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To give or not to give Interceptor

May 28th, 2012, 08:09 PM
Ok everyone I have a question for you. I was giving Sasha Ivermectin monthly for maybe 1 year or more, she ran out about 3 months ago. Not sure if the symptoms she had last year are from the "preventitive".

She became lethargic, I thought she was having thyroid problems and she tested ok. At the "lake" last year people commented on her not being her normal self. I thought maybe this was from having Buddy in the house.

Sasha this summer at the "lake" is back to her normal self running playing, swimming non-stop. So is this change because she is not taking the meds anymore? What do you think?

I am asking because when we were at the Vet today they gave me some Heartgard to give her and I don't know whether I should or not.

Sasha is 7 yr and 8 mth old.

May 28th, 2012, 10:55 PM
Ouch! Doesn't anyone have an opinion? Perhaps there will be someone along soon who can help with this decision. Thanks to all who read my thread though I do appreciate that. You can come back later and see what decision I make.

May 29th, 2012, 07:26 AM
pbpatti,sorry I have no opinion,don't know...:o

May 29th, 2012, 07:38 AM
I also don't know patti - but I've edited the thread title to be more precise. Hope that may help.

May 29th, 2012, 07:56 AM
Maybe it would help if you told us Sasha's breed and why you were giving the invermectin? I must say, I'm surprised to see that someone in Edmonton gives it year round. How come is that? :) Not as cold where I am and I only use it in summer, just started two weeks ago.

i mention breed because my sister's Vet advised to NOT give anything with invermectin in it to her dogs, both English Shepherds, both collie types, neither tested for MDr1.

May 29th, 2012, 09:23 AM
Patti, I suppose you could try the Heartgard and discontinue if the symptoms return. If you were giving her Ivermectin by dropper, she likely was getting a larger dose than what's in the Heartgard. Did you talk to her vet about the symptoms and if, given your suspicions, Heartgard might not be a good idea?

As an aside, was she tested for tick disease? Sometimes lethargy is the first symptom we see...

May 29th, 2012, 09:53 AM
Were you using the liquid or paste? It can be tricky to get the dose right with those, and you could have been overdosing?

Yes, breed is important. She could have the mdr1 genetic mutation, which would make her very susceptible to dosage.

May 29th, 2012, 01:45 PM
5 second Google search for "invermectin lethargy":

Side Effects Associated with Ivermectin in Dogs
While ivermectin is considered to be a reasonably safe drug, even at dosages used for treatment of mange in dogs, side effects can occur. In addition, some dogs may harbor a genetic predisposition to ivermectin sensitivity which places them at further risk, especially when ivermectin is used at higher dosages.

Side effects most commonly seen with ivermectin are:

lack of appetite
excessive salivation

As some of you know, Tybalt had an outbreak of demodex (common skin disease caused by mites). After 3 days of being on Ivermectin, I noticed Tybalt was seriously lethargic and when he was up, walked about as if he was drunk. He couldn't walk in a straight line, he would take a couple steps, then stumble down and he kept running into things that were clearly in front of him. His back legs just seem to give out on him. His pupils were also fully dilated. His heart was racing, even when he was at rest. And he was drooling everywhere. His appetite was still the same and he was still drinking water normally and nothing unusual was going on with his bathroom trips other then his stools were a bit soft, but that's to be expected on ivermectin. But his stumbling, lethargy, lack of muscle control and dilated pupils happened over a period of just a few hours and even though he was still eating and such, I got really worried. You could tell he didn't feel good or feel like himself.

After looking up side effects of Ivermectin online, I got hold of the vet ASAP. He told me to stop the Ivermectin and that it was a good thing I noticed the change in his behavior and made the call. A quick trip to the vet to be checked out and a very big watery evacuation of his bowels later (sorry to be graphic!), he is back to normal. Ivermectin interferes with parasites neural functions and very, very rarely, in some dogs will a large enough dosage cross over to affect the dogs neural functions. This is what happened with Tybalt. Thankfully, Ivermectin does not metabolise in the body long and the bulk, over 90% of it, is not absorbed and gets excreted through feces. ....

May 29th, 2012, 05:53 PM
Marko, thank you for adding to my heading (please see my PM to you).

I made an was Interceptor not Ivermectin that I was giving Sasha. Thank you all for your response and help with this.

