






Buy anything from 5,000+ international stores. One checkout price. No surprise fees. Join 2M+ shoppers on Desertcart.
Desertcart purchases this item on your behalf and handles shipping, customs, and support to USA.
🐾 Keep your cat thriving with Viralys — the daily lysine boost they actually crave!
Vetoquinol Viralys Daily L-Lysine Powder is a vet-recommended, fish-flavored supplement delivering 500mg of L-Lysine per dose to support immune, eye, and respiratory health in cats and kittens. Designed for easy mixing with wet food, it helps manage feline herpes flare-ups and promotes long-term wellness, making it a trusted, cost-effective choice for proactive cat care.












































| ASIN | B000FULBT4 |
| Active Ingredients | Active ingredients: L-Lysine hydrochloride, 500mg. Inactive ingredients: Brewer’s Dried Yeast, Hydrolyzed Fish (enzymatic), Hydrolyzed Poultry Liver (enzymatic), Mixed Tocopherols (a preservative), Sodium Acid Pyrophosphate, Sodium Sulfate. Active Ingredients Active ingredients: L-Lysine hydrochloride, 500mg. Inactive ingredients: Brewer’s Dried Yeast, Hydrolyzed Fish (enzymatic), Hydrolyzed Poultry Liver (enzymatic), Mixed Tocopherols (a preservative), Sodium Acid Pyrophosphate, Sodium Sulfate. See more |
| Best Sellers Rank | #1,566 in Pet Supplies ( See Top 100 in Pet Supplies ) #2 in Cat Multivitamins |
| Brand | Vetoquinol |
| Brand Name | Vetoquinol |
| Customer Reviews | 4.6 out of 5 stars 9,538 Reviews |
| Flavor | Fish & Poultry |
| Global Trade Identification Number | 00030521041480 |
| Included Components | Vetoquinol Viralys Powder, 100gm |
| Item Form | Powder |
| Item Weight | 0.01 Ounces |
| Manufacturer | Vetoquinol |
| Manufacturer Part Number | 410633 |
| Model Number | 410633 |
| Number of Items | 1 |
| Product Benefits | Immune Support |
| Specific Uses For Product | Eyes, Sneezing |
| Target Species | Cat |
| UPC | 030521041480 884291149927 |
| Unit Count | 2.5 Ounce |
| Volume | 3.5 Fluid Ounces |
J**Y
GREAT FOR FELINE HERPES! LYSINE SUPRESSES THE AMINO ACID ARGININE, RESPONSIBLE FOR FLARE UPS!!!
I work w/ my local VSA ( voluntary services for animals). I took in a few kittens that's eyes were almost completely shut with crust & their little noses were covered in crust & mucus. A pitiful site :( . I quickly took all 4 to the vet within 24 hrs. WELL, after they said it was "Feline herpes", (an upper respiratory infection that doesn't go away but can be controlled) IT ended up costing me close to $800!! With Vet costs, testing costs, & the "Wonderfully expensive" medication they gave me for Each cat, That helped some but not much!! They had liquid meds, meds that had to be put INTO their eyes like 4xs a day, & some other antibiotics. It was awful , & seriously it didn't help much at all. It lessened it some, but they needed the meds constantly! I looked on the Internet for any info I could find & found out about LYSINE !! I really thought it was a bunch of "bull" but was willing to TRY anything! I 1st bought a paste & a gel- the cats hated it. I then bought this powder. I mixed it into wet food ( not too much or they taste it!) & they ate it! After a week I noticed all their symptoms were really improving! I had STOPPED the Vets meds as the cost was killing me & not really helping them. After a MONTH all the cats were totally better, no crusty gooey eyes, no crusty nose, sneezing, ALL GONE!! I was amazed!! I studied it more, the use of L LYSINE & it's effects. It surpresses what makes the Herpes virus flare up in the system, so taking it on a Dailey basis means you won't get the flare up & the full blown symptoms! It also works in humans as well. I kept the kittens & have given them forms of LYSINE for 2 yrs now & they have NOT had another flare up since! If I stopped it for a few months, I noticed some sneezing & gunk in their eyes in the 1st year & quickly put them back on it! With 5 cats ( I had a 3 yr old when I took these in, she caught feline herpes from them as well!) it's kinda hard to make sure each one gets 250 - 500 mg Ea. When they eat out of each