---
product_id: 1865632
title: "Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz"
brand: "tomlyn"
price: "€ 39.19"
currency: EUR
in_stock: true
reviews_count: 10
category: "Tomlyn"
url: https://www.desertcart.it/products/1865632-tomlyn-immune-support-daily-l-lysine-supplement-fish-flavored-lysine
store_origin: IT
region: Italy
---

# Palatable fish flavor cats love Vet-formulated L-Lysine powder Supports immune & respiratory health Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz

**Brand:** tomlyn
**Price:** € 39.19
**Availability:** ✅ In Stock

## Summary

> 🐾 Keep your cats feisty & flourishing with every sprinkle!

## Quick Answers

- **What is this?** Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz by tomlyn
- **How much does it cost?** € 39.19 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.it](https://www.desertcart.it/products/1865632-tomlyn-immune-support-daily-l-lysine-supplement-fish-flavored-lysine)

## 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:** Fish-flavored powder ensures easy, stress-free daily dosing without fuss.
- • **Flexible Daily Dosage:** One to two scoops daily tailored for kittens and adult cats’ immune needs.
- • **Cost-Effective Wellness:** Premium quality at half the price of vet brands—keep your feline family thriving without breaking the bank.
- • **Vet-Trusted Immune Boost:** Clinically formulated since 1976 to support your cat’s natural defenses.
- • **Respiratory & Eye Health Support:** Helps manage sneezing, watery eyes, and respiratory discomfort for all ages.

## Overview

Tomlyn Immune Support Daily L-Lysine Supplement is a vet-formulated, fish-flavored powder designed to enhance cats’ immune and respiratory health. Ideal for managing common feline issues like sneezing and eye irritation, this easy-to-administer supplement supports cats and kittens of all ages. Trusted since 1976, it offers a palatable, cost-effective solution to keep your multi-cat household healthy and vibrant.

## Description

desertcart.com : Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz : Pet Antioxidant Nutritional Supplements : Pet Supplies

Review: Support for feline immune system in a multicat household - We have a three cat household, and it's important to us that all three cats stay healthy. Lysine is a good supplement to support immune function in felines, and all three of our roommates get a good slosh of this stuff with every meal. NOne of them have ever balked at the taste or texture, and they gobble up all their food. They've stayed healthy and feisty and very much themselves, and what could be better? Check with your vet, but lysine has been very good for our household.
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.

## 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 | B00BERPOP4 |
| ASIN  | B00BERPOP4 |
| Age Range Description | All ages |
| Best Sellers Rank | #24,043 in Health & Household ( See Top 100 in Health & Household ) #24 in L-Lysine Nutritional Supplements |
| Brand Name | TOMLYN |
| Breed Recommendation | All Breed Sizes |
| Care Instructions | Store in a cool, dry place. |
| Color | multi |
| Customer Reviews | 4.6 4.6 out of 5 stars (5,402) |
| Date First Available | February 8, 2013 |
| Date First Available  | February 8, 2013 |
| Department | Unisex-Adult |
| Department  | Unisex-Adult |
| Directions | Tomlyn® Immune Support L-Lysine Supplement Powder for Cats provides support to your cat's immune system and eye health. If your cat suffers from an upper respiratory infection or from feline herpes then providing your cat with l-lysine can prove essential to their well-being. This amino acid contributes to the relief of eye irritation, cold sores, sneezing, difficulty breathing and more. Tomlyn® I… |
| Included Components | Key Features: Veterinarian formulated trusted since 1976 Supports a healthy immune system and normal eye health and function Tasty chicken and fish flavor |
| Is Discontinued By Manufacturer  | No |
| Item Dimensions LxWxH | 3 x 2.75 x 2.75 inches |
| Item Package Dimensions L x W x H | 3.03 x 2.68 x 2.6 inches |
| Item Weight | 0.4 Pounds |
| Item model number | 433343 |
| Item model number  | 433343 |
| Manufacturer | Tomlyn |
| Manufacturer  | Tomlyn |
| Manufacturer recommended age  | 1 month and up |
| Material | Plastic |
| Model Name | Tomlyn Immune Support L-Lysine Supplement Powder for Cats, 100g |
| Number of Items | 1 |
| Product Dimensions  | 3 x 2.75 x 2.75 inches; 6.4 ounces |
| Size | 3.5 oz (1 Pack) |
| Specific Uses for Product | Active |
| Target Audience Keyword | house-cats |
| Warranty Description | See Manufacturers Website |

## Product Details

- **Active Ingredients:** sodium acid
- **Brand:** TOMLYN
- **Flavor:** Chicken and Fish
- **Item Form:** Stick
- **Item Weight:** 0.4 Pounds

## Images

![Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz - Image 1](https://m.media-amazon.com/images/I/61QaCsgTxdL.jpg)
![Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz - Image 2](https://m.media-amazon.com/images/I/61+8Kink6FL.jpg)
![Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz - Image 3](https://m.media-amazon.com/images/I/61VhiZns-0L.jpg)
![Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz - Image 4](https://m.media-amazon.com/images/I/61SIYHQn32L.jpg)
![Tomlyn Immune Support Daily L-Lysine Supplement, Fish-Flavored Lysine Powder for Cats and Kittens, 3.5oz - Image 5](https://m.media-amazon.com/images/I/61n0UqI-lFL.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

### ⭐⭐⭐⭐⭐ Support for feline immune system in a multicat household
*by A***R on February 8, 2026*

We have a three cat household, and it's important to us that all three cats stay healthy. Lysine is a good supplement to support immune function in felines, and all three of our roommates get a good slosh of this stuff with every meal. NOne of them have ever balked at the taste or texture, and they gobble up all their food. They've stayed healthy and feisty and very much themselves, and what could be better? Check with your vet, but lysine has been very good for our household.

### ⭐⭐⭐⭐⭐ 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.

### ⭐⭐⭐⭐⭐ Work quickly
*by A***N on September 15, 2025*

I received my order quickly. I couldn't find the other immune supplement that i ordered last time so I decided to go with this one. My cat has FIV. To my surprised this immune supplement worked on the very first day. The last supplement i had used took a week to start to work for my poor boy. So I am very pleased with my choice to go with this. My boy loves the flavor, gives him a nice soft shiny coat as well. Helps with his eyes, nose, his breathing and anything else that helps him with. It is a white power and has a spoon that comes with it. The size of the jar is pretty decent size. He gets it every morning in his food. I definitely recommend this!

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*Product available on Desertcart Italy*
*Store origin: IT*
*Last updated: 2026-03-10*