Vetoquinol Viralys Powder Immune Supplement for Cats, 3.5-oz

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About This Item

Details

  • A highly palatable L-Lysine HCI Nutritional oral powder for cats that may be sprinkled over dry food or mixed with a small amount of canned food.
  • For cats and kittens as a nutritional supplement for conditions responsive to Lysine such as upper respiratory problems or feline herpes.
  • This powder will also help reduce inflammation of the eyes, conjunctivitis (eye discharge), squinting sneezing, sinus congestion, and so much more.
  • This L-Lysine supplement is specifically developed for cats and kittens and contains naturally occurring amino acids.
  • Manufactured according to rigorous pharmaceutical standards, L-Lysine powder can be safely administered with no known side effects for as long as required.

Ingredient Information

Instructions

FAQ

Learn More About Vetoquinol From Our Team of Experts

Related to This Item

Vetoquinol Viralys

Viralys L-Lysine Supplement for Cats

Support your cat’s immune system with Viralys L-lysine supplement! The key ingredient, lysine, supports normal eye health, respiratory health, and helps your cat maintain a strong immune system

Viralys can help cats manage conditions responsive to lysine, including:

• Squinting, watery, red, and/or itchy eyes

• Sneezing

• Runny nose

• Congestion

For Cats and Kittens          

Viralys can be given to cats and kittens of any age to support a healthy immune system.

Maintain Eye Health Support

L-lysine helps support normal eye function and health in cats and kittens.

Respiratory Health

Viralys is formulated to support respiratory health in cats and kittens.

Easy to Give

Even picky cats love the tasty maple-flavored oral gel or fish and poultry-flavored powder!

Satisfaction Guarantee

The makers of Vetoquinol are so sure your pet will like their products that they come with a 100% satisfaction guarantee.

Also Try Enisyl-F!

From Vetoquinol, Enisyl-F L-lysine supplement helps support immune health in cats and kittens of all ages.

Cats love the tasty chicken liver flavor of the easy-to-give bites or the tuna-flavored oral paste - giving you more options for high-quality immune support.

About Vetoquinol

Vetoquinol believes that a healthy pet is a happy pet. That’s why they are committed to creating uniquely formulated products that are easy to administer and designed to foster good health at every life stage. Since 1933, this independent family business has been on a mission dedicated exclusively to animal health. Their goal every day is to enrich the lives of pet parents by helping their pets be well and thrive!

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Flavor           
Seafood & Fish, Poultry
Molasses
Chicken
Chicken
Beef
—
Chicken, Liver, Meat, Poultry
—
—
Chicken, Cheese
Liver
Bacon, Meat
Packaging Type           
Tub
—
Tub
Tub
Tub
—
—
—
—
—
—
—
NASC Certified           
Yes
Yes
—
Yes
Yes
Yes
Yes
Yes
—
Yes
—
—
Sourced From           
—
—
—
United States
—
—
—
United States
—
United States
—
—
Ingredients           

Frequently bought together

Questions & Answers

32 Customer Questions

I only feed the neighborhood cats once daily, so can I double the dosage to do this?

Is there any difference between L-Lysine and L-Lysine HCL. We have been giving our cat L-Lysince, but I see that Chewy only has L-Lysine HCL.

Answer by Chewy • Jul 29, 2018
The HCl denotes that the lysine is present as the hydrochloride salt. Salts changes the properties of the lysine, making it more soluble.

Towards the end of the Viralys, there is tan/brown powder. Is this safe to use or should I throw it out?

Answer by Chewy • Aug 31, 2021
The tan or brown powder is flavoring. It tends to fall to the bottom of the tub over time. It's recommended to shake the tub before every use to keep it mixed.

What are the actual (beneficial) differences between Enisyl-F paste and Viralys gel or powder? I can't find dosing info for all 3 items to compare. Do they all provide 250 mg of Lysine HCL per serving?

Answer by Chewy • Jan 23, 2019
Enisyl-F Pump - 1ml contains 250mg. Viralys Gel - 1.25ml contains 250mg, Viralys Powder contains 500mg per scoop (0.52 grams). The lysine in either product is the same quality.
Reviews
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4.7
Rated 4.7 out of 5 stars
1678 Ratings
Terms & Conditions

Customers Mention

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

Effectiveness

93% Positive

Form and Administration

89% Positive

Ingredients

92% Positive

Nutritional Value

91% Positive

905 Customer Reviews

Rated 5 out of 5 stars
By Diane on Oct 4, 2025

Immune support powder

My almost 4 year old kitty has asthma and allergies. I put it on wet food daily. It has helped his congestion and stuffy nose. All my other four cats get dose daily

My almost 4 year old kitty has asthma and allergies. I put it on wet food daily. It has helped his congestion and stuffy nose. All my other four cats get dose daily. Their coats are silky soft. My oldest cat has eye crusty in left eye all the time. After using this product for a few days condition is gone. Recommend it.

