What Type Of Heartworm Medication Is Safe To Use For Aussies?

by Melissa
(Monmouth, IL)

My vet had mine on Heartguard, my pup started having seizures a day or so after the 1st of month dose, after some research. I found that Aussies should not take Heartguard. After more research found that Aussies and herding breeds have a sensitivity to Ivermectin, which is in Heartguard. Inquired as to what I should give him for protection besides Heartguard. Interceptor was mentioned but never was offered to start my Aussie on that medication. When I finally questioned about changing, was told it was on indefinite backorder.

So all this time, because I'm a relatively new dog owner. My Aussie has been on phenobarbital for seizures that could have been avoided! Needless to say, I'm a little upset that my pup has to go through this. So my question, what are other Aussie owners using for heartworm protection? I desperately want my Aussie off phenobarbital and seizure free. I will not give him another dose of Heartguard!!! Any suggestions? Thank for any help anyone can suggest.

Aussie lover

Comments for What Type Of Heartworm Medication Is Safe To Use For Aussies?

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Heartworm medication
by: Heidi M


I am so sorry to hear that. I have a 2 year old Aussie and she is not on any heartworm med yet because I have read the reports. I asked my vet and she said it is not a problem b/c it has a low dose. I refuse to take the chance. I was quite surprised that she actually said that. So I am sorry I can't offer you advice. I would love to learn of another option. Once again I hope your sweetie can recover. Did your vet say that the seizure will go away or that the meds caused him to have epilepsy?- Best Wishes

What type of heartworm
by: Heidi M


I was just doing some research and I came across this...

Acute ivermectin toxicity paralyzed Charly, who was first treated with lipid infusion and had to be placed on a ventilator to help him breathe. On May 26, UF veterinarians disconnected the ventilator and Charly went home with his owner June 1, recovered from the ordeal.


Hope it can help!

by: jcrply

Glad to hear you are doing research. I have been using Interceptor. Novartis is supposedly going to resume manufacturing it sometime in the future. I still have some Interceptor because I always cut the pills. The medication in Interceptor is Milbemycin Oxime. Do some research on that on your own. Include the FDA (Food and Drug Administration) website. The FDA recommends 0.05 mg Milbemycin Oxime per pound of dog weight. So a 40 pound dog needs 2 mg per month. The smallest Interceptor pill has 5.75 mg. (They sell that for an 11-25 pound dog!) They put in so much extra so it will also kill intestinal parasites. My vet recommends TRIFEXIS while we wait for Interceptor to become available again. Trifexis is also Milbemycin Oxime. The difference is that Trifexis also has Spinosad in it. The Spinosad is added to kill fleas. If I run out of Interceptor, I will use the Trifexis, but I will also cut those pills since they too have 5 times as much milbemycin oxime as is needed for just heartworm. Even cutting these pills in half gives the dog a lot more than he/she needs for just heartworm.

by: gayle--big run aussies

There is a new product on the market called Trifexis. You can also use Sentinel. These products are more expensive than Interceptor and also have a flea preventative in them that I, personally, object to, but they do not have ivermectin. The other option is to have your dog MDR1 tested for drug sensitivity to see if that is the problem. The testing is done through the University of Washington veterinary school. Good luck.

Heartworm Medication
by: Anonymous

My aussie and lab are both on Heartguard Plus with no problems other than diarehha the day of. I would like to hear what other aussie owners are using.

Heartworm preventative
by: Colin

My mini Aussie has been on Sentinel for a year and we just recently changed him to Trifexis. Neither preventative medication had any adverse effect on him. He's happy, healthy and heartworm free. (2 years)

Sentinel back in production
by: Jen J

I just got back from the vet (I have two Aussies). Interceptor is not coming back, but Sentinel just started back up (May 2013). Sentinel is Interceptor plus a flea prevention product. So far so good. They've also promised to keep the price stable, since they lost a lot of customers when production ceased, and they need to win them back.

Heartworm medication
by: Carol

Thank you all for your posts, we are taking our 15 week old Aussie to the Vet next week for her first check up since buying her last week.
I did read some articles regarding Aussies and heart worm medication and was wondering what I was going to do.
Your information has helped me.

