cat likes it but is getting tired of it. I ordered these in salmon flavor and he loves it. He’s a very large white cat and he always has a bloody discharge from his eyes. I received this on Saturday and I can already see a big difference. I just ordered 2 more. It says it’s a gel but it is not. It’s creamy. Could be because it sat in a hot mail truck for hours.
kim myers –
Kitty health
Cats ate/licked up this product but it didn’t seem to make any difference in their health.
Allie –
Worth buying; cat loves smell and taste, large tube size, easy to feed
My sweetie is still sneezing on my face in the mornings, but I think her issues have improved a bit. Hard to tell yet. I can tell you that she LOVES the taste and smell as she licks it right off of my finger and wants more! I love that she licks it off my finger, it’s also a nice moment for us because she won’t lick anything else off of my finger. But I ran into a problem once and might have given her a tiny bit too much and it might not have agreed with her, so I suggest starting out with a tiny bit. I think she thinks it’s a treat. That’s why I got this gel vs chewable, and the size of the tube is decent size for price so it should go a long way. It is everything that I hoped for. I think it says 1/2 tsp. Good quality.