others bowls! So I just put a scoop into 1 3 oz can of wet, feed them 3 cans & it works great. I tried the TREATS, most cats don't care for them, also many brands you have to give each cat like 10 treats 1-2 x a day! Woa! Or another brand the treats were huge! Only 2 a day because they were the size of a golf ball! Lol. So, the cat powdered LYSINE works good, it's flavored mixes well in food & good to start on. I had no luck putting this on DRY food, I have heard many ppl do that but my cats wouldn't eat the food & most just fell to bottom of dish/bowl. I also bought & use HUMAN grade LYSINE 500 mg tablets & crush them up w/ a spoon & mix into wet food. This is VERY cost effective! It taste stronger than this flavored powder, so use a good wet food to mix with & you wont have a problem. My cats got use to it fast. You can also buy LYSINE powder in BULK on here, it's human grade & already finely crushed up. It works GREAT & cost MUCH less. Plus I like that it's "human" grade. I now can skip months at a time with no LYSINE & they still get no flare ups. This LYSINE is a God send! I recommend this powder if starting out, it's flavored and cats will take it well. But cost wise, the pills, tablets, capsule at your store or on here ( cheaper!) are strongest & the best I've found( crush up finely) . bitter, but cats really don't "taste" bitter I've heard. Either WAY or BRAND you choose it will all but cure your cats of the virus, you won't have huge vet bills & expensive meds that are worthless. 5 cats taking LYSINE on & off for 2 yrs and they have NO MORE SYMPTOMS & are very happy healthy spoiled kitty's... So please do yourself, your wallet, & your cats a favor & put them on a LYSINE regimen of 250 mg a day OR - 500 mg 1-2 x's a day for a flare up or to start off with. Once symptoms subside, you can stay with 250 mg a day to keep them away for good! Btw, In order to replicate & cause FLARE UPS , in humans & cats the herpes virus needs "ARGININE" another amino acid such as LYSINE . when LISINE is taken at higher doses, it prevents the amino acid ARGININE from over producing & hence preventing outbreaks of the herpes virus. So just check your pets FOODS, TREATS etc for any ARGININE ( L-ARGININE ) in them as this will ADD to your problem!! There ARE foods with this in the ingredient list I've found, so just FYI to be safe. Hope this helps someone with the problems I went through & learned from along the way!! :) Jenn ~
L**H
A staple for pet lovers
I've had my car on this Lysine for years now and it truly keeps keep his feline herpes flare ups at bay. Even if he has a flare up this keeps them from getting out of control. I keep our other cat on it as well to protect her from his virus and she's free of it. I believe this really helps boost both their immune systems. Our vet originally told us about it and I was so happy to find it on here. Both our cats love the flavor and it smells just like fish - very important as cats depend heavily on their sense of smell for eating. It's super easy to mix in with their wet food and comes with a little scooper inside.
B**R
My picky cat LOVES this!
I’m not one to write reviews but this powder has been a literal godsend. I have a semi-feral 7 year old cat who’s had chronic sinus and eye infections her whole life. She will not take ANY medication and in fact goes on a hunger strike if I crush anything up to put in her food. I bought this hoping the flavor would entice her, and it is absolutely her favorite! She’s had no issues eating this mixed into her wet food and I’m noticing an amazing difference in just 4 days. She is sneezing WAY less than usual and her eye (which had started getting yucky again right before I bought this) has almost completely cleared up. Cannot recommend this enough!!
T**0
Effective and easy
We use this whenever any of our cats or foster cats/kittens show any signs of a "kitty cold". Watery eyes, sneezing, things like that. So far it has helped them recover quickly and I believe helps prevent the spread of the virus. We mix it in with a little soft food and they eat it right up.