Be careful of ant poison containing abamectin!
by: Francesca

Hi Melissa, I am so sorry to hear about your aussie's seizure. Since your dog has this sensitivity, please be aware of other things that contain a compound called abamectin which is related to ivermectin. Some ant poisons contain this ingredient, and my aussie stepped in it, licked his paw and went into seizures. The Washington state lab (mentioned by my breeder Gayle of Big Run Aussies in this post hi Gayle! ) can be reached at http://www.vetmed.wsu.edu/depts-vcpl/ for the test kit. Wishing you the best.

by: Colin

I've used Trifexis for 2 years now with my 2 year old Mini Aussie. Absolutely no problems what so ever. It smells really bad. A little cheese and he woofs it right up. :) Sorry you had a bad experience. :( I do pray all is well now. <3

A veterinarian's opinion
by: Anon

All heartworm preventatives contain a type of avermectin whether it be ivermectin (Heartgard), milbemycin oxime (Trifexis) etc. ONE of the drugs MDR1 dogs can be sensitive to is an avermectin. Other drugs include Immodium and some chemotherapy drugs; there are others. At the doses used in veterinary prescribed heartworm prevention products, even MDR1 positive dogs can receive them as heartworm prevention safely. Is it impossible for a dog to have a seizure from properly prescribed heartworm prevention? No. That being said, it is unlikely. If you are concerned, have your dog tested for the gene through Washington State then have a conversation with your VETERINARIAN or even multiple veterinarians if you want a second, third opinion. There is so much dangerous and inaccurate information floating around the web I beg you to talk with someone who has the education behind their opinions (ie. a veterinarian.) If you don't trust your veterinarian, find a new one! For the woman with the seizing dog: My opinion is that you should see a boarded internist or neurologist - that is the ultimate level of care you could get for your dog.

Re: FDA Page
by: CaliAussieGal

The FDA page says (referring to Interceptor) "The tablets supply the recommended minimum dose level of 0.5 mg milbemycin oxime per kilogram (0.23 mg/lb.) of body weight."
So, dogs need .5mg, NOT .05mg per KILOGRAM, not POUND. This changes the numbers a lot.
I just wanted to get the correct information out there so no one thinks they are treating their dog when they aren't actually!

No heart worm poison given
by: Sharon

I have a 9 year old Aussie boy and an 11 year old mixed girl, and neither have been on any heartworm poison for the past 8 years. I object to giving my dogs pesticides or any other harmful chemicals. Call it heartworm "medicine" all you like, but it is nothing but poison. My dogs are fed good, healthy, natural food and are cared for as naturally as possible. My vet can't believe my girl is 11 years old because of her outstanding health and appearance, and she understands and respects my choice not to poison them. They are tested every year and have always tested heart worm negative. I can't understand why a dog's good health should be compromised by poisoning them unnecessarily, so will not do that to them.

Interceptor can be purchased in Australia
by: Anonymous

You can buy interceptor with tapeworm preventative at petshed.com . It is sold in Australia and Canada but not in the US.

I am with you. I would opt to not give my asussie anything rather than have her on a medicine that made her that sick. I hope yours is better soon :)

by: Anonymous

I have had 3 friends who have used Trifexis and all of their dogs have had seizures. Aussies have a chemical imbalance in their brains and the Trifexis is very harmful to them.

by: Em

We have been using Trifexis for our aussiedoodle. I'm thinking about trying Sentinal. He's only 9 months old. We would consider going all natural, but that's how we lost our lab to heartworms in the past. We won't do that again. She lived a long life, but she had heartworms in the end. We do live on a farm, so our animals are exposed to more (they aren't apartment animals).

by: Kat

When Interceptor was no longer available my vet recommended this product. I hesitated but live in an area with a lot of mosquito. I gave two monthly doses in the fall and began again in June of the following year. After four more doses my dog became completely deaf. I feel so terrible that I wasn't more careful. His life is changed completely, so I am going back to a medication like Interceptor.

Vets should be more cautious and ask to monitor for symptoms.

Trifexis can cause dog deaths
by: Anonymous

Here's a link to a story on dog deaths caused by Trifexis.


Btw, we're on Sentinel, but my dog still got heart worms. No great solutions out there.

by: Anonymous

Be careful with the Trifexis - If you go to their website the advise to use caution in using it in epileptic dogs!

5 month old mini aussie - revolution
by: Julia

Has anyone used Revolution topical medication? I would love to know if anyone has had problems with this medication.

by: Sandi

We have been using vet recommended Revolution since the production of interceptor stopped. All good on both of my Aussies for a long time. I would caution not using any med for this disease. I know someone who's 2 yr old shep has it and it is tragic to watch the dog go through this illness. be careful.

Advantage Multi for dogs
by: Indianapolis,in.