I really am concerned about giving Heartgard fulltime again. I guess I did not ask enough questions of my Vets in regards to using this product.

Longblades, Sasha is a petite Chocolate Lab weighing in at 24.6kg/50lbs, she lost 2kg since her last visit to the Vet in December. I think that is due to getting more exercise since the weather has changed. Sasha's Vets changed their protocol a couple of years ago and advised to give Interceptor every month rather then just during the summer months. I just went along with it at the time but now I am questioning if this is needed.

Sasha had 2 out of the 8 symptoms; lethargy and depression, I took this as a reaction to having Buddy in the house and her feeling "put out".

HRH, we have had few ticks in Alberta, I know they are there but we have not had to deal with them.....yet!

Sooooooo, the question remains: do I give her the Heartgard during the summer and not the rest of the year? I guess I need to do some research on this. Thanks for your responses so far hope to hear more.

May 29th, 2012, 06:50 PM
There is a test for the gene that causes sensitivity to ivermectin, Patti. The active ingredient in Interceptor (milbemycin oxime) is different than those in Heartgard (ivermectin and pyrantel pamoate). So if she's sensitive to the Interceptor, she may not be to Heartgard.

Most people only treat in the mosquito-ridden months (here it's between April and November) but we give ivermectin all months of the year now as a stopgap against the parasite load the dogs pick up in the yard.

May 29th, 2012, 07:00 PM
Labs are not one of the breeds sensitive to invermectin. My boy is a Lab. I only treat for heartworm from May to Oct., as per my Vet. I am considering not doing even that in order to cut down on the chemicals going into his body. A few doggy friends have discontinued it. It's hard to know what to do when advice varies and preventatives might be as bad as the cure, completely contrary to the old saying.

May 29th, 2012, 10:29 PM
Interceptor can be given at 1/5 the recommended dose. At that dose, it's effective against HW, but not for the other intestinal worms. I might try that. I used to give my 80 lb GSD the 11- 25 lb size (green box). There is an FDA data sheet on this, it's called the Safeheart dose. After I showed that to my vet, she had no problem prescribing the lower dosage.

May 30th, 2012, 11:27 AM
Thank you all for your opinions on this, I am going to continue researching these products and decide whether Sasha needs them or not.

May 30th, 2012, 12:02 PM
If it gets cold during the winter months in Edmonton, you don't need to use the product for those months as there are no mosquitoes, it is spread by mosquitoes. Tiny heart worm larvae are ingested when a mosquito bites an infected dog. Usually treatment is from May-October. (That's if your in a area that gets very cold/snow etc) I am in Montreal and only treat 6 months out of the year. I am using heartgard now, so far so good. I am not treating for fleas and ticks as I have never seen a flea in my life and ticks are not so common here, I check the dogs after their walks. Here is the link for heartgard:

May 30th, 2012, 12:07 PM
Sasha's Vets changed their protocol a couple of years ago and advised to give Interceptor every month rather then just during the summer months. I just went along with it at the time but now I am questioning if this is needed.

My take on vets who do this in areas where year round treatment is not necessary or is an obvious over kill is that they are taking advantage of their clients' love for their dogs and guilting them into spending the money on unnecessary treatments just to line their pockets and more so doing this at the expense of the dog's health and best interest.

These meds can be extremely hard on a dog's body. They should be taken very seriously and not given out like candy. They can be very taxing on a healthy dog's system, especially a dog with any health issues. I know many people who no longer do any of them at any time and opt for more holistic ways to repel the bugs. Even testing regularly for HW as opposed to giving the regular preventative as it can be that hard on a dog.

Obviously this is a very personal decision and you need to do what you feel comfortable with. It's very good that you are going to research this, just like with vaccinations there is lots of material on this out there.

You may also consider consulting with a local holistic vet if there is one available. Even consider switching vets if necessary. Don't get stuck on a bad vet just because you have been with them for a while.

May 30th, 2012, 04:46 PM
Thank you all for your opinions on this, I am going to continue researching these products and decide whether Sasha needs them or not.

Do check out this website and related links during your research:

(I'm actually kinda amazed that a vet in Edmonton would recommend ANY heartworm preventatives, never mind year round. HW is extremely rare in Alberta).