--- product_id: 35570276 title: "Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4)" brand: "tomlyn" price: "€ 157.71" currency: EUR in_stock: true reviews_count: 13 category: "Tomlyn" url: https://www.desertcart.pt/products/35570276-tomlyn-l-lysine-immune-support-powder-for-cats-3-5 store_origin: PT region: Portugal --- # Fish-flavored for easy dosing Promotes normal eye function Supports strong immune & respiratory health Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) **Brand:** tomlyn **Price:** € 157.71 **Availability:** ✅ In Stock ## Summary > 🐾 Keep your cat thriving with every scoop—because their health deserves the best! ## Quick Answers - **What is this?** Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) by tomlyn - **How much does it cost?** € 157.71 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.pt](https://www.desertcart.pt/products/35570276-tomlyn-l-lysine-immune-support-powder-for-cats-3-5) ## Best For - tomlyn enthusiasts ## Why This Product - Trusted tomlyn brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Flavor Cats Crave:** Palatable fish flavor ensures your feline friend never skips a dose. - • **Simple Daily Routine:** One to two scoops daily easily mix into food—no fuss, just results. - • **Trusted by Thousands:** 4.6-star rating from over 5,400 cat parents who won’t compromise on care. - • **Vet-Approved Immune Boost:** Clinically formulated L-Lysine powder to fortify your cat’s natural defenses. - • **Targeted Respiratory Relief:** Helps manage sneezing, runny nose, and watery eyes for happier, healthier cats. ## Overview Tomlyn Immune Support Daily L-Lysine Supplement is a vet-quality, fish-flavored powder designed to support cats’ immune and respiratory health. Ideal for managing common feline issues like sneezing and watery eyes, it promotes normal eye function and is easy to administer by mixing into food. Trusted by thousands of cat owners, this 4-pack offers a convenient, effective daily health boost for cats and kittens. ## Description desertcart.com : Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) | Daily Fish-Flavored L-Lysine Immune Support, Cats and Kittens, Aid Eye, Respiratory, and Immune Health : Pet Supplies Review: Great stuff for feline herpes; plus, a cautionary tale and a solution to a problem - I purchased this as a replacement for another brand (Viralys) that I had been getting through my vet. One of our kitties had a "cold" when we adopted her. That "cold" just wouldn't clear up. She had a weepy eye and sneezles for weeks. When we took her to the vet, the vet said it was kitty herpes and prescribed the Viralys (at $30 a container). It's l-lysine in powder form; you sprinkle it on the cat food. There is no cure for feline herpes, but l-lysine helps clear up the symptoms. (For those who want to know how l-lysine helps, The Cat Doctor & Friends in Santa Clarita says, "We use L-Lysine to fool your cat's herpes virus into self-destructing by using L-Lysine, instead of another amino acid Arginine, when making new copies of itself. This decreases the amount of herpes virus in your cat's body and hopefully eliminates clinical signs such as sneezing or squinting one eye and reddish brown discharge. Green or yellow discharge from your cat's eye or nose is probably not feline herpes and deserves a veterinary visit.") The Viralys l-lysine powder not only worked great, clearing up the weepy eye and drippy nose within a remarkably short amount of time, it was also loved by all our kitties. (The vet said it wouldn't hurt any of them to eat it.) However, at $30 a container, and with the stupid mistake I made that wasted half a container (see below), I wanted to find a less expensive alternative. And I did. This product, the Tomlyn Scientifics l-lysine, seems to be identical to the Viralys, and costs half what my vet was charging me. My one concern was whether it would taste as good to the kitties, and it does indeed seem to. == My Stupid Mistake and How You Can Avoid It == When I first got the Viralys from my vet, I made a stupid mistake. I used the little scoop that comes with the powder to sprinkle the lysine powder on the cat food, and then I used the scoop to stir the powder into the food. Then I returned the scoop to the container. Those of you who are familiar with good sanitation practices will be able to predict what happened next: after a while, the tiny crumbs of cat food I had inadvertently transferred to the container gave birth to new life. In a few weeks, I saw suspicious little clumps and balls in the powder. I threw out the rest of the powder rather than risk making my kitties sick. After thinking about what I could do to prevent wasting my kitties' medicine (and my money), I realized the solution: put the powder into a shaker container so it never gets contaminated. After shopping around, I purchased the Kaiser Bakeware La Forme Select Sugar/Spice Shaker Set (available here on desertcart), which is just the right size for the powder. I'm using the shaker lid with the largest holes. Now all is well. Review: Only took about a day to see results - I have an aging cat and her eyes "drool" brown tears. As a former feral cat, she gets a bit snarfy when I try to wipe her eyes and then thrashes her head around, as cats will do. Now I rarely have to do that. And she sneezes much less often. (Her condition does not respond to antibiotics, so it is not bacterial in nature). I add the directed amount of L-Lysine to about one ounce of canned food twice a day and now her eyes are about 90 - 95% tear free. Only took about a day to see results, as I recall. Another