We adopted an Aussie, she is now a year and a half old. The rescue highly recommended Advantage multi for dogs. She just had her second checkup and shots and was clean. I apply this every month but noticed that she boggs down, goes to bed and sleeps alot and is'nt her self for about 12 to 16 hours after application. Anyone have this same issue using this product?

by: George

I had a similar issue with Chief. He was a pup at the time but had bloody stool w/ mucus and eventually just mucus.

The first time I thought it was something he ate... then it happened again.

Hopefully I will find something soon...

My Aussies
by: sherry

I am using Sentinel Spectrum but I feel the dosage is too high for my one Aussie as they give the same dosage for a dog for 51 lbs to 100 makes no sense, so that is why I would like to hear from other Aussie parents. I sent an email to Novartis asking why the same dosage, as my Vet feels it is safe & I feel it is overdosing.

by: Anonymous

My mini aussie as as well as a friend of mine's aussie are both on Sentinal and it works well for them. No Heartgard for us!

My Aussie died within 2 weeks of taking Revolution
by: Anonymous

I lost my 12 year old Aussie after using Revolution 2 years ago. He had taken Sentinel for 10 years ( only in the summers in Canada) and was fine. When production stopped one summer we switched to Revolution. I gave him 4 doses monthly and we noticed he slowed down that summer, got very hot in the heat. we just put it down to a very hot summer and his age. the next year I chose to continue with Revolution. After the first dose he slowed down, refused to walk. by day 5 he started falling over and seizuring on his walks. He continued doing this, refused eating, could not walk all within 7-9 days of his dose. after 2 weeks we had to put him down. He could not walk and his pulse was 200! His vet felt he wouold not survive this. Pfizer refused to acknowledge it was the Revolution. I would never give this product to any dog!

German Shepherd with possible mdr1
by: Anonymous

We can't use Heartguard Plus. We have been avoiding ivermectin and Revolution has been terrible for us. We suspected Frontline Plus didn't work well for fleas as we seen a bunch of hoping bugs around the house so switched everything and went with just Revolution. 5 months into Revolution we got swarmed with fleas, slashed any hope of springtails in the butt so no hope of a harmless bug to deal with. Never could see the fleas on my dog like with really bad infestations I seen in my youth with untreated outdoor cats, was never needed for those cats before but the fleas must have got immune to something there that year, but could see the damage on my dog and now have to see a vet to help with the after effects and find a new treatment. We plan on using Interceptor once we find a flea/tick treatment to try next and really hoping it works.

As a side note, is Bravecto, Advantage 2, Seresto collar, and K9 Advantix 2 safe to use for those with mdr1?

Try second opinion
by: Elizabeth R

I have an epileptic dog I refuse to put him in pentobarbital because all the side effects. He is now under the care of a holistic veterinarian he takes natural medications and Acupunture. He is doing wonderful.
About pentobarbital the veterinarian is the one that can low the dose or eliminate, pentobarbital can trigger seizures if is withdrawn suddenly.
About earthworms the holistic veterinarian recommend interceptor.
Hope this helps, good luck

by: Anonymous

Just brought my 13 week old mini Aussie girl home from the emergency vet! We had shots today and I told the vet repeatedly why I was worried about heart gaurd she said the dose was low and should be any problem at all and encouraged me to take it despite what I was told by my breeder. Trusting my vet I gave it to her in 6 minuets her eyes were swollen completely shut in 10 her snout was swollen and inflamed. It took me 28 minuets to drive to the nearest emergency vet and she looked like a basset hound her face puffy and dropping her heart rate had excelerated then dropped abnormally slow through the drive when it did she tried to lay down and go to sleep. It was the most terrifying thing I have ever experience I thought her airways we're going to get to imflained to breathe through. The emergency vet bill was 168 so not so bad but she had to get 2 shots a steroid and a benidryl shot to make it better. Hey tried to convince me at the vet to give it to my 8year old mini Aussie who's never had any heart worm medication before and I'm so glad I decided to wait or I would have had 2 very very sick inflaimed Aussies. DO NOT GIVE THEM HEART GAURD.

by: Anonymous

If your dog is 100% free of heartworm ONLY, switch to Revolution in ALL Australian Sheperds. you'll need your vet to test your dog. For approval first.) It is the only one that does not contain ivermectin and the only one safe for this breed. When I was told by the breeder about this, I researched it and all facts pointed to this breed having an allergic reaction to ivermectin and Revolution was safe. My dog has never had any bad reactions from Revolution (also no heartworm, fleas or ticks) and he actually looks forward to his topical treatment and treats after. Please be safe and don't risk anything that is NOT approved for this specific breed.

by: Anonymous

As well I am a new dog owner i have a Aussiedoodle and I did give him heartguard not knowing I freaked out he was luckily ok since he is mostly poodle I will not give him heartguard again I got some trifexis to give him soon I know a lady with a lot of aussiedoodles and she highly recommends the sentinel

Don't do Trifexis
by: Anonymous

I have seen alot of recommendations for Trifexis...it has the same ingredients as heartgard. Ivermectin. It is bad. Please do your research first.