K**R
Works great for my cat's allergy issues, but watch for expiration date
Works great for my cat, 2x a day. Mix it in with his food, no problems. He has allergy issues and without this he'd be sneezing quite a bit. Started using this year for inside cat, but had previously used, off and on, for a feral with respiratory issues. Originally bought from vet and now with subscribe and save, definitely saving some $. One note, I received in September 2025, and just opened it, noticed expiration is 2/2026, which seems a fairly short time to use up. My 1st container I had a few years before expiring, and that was 1 I'd purchased from my vet. I wasn't sure if I'd have enough to get to my October subscribe and save delivery, so ordered in September. Will not place order until I absolutely need it, and definitely keep eye on expiration dates.
K**R
Actually noticeable effect in my cats well being after feeding in her wet food. A must buy!
My cat has feline herpes respiratory virus ( she was a stray I rescued and she’s hade it since she was a kitten) I have really struggled to do what I can to help her feel better, humidifier, eye ointment from the vet, comb her often since breathing is hard with a runny nose she’s not cleaning herself so I’ve gotten her combs but I bought this stuff and I noticed a definite improvement in her HIGHLY RECOMMEND! She seemed happier and more playful. It easily dissolves in the wet catfood ( I don’t recommend for dry but I think you can put in water - I personally wouldn’t recommend dry catfood for a cat with immune issues it’s just not good quality) But this is a good price the scoops last and any thing that helps the cat feels better is worth it for me, I’m going to try it in the paste form next and I’ll update on that! ( she seems to like the taste when it’s in her wet food) If you are not combing your kitty with respiratory issues I highly recommend that as well so the cat feels better. I noticed the older she gets that’s getting harder. And don’t forget to try a humidifier and I even use a gentle fan she seems to enjoy sitting in front of both… anything that helps!
E**E
Worked like magic
Note that my cat was never diagnosed with a virus (herpes) infection. The Internet is also very inconsistent on the usefulness of lynsin treating cats with URI due to virus infection. So I was skeptical of this and it seems kind of expensive. I decided to give it try because 1) it is still cheaper then vet visit & prescription, and 2) I can get it on the same day delivery. My cat has been sneezing off and on for awhile. Last few days he started to eat less and sleeps a lot more then usual. Since he already had 2 rounds of antibiotics before but the sneezing still returned, I'm concerned with giving him more antibiotics. So I decided to try the herbal / natural remedies first. The result is nothing short of magical. After 2 doses, his sneezes have noticeable lessened, he is more alert, and eating better. After 2 days, his sneezing has stopped and he is chasing my other cat. I'm absolutely shocked of the fast recovery. All I can say is I'm glad that I gave this a try.
P**P
Saved my strays
So I feed the stray cats in my neighborhood but have never actually owned a cat so I didn’t know that they could get sick or get respiratory infections. For about a week when I went to feed them I noticed they were sneezing, wheezing while breathing, eyes just gunky and crazy looking and I had no idea what was happening so I googled their symptoms and found out they had respiratory infections. I ended up purchasing this product in hopes that it would help and oh my gosh they helped so much. After about two weeks each cat that was sick was breathing better, no more eye gunk, and no more coughing and sneezing. I still give it to them like every other day just to ensure they stay healthy but yes, if you’re on the fence just buy it! Totally worth it! Feel like it saved my cats lives to be honest. I mixed it in with soft cat food and then mixed the soft food in with their hard food and just put enough to cover all the cats so even if they weren’t sick I feel it’s still beneficial.
D**E
La lysine renforce le système immunitaire
Excellent produit.
J**G
My cats like it!
I was recommended to buy this product as my cat had watery eyes and sneezes frequently. After taking this supplement, all is well. I give it to both cats and they liked it maybe because of the chicken and fish flavour.
J**A
Works well
This is very good tonic for cats
K**Y
Excellent product
Have used product before in jel form and now am trying powder for convenience to add to can food. I think this is a very effective product/supplement. Highly recommend 👌🏻
D**N
Herpès félin
Très bon , mon chat a arrêté de éternuer après 3 jours ( herpès félin )
Trustpilot
1 day ago
2 weeks ago