Felisyl L-Lysine Gel Salmon Flavored Immune System Support Healthy Tissue, Respiratory, & Vision Supplement for Cats, 5-oz tube

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At a Glance

  • Immune Support
  • Eye Care
  • All Lifestages
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About This Item

Details

  • Powered by L-lysine, an essential amino acid that promotes healthy antibody levels, this supplement is ideal for cats prone to FHV-1 flare-ups, seasonal stress, or general immune challenges.
  • It helps ease sneezing, runny nose, congestion, and watery eyes associated with common upper respiratory issues, perfect for cats in need of gentle respiratory support or allergy relief.
  • Great for picky eaters and kittens, the smooth, salmon-flavored gel is easy to place on your cat’s paw, nose, or dish for fuss-free daily dosing.
  • Vet-formulated and recommended to deliver targeted immune, respiratory, and eye health support, this L-lysine gel is safe for daily use in kittens, adults, and senior cats.
  • Made in the USA and manufactured under rigorous quality and safety standards, this high-quality supplement offers consistency and peace of mind with every dose.

Ingredient Information

Instructions

FAQ

Learn More About Felisyl From Our Team of Experts

Felisyl L-Lysine Immune System Support

Breathe easy knowing your cat's respiratory system is supported for optimal wellbeing with Felisyl. Known for its immune-boosting properties, L-lysine helps strengthen your cat's natural defense mechanisms against common illnesses and infections.

Symptom Management

L-lysine is frequently used to manage symptoms associated with feline herpesvirus type-1 (FHV-1), a common viral infection in cats. Symptoms of FHV-1 include sneezing, eye discharge, and respiratory issues.

Tasty and Convenient

Felisyl L-lysine is easy to administer. It comes in granules, gel, and tasty soft chew form, making it hassle-free to incorporate into your cat’s daily routine. Your kitty will enjoy the delicious taste, too!

Supports Eye and Respiratory Health

Felisyl L-lysine can help reduce the severity, duration, and frequency of flare-ups of respiratory symptoms associated with viral infections, such as sneezing, coughing, and congestion.

About Pet Health Solutions

Pet Health Solutions is built on a philosophy of holistic pet care and wellbeing. With veterinarians on staff, their optimized formulations of supplements, topical, and dental products meet strict NASC (National Animal Supplement Council) standards.

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Questions & Answers

2 Customer Questions

How many servings per tube?

Answer by Chewy • May 01, 2025
The total content of the Felisyl-Gel tube is 142 grams, which equals approximately 25 teaspoons. Each dose is a portion of a teaspoon. For Kittens under 6 months of age, give ¼ teaspoon twice daily. For Cats 6 months or older, give ½ teaspoon twice daily.

Can this be added to wet food?

Answer by Chewy • Sep 29, 2025
The manufacturer recommends administering orally. A small amount can be placed on your cat's nose to stimulate taste interest. Once interest has been established, a syringe or teaspoon may be used. It can also be applied directly on cat's paw to allow cat to lick off.
Reviews
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4.4
Rated 4.4 out of 5 stars
451 Ratings
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Customers Mention

Chewy identifies key considerations with the help of artificial intelligence and our veterinarians.

Effectiveness

83% Positive

Form and Administration

77% Positive

Ingredients

83% Positive

Nutritional Value

83% Positive

197 Customer Reviews

Rated 5 out of 5 stars
By Teckla on Dec 23, 2025

Ernie loves the taste!

I was worried Ernie wouldn’t like this because he’s not a salmon fan but he eagerly kicks this up. I squeeze it on my finger and he licks it off. He won’t let me

I was worried Ernie wouldn’t like this because he’s not a salmon fan but he eagerly kicks this up. I squeeze it on my finger and he licks it off. He won’t let me out it on his paw nor will he touch it if I squeeze into a saucer. I’ve not seen an improvement yet with his eyes but maybe it’s too soon to tell. What I really need to do is get him to the vet to make sure there isn’t something more serious going on.

Rated 4 out of 5 stars
By Loki on Nov 30, 2025

Inconsistent thickness

It works excellently for my cat's stress-induced feline herpes as well as usually being great for coating pills for both of my cats. The consistency is unpredictable,

It works excellently for my cat's stress-induced feline herpes as well as usually being great for coating pills for both of my cats. The consistency is unpredictable, though. Sticking it in the fridge helps to firm it up, but it's not supposed to be as watery as it is sometimes. The consistency has not had an effect on how well it works, but does effect how willing my cat is to actually want to take it. When it's thicker he will lick it from an oral syringe or off of a plate like it's a treat, but when it's thin he avoids it and it tends to melt pills unless it's straight out of the refrigerator. It's not Chewy's fault, the manufacturer needs to do more quality control. It does work either way, though, and hasn't made my cat sick or anything. It helps keep his runny, itchy eyes from turning into another bout of pneumonia, so definitely worth the price. Also, the salmon flavor is much preferred over the maple one (at least with my cats). I suggest getting 3ml oral syringes that come with caps if you buy this. They make it way easier to measure, administer, and refrigerate as needed.

