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L-lysine In Purina Pro Plan

Discussion in 'Cat Nutrition' started by Tango&Cash, Mar 15, 2019.

  1. Tango&Cash

    Tango&Cash Thread Starter TCS Member Kitten

    Mar 15, 2019
    Good Morning,

    New member of the forum here with two new 9 yo Siamese cats recently adopted from the local shelter. Both cats are suspected of having FHV since pretty much all the cats at the shelter get it (terrible I know) and have had URIs with running eyes, sneezing etc. It appears we've got that under control for now but the vet strongly recommended getting them on a L-Lysine treatment routine to help manage future flare ups. It's been a real challenge trying to get them to eat the lysine since they hate all the treats that have it. I've read up on that here and gone over most of the common conversations about L Lysine on the webs, I think we've got a decent strategy to try out.

    My big question, which has been difficult to find an answer to, is: How much L-Lysine is in their food?? We feed them Purina Pro Plan and it lists L-Lysine as an ingredient but I can't find anywhere saying how much. I'm guessing it's not the 500mg/day the vet recommends but I'd sure like to know, life would be pretty simple if I could be sure they were getting enough from the food that I didn't need a supplement. Anyone looked into this before?


  2. verna davies

    verna davies TCS Member Staff Member Forum Helper

    Feb 23, 2016
    Wales uk
    I have done a few searches but whilst they list L-Lysine as an additive like yourself cant find any mention of the quantity. I think your best bet is to go to their website and contact them with the question.

  3. m3rma1d

    m3rma1d NeoMaxiZoomDweebie Super Cat

    Oct 12, 2018

  4. Faikey

    Faikey TCS Member Young Cat

    Mar 15, 2019

  5. Faikey

    Faikey TCS Member Young Cat

    Mar 15, 2019
    500 mg a day is from a study done in 1974 based on 10 cats.
    Lysin in felines has no actual evidence to reduce flareups. It's also processed by cats in mere hours and can dangerously hurt their Argentine levels by sudden elevations in blood plasma due to the fast metabolic process lysine has in cats.

    There is evidence at multiple levels that lysine supplementation is not effective for the prevention or treatment of feline herpesvirus 1 infection in cats. Lysine does not have any antiviral properties, but is believed to act by lowering arginine levels. However, lysine does not antagonize arginine in cats, and evidence that low intracellular arginine concentrations would inhibit viral replication is lacking. Furthermore, lowering arginine levels is highly undesirable since cats cannot synthesize this amino acid themselves. Arginine deficiency will result in hyperammonemia, which may be fatal. In vitro studies with feline herpesvirus 1 showed that lysine has no effect on the replication kinetics of the virus. Finally, and most importantly, several clinical studies with cats have shown that lysine is not effective for the prevention or the treatment of feline herpesvirus 1 infection, and some even reported increased infection frequency and disease severity in cats receiving lysine supplementation.

  6. cheesycats

    cheesycats TCS Member Alpha Cat

    Jan 29, 2017
    Unless you email them and ask you probably won’t know just how much there is. If it’s far on the ingredient list there’s likely next to none in it. Similar to when u see glucosamine in foods, it’s just there to make the food look more appealing but usually is in such small amounts it doesn’t have much effect.

  7. Jem

    Jem TCS Member Top Cat

    Aug 6, 2018
    Hi! I saw this thread and before I posted, decided to e-mail the company of the food that I feed my kitty, which also has L-Lysine in the ingredients. It's not the same company, but if you did the same I'm sure they will respond. The company I e-mailed responded, and sent this about how much is in their food: Feline Calm formula: L-lysine 4.1 g/1000 kcal or 1.45 g/cup (1 cup = 96 g.).
    I have zero math skills LOL! so I'm not sure exactly how much this is but, they did respond, so that's good.

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