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Felisyl® Immune System Support Granules (3.5 oz)

Item Number: FELISYL35
Regular Price: $12.00Sale Price: $9.99
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Felisyl® is a supplement that contains the amino acid L-Lysine for use in cats and kittens for conditions responsive to L-Lysine. L-Lysine is an essential amino acid, which means that your petís body needs it, but canít produce it, so this supplement is a perfect choice to provide that necessity.

Now available without a prescription, L-Lysine HCL Immune System Support for Cats helps keep your cat healthy by supporting the immune system naturally so that it can function normally and produce antibodies. Felisyl L-Lysine HCL Immune System Support for Cats also helps maintain healthy tissue, supports respiratory health, and may even help with your catís vision. The L-Lysine is in a palatable poultry and fish flavored base making these granules easy to give to your cat, just sprinkle over or mix with food.

For Use In: Cats

Usage Information

Sprinkle measured amount over cat’s food and mix in.

Age of Cat Morning Evening
Under 6 months 1/2 Scoop 1/2 Scoop
Over 6 months 1 Scoop 1 Scoop


Guaranteed Analysis per (1 cc Scoop)
Moisture (max) 1.1%
L-Lysine 78% (250 mg)
Ingredients: L-Lysine, Proprietary Poultry and Fish Flavoring, and Sucrose.

Customer Reviews

DISCLAIMER: The results described on the testimonials on this site, are the individual experiences and personal opinions of those who have purchased and used the products. These testimonials are not intended to make any claims that the products can be used to diagnose, treat, mitigate, cure or prevent any disease or medical condition.Click here to see all reviews
4.67 rating based on 21 reviews
Only product to help my pet. by Buddy from Jackson, TN08/21/2013

This is recommened by my vet. Only thing that can build his imm. system

Felisyl by Sandy from New York12/14/2012

Used the product for my cats who were sneezing and it seemed to help them a bit. Their eyes are no longer dripping as they were, so perhaps it works as stated.

by Barb12/03/2011

I give this to my 4 cats on a daily basis. Very pleased with results.

Felisyl Immune System Support by Queen B from New Castle, DE11/23/2012

It seems to work as well as other brands. It dissolves better in food than other brands. It's slightly cheaper, however, I believe the dose is slightly larger.

my cats love this by Karen11/30/2012

this product is very palatable, one of my cats even tries to lick it right out of the jar!

Good product! by FosterMama from Boston09/24/2013

Easy to give to kitties with a little bit of wet food or even add a little water. My cats love it and it keeps their sniffley episodes down. Love it!

My Ferals Like It by kirvls from Colorado09/17/2013

They like the flavor and it gives them the Lysine they need.

Felisyl by Pam from Enuclaw, Wa03/15/2012

This product helped my cat conquer his sinus condition better than a whole series of antibiotics. It seemed to greatly improve his immune system.

Felisyl by jj05/20/2013

works really great it really helped and looking forward to ordering more in the future

Not the answer by Pauladimi from Las Vegas Nevada02/26/2013

I have cat with diabetes and allergies. it does not help him at all. I was hoping to avoid going to the vet and getting him a steroid shot

by from 03/04/2012

My cat does not like "treats" so I bought the powder version of Felisyl and put it in his food. He does not know the difference and he eats it! YEAH!!! No force feeding!!!! Something you do not want to do with a cat. (CLAWS)

be by buyng from moreI


by Benji's mom03/04/2012

The cat loves his food with sprinkles of FeliSyl on top and has zero hair balls if given daily.

product probably fine but the cat won't get near i by max's mom from west palm beach04/05/2012

They say it is flavorless and odorless. The cat doesn't think so. Right now I am back to crushing human lysine tabs and then mixing them into soft food to hide it. Right now, that is fine but may try sneaking this into his soft food again soon to save me the trouble of mashing his pills. Too early to tell how this will work.

Kitties Are Crazy for It! by foxfyreutk from Tennessee12/31/2013

I had been mixing granules into canned cat food, but that is a very expensive treat. Thought I would try the kitty treat version. Both my cats are crazy for it. They try to open the bag themselves and remind me it's time for their treat. Far easier and not nearly as expensive as the powder.

ease of use by Query11/29/2013

So can I just add this to dry food left out for self feed of 1 to 16 cats?

it works great by cathy from indiana08/20/2013

my cats caught the feline cold from a new cat I got they were all sick. I looked up what to give them to help them. this is the lysine and its in this product works great to keep it under control, nobody has gotten sick again . I put it in there food and they don't even know they are eating it.

Good product by Dawn from New York, NY03/10/2012

I used to buy a more expensive brand, then found this one. The color turned me off a little (I'm used to a white powder), but my cat doesn't know the difference and I have no problem putting it in her food.

by Katzhse from Tucson, Az11/24/2012

I have been sprinkling this on their dry food so at least they get some when they eat. If i put it in the wet food they won't eat it.

oral powder by Anita10/24/2012

This works well mixed with wet food...we do have a couple that will eat it right out of the bowl before the food is added....it does a good job of helping to control virus'

FABULOUS Felisyl L-Lysine Granules by iluvcats from Louisiana01/22/2015

This product is EXACTLY what I have been needing for my two kitties! These granules have proven to be the very BEST product to deliver the 250 mg of L-lysine necessary for my cats health needs. I was using the L-Lysine in a pump, which is tuna flavored. The extra strong smell seemed to be a deterrent, even though they both love seafood flavored wet food. They would walk away and leave the food to spoil, causing me to have to open another can of food. When one of my cats recently had a herpes breakout (sniffles & runny eyes) I had to put the stinky tuna flavored thick L-lysine from the pump on my finger and stick it in her mouth to insure that she was being treated properly. The granules don't have a scent; both of my cats lap up their wet food; and my sweet kitty is now 100% well in less than 2 weeks! Like normal, I put the wet food in the bowl with water; mix it up; then put the tiny scoop of L-lysine granules on top; gently stir so that the granules are just barely mixed in - they lap it up and get 100% of this vital nutrient! I HIGHLY recommend this product! It is AWESOME!!

Good stuff! by Kaye6311/13/2012

My cats loved this and I will be ordering it again!

Works very well by moms_2slow from Wilton, CA08/16/2012

This product has a very yeasty smell, so my cat loves it. He has slowly improved on the product, so I am quite happy.

Great product by Bruiser04/13/2014

When shopping for a Lysine supplement for my FIV positive cat I had been used to the Viralys gel. Seeing as how the Felisyl brand was half the price I thought I'd give it a go. I feel that the powder allows me to be more accurate in the dosage. And my cat has transitioned very well. I will definitely be back for more when my supply runs out.


Questions and Answers

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