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Cat Allerty to Fleas, Flea Medicine (Hartz, Advantage)
Plaid_Lace posted:
Hello! I have a cat who is extremely allergic to flea bites, and Hartz flea drops.

Fleas - He scratches til he has huge scabs and he looks unkempt and unhappy.

Hartz Flea Prep - After one overnight a few years ago, we came home to a huge oozing, bleeding sore he was scratching on his neck where we put the flea drops.

We have been using Advantage for dogs (we have three cats) for several years, but now kitty scratches his neck endlessly after we use the drops. I tried him on allergy pills 2x/day as prescribed by his veterinarian, and kept the Advantage the same last month. (We weren't sure if it was environmental allergies (Ragweed, etc.) or the Advantage. Well, this month he's scratching more - to the point of several small scabs around his neck, even 3 weeks after I applied the drops.

I looked online, and see that in addition to Frontline there's a generic (Fiproguard), which I'm wary of buying because he's so allergic... what if the inactive ingredients are what's causing the problem?

So I guess we stop the reaction with prednisone, then do a trial of Frontline for the three cats, for a month or two, and see what happens.

Any direction you can give as per what next? What happens if he's also allergic to Frontline? Which (Advantage vs. Frontline, Dog vs. Cat) would you use if he were your kitty?

Thank you.

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Plaid_Lace responded:
  • Allergy*
    Drew Weigner, DVM, ABVP responded:
    It sounds like your cat is reacting to something, whether it's fleas, flea medication, or something else. Of course, there are other things that can cause skin lesions, like infections, tumors, etc. If your veterinarian has determined it's some type of allergy, oral Prednisolone may help, but long-acting injections usually work better and are safe to use in most cats on an occasional basis.

    Drew Weigner, DVM, ABVP
    The Cat Doctor
    Board Certified in Feline Practice
    Plaid_Lace replied to Drew Weigner, DVM, ABVP's response:
    Dr Drew -

    Thank you for your answer. Yep, our vet has determined that this kitty is allergic to a lot of things. He's being treated with an allergy medication twice/day, and oral Prednisolone for acute attacks. I wasn't aware there's an injection we can give him that's long-lasting. I'll ask our vet about it.


    William Draper, DVM, better known as "Dr. Will," is a well-known small animal practitioner in the Atlanta, GA area. He grew up in Inglewood,...More

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