Comments on: Dogs on drugs: FDA warns of dangerous drug interaction

By: Fran

Fran — Sat, 13 Feb 2010 23:42:54 +0000

Last month I noticed My 3 1/2 year old doberman
sitting on my bed looking rather strange. Then he started to twitch, seizure like, mostly his face and ears. The rest of the evening he was not himself, decreased energy. I had given him
comfortis and hearguard plus that day. He had been on this for approx 6 months. Looking back I think I have seen similar reaction but not so pronounced and it did not last long that I did not think anything of it. This week I took a new rescue dog to a new vet because I have relocated. This vet does not prescribe comfortis. So I decided to research the drug..
I will only be using topical flea protection from now on.
Fran

By: Edna

Edna — Mon, 18 Jan 2010 20:33:11 +0000

Just my two cents, but I will NEVER give Comfortis to a dog again. My 13-year-old dog (granted, she was 13, so the fact that all these problems developed just after she went on Comfortis could be a coincidence…but I personally do NOT think so) developed all sorts of odd problems after doing on Comfortis last summer. Within six months, she was dead. Prior to that, she was totally healthy. After going on Comfortis, she developed trigeminal neuropathy, a disease in which her massiter muscle just wasted away to nothing, leaving strange and alarming (to me, anyway) indentations in her head. This was the first truly alarming sign. She also developed discoid lupus. Then about six months into this, she really sent downhill and developed neurological symptoms over the course of several weeks (which at first I didn’t recognize as such—I thought it was just arthritis), which drastically got worse in the last 4 or 5 days of her life and ended up that she couldn’t walk, couldn’t blink, had a seizure, and in the end, had to be humanely euthanized. After extensive tests (bloodwork/x-rays) revealed only a slightly enlarged liver), and after she ended up having the seizure, inability to blink, etc., my vet concluded that it was a brain tumor which didn’t show up on the x-rays. Now: he feels that all of this had NOTHING to do with the Comfortis, and I should add that he is a fantastic vet who I’ve been going to for 14 years, and usually I trust his opinion. But in this case, even though my dog was old, she was FINE before the Comfortis and it is just quite a coincidence if it had nothing to do with all these strange things happening. I will never use Comfortis again and strongly recommend that other folks think twice about it.

By: Adriane

Adriane — Mon, 07 Dec 2009 17:42:48 +0000

last month my mom gave my dog butters comfortis and heartgard and he kinda couldnt jump but he got better in a day or two, that was the first and only time we gave him comfortis this month my mom gave him his heartgard and he got really bad. we couldnt find a vet open and thought he would be ok. well he wasnt and it was the most horrifying thing i have ever seen i do not want to see my dog in that much pain

By: The OTHER Pat

The OTHER Pat — Sun, 29 Jun 2008 20:48:12 +0000

I hope Benny recovers and is okay!

You should report this as an “adverse event”. Here is a page on it:

http://www.avma.org/animal_hea.....events.asp

By: Pam Goins

Pam Goins — Sun, 29 Jun 2008 19:23:37 +0000

My dog Benny is taking Ivermectin for congenital parasites, he also received a dose of comfortis last night (both prescribed by vet). This morning Benny was panting, drooling, and ataxic, after an emergency visit to the vet I was told these meds should not be given together.

By: Gina Spadafori

Gina Spadafori — Fri, 27 Jun 2008 15:16:13 +0000

When I was visiting my rancher friend in Texas, we went to the feed store. (Yeah, party down in ranch country!)

For the first time I saw Ivermectin in bottles face to face. (Our citified local feed store doesn’t carry it.) And I thought, as I always do, that it would be better for veterinarians to help their clients skip the brand name and protect their pet. ESPECIALLY in poor rural areas with bad heartworm problems, like where I was in Texas.

By: slt

slt — Fri, 27 Jun 2008 14:35:23 +0000

I do similar to what you do H and for the same reasons. And yes, have personally corresponded with (or seen on boards) several Vets who give the mange Ivomec dosage for HW prevention. Now some people are concerned that HWs are developing a resistance to Ivermectin and I wonder if that goes beyond the usual “parasites eventually develop resistance to drugs in widespread usage” and crosses into so many people overdosing their dogs as a contributing factor.

By: H. Houlahan

H. Houlahan — Fri, 27 Jun 2008 14:20:00 +0000

Agreed about the off-label ivomec. I can’t tell you the number of times that, when confronted with the math (here’s the dose in mcg per kg of Heartguard; here’s how you dilute the ivomec to get to that dose, or close to it, look I’ve shown my work), the guy who is giving his Sheltie a full ml of cattle ivomec every month will object that MY VET TOLD ME THIS IS THE DOSE.

FWIW, I do the off-label ivomec, and don’t go through the bother of diluting with glycerol of propylene glycol. Every dog gets an overdose — one small drop of ivomec on a biscuit. But every dog I own has either been tested, or is known by parentage, to be MDR1 normal/normal. Including the German shepherd! I keep Heartguard on hand for the rescue fosters that come in with unknown pedigree for MDR1, or are known to be at risk for the mutation.

If Heartguard wasn’t overpriced on such a robber-baron scale, the bottle of cattle wormer in the fridge wouldn’t be such an obvious solution for so many rural dog owners. I just wish they’d do the math instead of substituting the letters “DVM” for research, and I wish they’d get at least dogs from at risk breeds or suspect mixes tested for their mutation status.

(I’m also a bad, bad, disobedient consumer, and buy the largest vials of Frontline from Australia, then carefully measure with an insulin syringe and split the doses between 2-3 smaller dogs. Cuts my tick control costs by well over half.)

By: slt

slt — Fri, 27 Jun 2008 11:00:41 +0000

My first thought when I read this was that MANY people using “extra-label” Ivermectin for HW prevention are mistakenly using the mange dose which is a much higher dose than needed for HW prevention. I see this all the time on various boards. Granted, they are overdosing monthly - not daily - but OTOH they are unaware they are overdosing.

By: Christie Keith

Christie Keith — Fri, 27 Jun 2008 03:47:58 +0000

All dogs. But I can’t help but think dogs with the MDR-1 mutation would be at greater risk. I believe there is a study underway to look at this issue more carefully now that this interaction has been identified.