Rated 1 out of 5 stars
By Joanna on Aug 21, 2025

No improvement :(

I've had the powder for a couple weeks now and have been giving it to my kitties 2x a day with the proper dosage, but I've seen no change. I'm disappointed since

I've had the powder for a couple weeks now and have been giving it to my kitties 2x a day with the proper dosage, but I've seen no change. I'm disappointed since this had such great reviews! Today I came home and my kitty who suffers most from eye inflammation - the main reason i got this powder in the first place, because he gets eye irritations and then rubs it so hard i have to put a cone on to stop him from hurting himself - had an inflamed eye again, and I've also still been hearing occasional coughing from my other kitties - and actually they hadn't been coughing hardly ever or had never done so before UNTIL I started giving this powder. So. Safe to say I won't be getting this again unless it magically starts working in the future, I'm not sure what to do with this giant container in the meantime haha but I'll keep trying it I suppose.

Rated 5 out of 5 stars
By Ruby on Sep 26, 2025

I got the gel.

My baby had an awful cold. Snot coming out of his nose,sneezing and coughing. It was so bad I almost took him to the emergency hospital. I ordered the gel and he

My baby had an awful cold. Snot coming out of his nose,sneezing and coughing. It was so bad I almost took him to the emergency hospital. I ordered the gel and he is much better after four days. I mix it in with his wet food. Next I will order the powder.

Rated 5 out of 5 stars
By Rose on Aug 23, 2025

Palatable and easy-to-use supplement!

My cat uses this supplement to help with his FVH-1, which causes runny eyes and nose and some minor upper respiratory symptoms. Since starting this supplement and

My cat uses this supplement to help with his FVH-1, which causes runny eyes and nose and some minor upper respiratory symptoms. Since starting this supplement and giving it on a regular basis since last year, I have seen a reduction in his symptoms. He doesn't mind the flavour at all, and it mixes in very well with his wet food, or makes a good slurry with a couple mLs of water. I like that I can get it through Chewy as well!

Rated 5 out of 5 stars
By Clyde on Sep 10, 2025

Great Product Highly Recommend

My cat got sick with a Virus (cold) and the Vet told me to try this product. I received it next day and started her on it. Three days later my cat was feeling

My cat got sick with a Virus (cold) and the Vet told me to try this product. I received it next day and started her on it. Three days later my cat was feeling great and the cold was gone. She's 8 yrs old and acting like she's 2 it works great and she thinks its a treat. Its pricey but well worth it.

Rated 5 out of 5 stars
By Andrea on Sep 9, 2025

Vet gave it me for all 3 of my kitties

I paid 60 bucks for this stuff through my vet. For all of my cats to share, i'm finally out and needed to restock up so I figured why not save it, especially is

I paid 60 bucks for this stuff through my vet. For all of my cats to share, i'm finally out and needed to restock up so I figured why not save it, especially is great for my twenty three year old kitty who has a few respiratory issues, seems to definitely lessen her symptoms.

Rated 4 out of 5 stars
By Angela on Jul 28, 2025

Boosts Immune System

I add this to my cats at least once a day (instructions say a scoop twice a day but I can’t afford that frequently at this time). One of my cats especially has a

I add this to my cats at least once a day (instructions say a scoop twice a day but I can’t afford that frequently at this time). One of my cats especially has a recurring cat herpes that always messes with her eyes and nose. This seems to be helping clear her up! I also have another cat who suffers from a chronic case of the calicivirus and since taking this he hasn’t had any tongue ulcers.

Rated 5 out of 5 stars
By Christine on Sep 10, 2025

Life changing

My cat has struggled with allergies and upper respiratory issues.Her entire life. My vet recommended this product and I have to tell you.It was life changing for

My cat has struggled with allergies and upper respiratory issues.Her entire life. My vet recommended this product and I have to tell you.It was life changing for her. I just mix it in with some treats and she eats it right up.

Rated 3 out of 5 stars
By MaxinesMom on Jul 7, 2025

You need a PhD to determine dosage

First off, the jury is still out on effectiveness as it’s only been a few days. My feedback so far is that the dosage instructions were not helpful at all! It said

First off, the jury is still out on effectiveness as it’s only been a few days. My feedback so far is that the dosage instructions were not helpful at all! It said “one rounded scoop” but did not provide a scoop to use. It then said 500mg, but no context on how big or small a corresponding scoop might be. So my friend google helped(?) me figure out that it was probably close to 1/16 a teaspoon. Which my measuring spoons didn’t include! But I did have one called a DASH, which when eyeballed appears to be about half of my 1/8 spoon. I just hope my estimations are accurate and I’m not over-medicating my cat!

Rated 5 out of 5 stars
By Robert on Jul 21, 2025

Works great

I'm using this on 2 cats to help control issues related to feline herpes. With both cats I sprinkle the powder on some wet food and mix it in and neither cat seems

I'm using this on 2 cats to help control issues related to feline herpes. With both cats I sprinkle the powder on some wet food and mix it in and neither cat seems to mind. As for function it seems to be working great neither cat is showing any signs of respiratory issues and it has cleared up both of their goopy eyes. Only complaint is the smell it is an overwhelming fish smell but it's a small thing to deal with