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Australian Shepherds and seizures
BaileyBooca posted:
My husband and I rescured a 1-1/2 yr australian shepherd in October 2010. Unfortunately "Ozzie" has had seizures since we got him... one in November, one in December. Then cluster seizures begain in January (six) and then three weeks later in February (nine). Ozzie is on pheno and has his dosage increased to 60 mg twice a day. So we're hoping for the best. The last two months seem to coincide with his monthly Interceptor med and now I'm beginning to think that this might be a contributing factor. I have requested a test from Washington State University to see if Ozzie has the MDR1 gene. If he does then we can discuss that later, but I wanted to know if there is anyone out there that also give Interceptor for heartworm and their dogs may have had a reaction to that as well.

Hoping for the best and thanks for any input.
Violets_are_Blue responded:
In general, the gene that affects collies mostly is sensitive to the chemical in Iverhart/Heartgard medication (ivermectin), not Interceptor (milbemycin oxime). We actually prefer to start and keep collies and herding breeds on Interceptor because of this. However, it does say that Interceptor can have seizures as a side effect so it could be the contributing factor, just not in the way you were thinking. The test from WSU is actually a good idea as, if he is negative for the gene, you can try Iverhart/Heartgard in place of the Interceptor. If he is positive though, it would be best to stay away from both medications and use Revolution or Advantage Multi (both topical).

Hope this helps and you find something that works for Ozzie.
Ernie Ward, DVM responded:
Sorry about your baby. The MDR1 test is an excellent idea! (and one I wish more pet parents pursued)

Talk to your vet about multi-modal therapy. We often add potassium bromide in an attempt to lower PB dosage and reduce seizure frequency. Also talk with your vet about adding omega-3 fatty acids to the diet (1-2 grams DHA/EPA per day). Finally, talk about some herbal treatments and if they're a good fit for your dog.

As a general rule, no, Interceptor is not typically related to seizure activity in dogs.

Good luck,

Dr. Ernie
BaileyBooca replied to Ernie Ward, DVM's response:
Thanks... I will mention these to my vet. Is there a specific dog food that you recommend that contains the omega-3 fatty acids or is that something I can get at the pharamacy?
BaileyBooca replied to Violets_are_Blue's response:
Thanks, I'll keep you all posted with the results on the MDR1 test.
BaileyBooca replied to BaileyBooca's response:
Ozzie's MDR1 test result was Normal/Normal which indicates that he does not have that gene. As for his seizures - yesterday was three weeks since his last and so far so good.


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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