Rated 1 out of 5 stars
By Kym on Dec 27, 2025

7 cats walked away from it.

I have 7 indoor cats and was hoping that they would like this. They are all getting older and some have eye and Immune issues. All 7 turned up their noses and walked

I have 7 indoor cats and was hoping that they would like this. They are all getting older and some have eye and Immune issues. All 7 turned up their noses and walked away from this. Not one of them would eat it. I'm very disappointed. I feel like I just threw away 19.00. I'm not sure what is in it that they don't like. This company needs to work on the smell and taste.

Rated 4 out of 5 stars
By Jacquie on Dec 3, 2025

Cat enjoys it, wish it worked a bit better

My cat actually likes the flavor of this which is shocking as she's very picky. The consistency is very watery so it'd be easier to administer in a syringe but I

My cat actually likes the flavor of this which is shocking as she's very picky. The consistency is very watery so it'd be easier to administer in a syringe but I just goop some on my finger and wipe it in her mouth. She'd lick it up herself but she knows a treat is coming after and will snub it for that. This was for her herpes and allergy flare ups and in the past lysine knocked it out within a week. I'm going on 3 or so weeks and her flare is reduced but still there. She's also on a steroid which I think is doing the bulk of the work. Since it's easy to give her and she likes it I'll get a second tube and continue!

Rated 5 out of 5 stars
By Janice on Dec 14, 2025

Cats loved the taste

I bought this for my one kitten, Petie, because he was always sneezing and had a snotty nose. I put it on a little spoon and he licks it right off. I noticed that

I bought this for my one kitten, Petie, because he was always sneezing and had a snotty nose. I put it on a little spoon and he licks it right off. I noticed that he was sneezing less within the first few days of taking it. And just today, Petunia, started sneezing and seems congested so I gave her some too and she licked it right off the spoon. So hopefully it helps her too.

Rated 2 out of 5 stars
By Margit on Dec 25, 2025

Bombay said no thank you

Bombay has respiratory issues and I was looking for a product to strengthen his immune system. This may be it but Bombay rejects it! I couldn’t find a way yet to

Bombay has respiratory issues and I was looking for a product to strengthen his immune system. This may be it but Bombay rejects it! I couldn’t find a way yet to “sneak” it into his food because he wouldn’t eat his food then.

Rated 3 out of 5 stars
By David on Nov 1, 2025

Cat didn’t love it

I was excited to try this because I had only ever found maple-flavored lysine before, but my cat’s response was unimpressive. I was really hoping he’d like it as

I was excited to try this because I had only ever found maple-flavored lysine before, but my cat’s response was unimpressive. I was really hoping he’d like it as much as the fish-flavored hairball paste, which he and my other cat love so much they’ll lick it right out of a bowl. Unfortunately, I still have to stick this in his mouth. At least I’m pretty sure he doesn’t mind the taste, but I was really hoping I’d found another product I wouldn’t have to administer manually.

Rated 5 out of 5 stars
By Ted on Nov 21, 2025

Product was excellent - Customer Service even better

Before getting this shipment we had a problem with our password. The Customer Service rep took care of this problem with ease. She asked about my dog. I told

Before getting this shipment we had a problem with our password. The Customer Service rep took care of this problem with ease. She asked about my dog. I told her that Cali had passed away. The next day we received a bouquet of flowers. I was impressed. This is Customer Service going way beyond the extra mile.

Rated 5 out of 5 stars
By Maureen on Dec 16, 2025

Seems to be helping

My poor little kitty - flat nose causes her all sorts of issues. The Felisyl Lysine Gel seems to be helping her sniffling, running nose, and sneezing. She's

My poor little kitty - flat nose causes her all sorts of issues. The Felisyl Lysine Gel seems to be helping her sniffling, running nose, and sneezing. She's doing much less of all those since starting the Gel.

Rated 5 out of 5 stars
By Laura on Nov 14, 2025

Sneezing is gone

Something for my cat's allergies and he loves the taste. He is picky too. His sneezing has subsided since he has taken this and it happened pretty fast. He has had

Something for my cat's allergies and he loves the taste. He is picky too. His sneezing has subsided since he has taken this and it happened pretty fast. He has had a sneeze problem for over a year with snot coming out, eww. He doesnt have either, anymore, since taking this supplement.