of my cat family has chronic ulcers on his tongue and gums and my Vet wanted to treat him with steroids. I thought I'd try treating him with L-Lysine first, since with his disposition, steroid pills or injections would be extremely difficult to administer. And not good for him long term. To keep my other two cats from stealing the wet food with the L-Lysine, I decided to serve it to all 4 cats. Not one has given the slightest indication that he/she knows that the food has "additives" in it. I have used a wide variety of flavors of a couple of popular brands of the 6.5 sized canned food. Seems that every flavor masks the mild flavor of the L-Lysine, or could be they like the flavor! So I've been using this jar for exactly one month for 4 cats, using 4 rounded scoops twice a day as per package directions. There is still a little left. So if you are treating just one cat, I suspect this jar/container should last about 4 months. Worth the price if it helps. (I haven't had the vet check the cat's mouth yet, but he seems less unhappy. (The cat, not the Vet!) This cat is rather crabby by nature and WILL NOT let me look in his mouth, or even pick him up and I have the scars to prove it! :) However, judging by his behavior, I believe his condition has improved, but I'm fairly certain he still has some ulcers. Can't say I would recommend it for mouth ulcers, but I would recommend this for a cat with teary eyes or runny nose issues not bacterial in nature and not responding to antibiotics. ## Features - L-Lysine supplement for cats; supports normal eye function, respiratory health, strong immune system - Helps manage common feline health issues; sneezing, runny nose, squinting and watery, inflamed eyes - One to two scoops daily provides support for the immune and respiratory system for kittens and cats - Our vet-quality L-Lysine powder provides immune support for respiratory issues for as long as needed - Cats love our tasty, palatable fish-flavored powder; easy to dose and administer, simply add to food ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B01BNWB3BI | | Active Ingredients | sodium acid | | Allergen Information | Soy | | Best Sellers Rank | #22,761 in Health & Household ( See Top 100 in Health & Household ) #24 in L-Lysine Nutritional Supplements | | Brand | TOMLYN | | Brand Name | TOMLYN | | Customer Reviews | 4.6 out of 5 stars 5,457 Reviews | | Flavor | Fish | | Included Components | sodium acid | | Item Form | Powder | | Item Highlight | Daily Fish-Flavored L-Lysine Immune Support, Cats and Kittens, Aid Eye, Respiratory, and Immune Health | | Item Weight | 1.5 pounds | | Manufacturer | Tomlyn | | Manufacturer Part Number | 75403343 | | Model Number | 433343 | | Number of Items | 4 | | Product Benefits | Eye Health | | Specific Uses For Product | Active | | Target Species | Cat | | UPC | 030521033430 | | Unit Count | 4 Count | | Warranty Description | See Manufacturers Website | ## Product Details - **Active Ingredients:** sodium acid - **Brand:** TOMLYN - **Flavor:** Fish - **Item Form:** Powder - **Item Weight:** 1.5 pounds ## Images ![Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) - Image 1](https://m.media-amazon.com/images/I/61Q-EGg7UfL.jpg) ![Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) - Image 2](https://m.media-amazon.com/images/I/61+XgygpqBL.jpg) ![Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) - Image 3](https://m.media-amazon.com/images/I/6140YOjNkKL.jpg) ![Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) - Image 4](https://m.media-amazon.com/images/I/51DJl6Jg3hL.jpg) ![Tomlyn L-Lysine Immune Support Powder for Cats, 3.5 oz (Pack of 4) - Image 5](https://m.media-amazon.com/images/I/51HUJauMCIL.jpg) ## Available Options This product comes in different **Size** options. ## Questions & Answers **Q: I don't feed my cats canned food. Will this work on dry food? If so, how do you do it? Do you wet it at all?** A: This product will work well when added to canned food. Cats should Never be fed dry food only. Dry food does not contain enough water to maintain a cat's health. Dry food is made for people and not cats. It is made to be convenient. Cats are desert animals and will not drink enough water on their own. Cats need all the water you can get into them, to avoid long term health problems such as diabetes and the dreaded kidney disease. Canned food is more like the prey cats would eat in the wild and has enough water to maintain the cat's health. I also add water to the canned food. Complete info on this can be found on the Cat Info website, written by Lisa Pierson DVM. **Q: Approximately how many servings are in a container?** A: Depends on the size of your serving. The recommended dose for adult cats is 1000 mg. per day (2 scoops) so...that would be 100 days (2 servings/day) per container. I however, give 1/2 that amount to my cats very successfully. 500 mg.(1 scoop) which means there are 200 doses (servings)or 200 days per container. **Q: Can this product be added to water?** A: I cut up can food and add a little warm water to make a gravy. I sprinkle the Lysine powder on food and wet it with gravy. My vet said a little extra water is good for cats. They love it. I have not used this product with plain water. **Q: Where is this product made? Is any part of it made in China, or does any part come from China?** A: No part comes from China - except maybe the container. You can compare this product to the one offered by vets under the name "Viralys" by Vetoquinol, an acquired Company of Tomlyn Products. The only difference: THE PRICE at my vet is $ 39.--. Both are made in Canada. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Great stuff for feline herpes; plus, a cautionary tale and a solution to a problem *by M***S on November 18, 2014* I purchased this as a replacement for another brand (Viralys) that I had been getting through my vet. One of our kitties had a "cold" when we adopted her. That "cold" just wouldn't clear up. She had a weepy eye and sneezles for weeks. When we took her to the vet, the vet said it was kitty herpes and prescribed the Viralys (at $30 a container). It's l-lysine in powder form; you sprinkle it on the cat food. There is no cure for feline herpes, but l-lysine helps clear up the symptoms. (For those who want to know how l-lysine helps, The Cat Doctor & Friends in Santa Clarita says, "We use L-Lysine to fool your cat's herpes virus into self-destructing by using L-Lysine, instead of another amino acid Arginine, when making new copies of itself. This decreases the amount of herpes virus in your cat's body and hopefully eliminates clinical signs such as sneezing or squinting one eye and reddish brown discharge. Green or yellow discharge from your cat's eye or nose is probably not feline herpes and deserves a veterinary visit.") The Viralys l-lysine powder not only worked great, clearing up the weepy eye and drippy nose within a remarkably short amount of time, it was also loved by all our kitties. (The vet said it wouldn't hurt any of them to eat it.) However, at $30 a container, and with the stupid mistake I made that wasted half a container (see below), I wanted to find a less expensive alternative. And I did. This product, the Tomlyn Scientifics l-lysine, seems to be identical to the Viralys, and costs half what my vet was charging me. My one concern was whether it would taste as good to the kitties, and it does indeed seem to. == My Stupid Mistake and How You Can Avoid It == When I first got the Viralys from my vet, I made a stupid mistake. I used the little scoop that comes with the powder to sprinkle the lysine powder on the cat food, and then I used the scoop to stir the powder into the food. Then I returned the scoop to the container. Those of you who are familiar with good sanitation practices will be able to predict what happened next: after a while, the tiny crumbs of cat food I had inadvertently transferred to the container gave birth to new life. In a few weeks, I saw suspicious little clumps and balls in the powder. I threw out the rest of the powder rather than risk making my kitties sick. After thinking about what I could do to prevent wasting my kitties' medicine (and my money), I realized the solution: put the powder into a shaker container so it never gets contaminated. After shopping around, I purchased the Kaiser Bakeware La Forme Select Sugar/Spice Shaker Set (available here on Amazon), which is just the right size for the powder. I'm using the shaker lid with the largest holes. Now all is well. ### ⭐⭐⭐⭐⭐ Only took about a day to see results *by F***N on August 21, 2014* I have an aging cat and her eyes "drool" brown tears. As a former feral cat, she gets a bit snarfy when I try to wipe her eyes and then thrashes her head around, as cats will do. Now I rarely have to do that. And she sneezes much less often. (Her condition does not respond to antibiotics, so it is not bacterial in nature). I add the directed amount of L-Lysine to about one ounce of canned food twice a day and now her eyes are about 90 - 95% tear free. Only took about a day to see results, as I recall. Another of my cat family has chronic ulcers on his tongue and gums and my Vet wanted to treat him with steroids. I thought I'd try treating him with L-Lysine first, since with his disposition, steroid pills or injections would be extremely difficult to administer. And not good for him long term. To keep my other two cats from stealing the wet food with the L-Lysine, I decided to serve it to all 4 cats. Not one has given the slightest indication that he/she knows that the food has "additives" in it. I have used a wide variety of flavors of a couple of popular brands of the 6.5 sized canned food. Seems that every flavor masks the mild flavor of the L-Lysine, or could be they like the flavor! So I've been using this jar for exactly one month for 4 cats, using 4 rounded scoops twice a day as per package directions. There is still a little left. So if you are treating just one cat, I suspect this jar/container should last about 4 months. Worth the price if it helps. (I haven't had the vet check the cat's mouth yet, but he seems less unhappy. (The cat, not the Vet!) This cat is rather crabby by nature and WILL NOT let me look in his mouth, or even pick him up and I have the scars to prove it! :) However, judging by his behavior, I believe his condition has improved, but I'm fairly certain he still has some ulcers. Can't say I would recommend it for mouth ulcers, but I would recommend this for a cat with teary eyes or runny nose issues not bacterial in nature and not responding to antibiotics. ### ⭐⭐⭐⭐⭐ Great Product for Supporting Our Cat’s Immune Health *by T***S on September 15, 2026* The product arrived on time and in excellent condition. We gave it to our cats every day and it seemed to help reduce the sneezing while also supporting her overall immune health. We’ve been very pleased with the results and would definitely recommend it. ## Frequently Bought Together - Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 4 Pack - Purina Pro Plan Veterinary Supplements FortiFlora Cat Probiotic Supplement for Cats with Diarrhea - 30 ct. 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