Forums » Internal Medicine - Small Animal

Zonisamide and hematologic abnormalities?

    • 1 posts
    March 30, 2014 6:41 PM EDT

    Hi all,


    I have a 7 year old Australian Shepherd on Zonisamide for seizures. Developed seizures around age 5, been on zonisamide for 1.5 years, no seizures since. No other issues or abnormalities with this dog, currently healthy.


    BW over the last few months has shown a downward trend in absolute neutrophil count (went from middle of reference range on initial BW and then went to low end and now slightly below normal). Also, the HCT has extended into the polythemic range over this same trend. My question is - has anyone seen agranulocytosis or hematologic abnormalities with zonisamide? I'm into human medicine as well, and I know agranulocytosis is something we talk about with zonisamide but I can't find any reports of it in dogs.


    Any thoughts are appreciated. I'm inclined to switch to another med or (at least) monitor CBC q6-8 weeks for a bit.




    • Moderator
    • 26 posts
    April 1, 2014 2:05 AM EDT

    I couldn't find any references to this in dogs and have not seen/heard of.  That being said, I'd agree with switching.  I'd add Bromide for 10 days and then stop the Zonisamide.  Phenobarbital can cause bone marrow suppression in dogs and Levetiracetam is also reported to cause blood dyscrasias in people.  Probably should do CBCs q 2weeks for a while.