Seizures on Sentinel
by: Kat

I have two rescue Aussies (one definitely mixed) that are both around six years old. The one that appears full blooded began having seizures two months ago. Last year I had him on Heartgard, and switched to Sentinel three months ago. My vet said that it has nothing to do with his heart-worm medication (Heartgard should have caused it not Sentinel), but that he now has epilepsy. His seizures were both once a month, however one was two weeks after his heart-worm medicine, and the other right before. He is due for another dosage, and began acting like he was going to have another seizure yesterday but did not. Does anyone think there is a link, or did he just randomly become epileptic?

Interceptor is Back
by: Jen J

I just heard today from my vet that Interceptor is back on the market (4/2016). That's their preferred heartworm medication for Aussies and is cheaper than Sentinel.

by: Vanessa

My 8 year old baby has been on Revolution her entire life. We had her tested for MDR1 at 6 weeks. She is mutant/normal. I did my research on this and found it was the best and safest. She is seen every year for checkups and she has had no issues at all.

no to heartworm meds
by: Anonymous

my 5 and 8 year old beloved aussies are healthy on a raw diet. i spray them with herbal spray against fleas and ticks. i make sure the perimeter of the yard is sprayed against mosquitoes. i will not give these drugs that are shown to be neurotoxic. i will test for heartworm and lyme. and continue to provide careful attention to supporting healthy diet and exercise.

by: James

I have been using Revolution (Selamectin) on my 1 year 8 month old Aussie for about a year. My vet recommended ivermectin which I quickly shot down. But I wanted him on some preventative because heartworm can affect the brain of this breed if infected, it's hard to cure unlike other breeds. After research I settled on Revolution but am not really pleased.

My Aussie had his first wave of seizures about 5 months ago and was prescribed 500 mg IC Levetiracetam three times a day. After all the testing and blood work we still can't figure out what's causing them. Since he began his meds he suffers two a month, always on the same day up until 3 months after his diagnosis where he suffered 4 and went back to the ER. They up'd his dosage to 1000mg three times a day and he has still been suffering 2 a month (which according to the vet, is their goal and they can do nothing more).

Because he had been on Revolution for several months before his seizures began, I have a hard time believing that's the cause. I have to schedule an MRI for the little guy and make sure he's all good before I consider hereditary epilepsy to be the answer. Anyone suffering this knows it is not easy so any recommendations would be appreciated.

I was hoping to find another heartworm preventative that allowed me to use an additional flea and tick preventative because Revolution does such a poor job in that regard. Although he has never had heartworm or fleas, he's had multiple tick borne diseases, I just can keep them off of him. Any suggestions? I've always been told not to use a tick collar or anything other than natural spray on repellents to battle ticks while on Revolution.

Thanks, James

by: cinders

I have a MDR1 Aussie and he had seizures after taking Trifexis. We put him on Sentinel and he was fine ... the first summer. This Spring we put him back on Sentinel and he went blind. He's 11 and the love of my life. I feel like a really bad mom.

Heartworm meds for mini aussies
by: Christa

I have 2 mini aussies and right from the beginning I told the vet they couldn't have anything with ivermectin in it. And she said that heartgard has such a low dose of it, that they wouldn't be affected. I refused to accept that, and didn't want to take any chances so they've been getting trifexis for a little over a year now. So far so good. But now I'm doing more research and trifexis has milbemycin oxime in it and apparently, if they have the mdr1 mutation gene, then they shouldn't take that either. Its hard to tell which websites are accredited and which are just bs. So I'm thinking of switching to sentinel. I still need to do more research and ask some vets to see what they think. I had both of my aussies tested for mdr1 and they both tested normal/mutant....which means they could be affected by certain meds. I guess my question is....are there any aussie owners that have tested their pet for mdr1 and found them to be normal/mutant carrier?? And if so, what heartworm med do you use?

Healthy without it
by: Anonymous

Our first Aussie lived to be 17 never had any heartworm or flea and tick "meds" 2nd Aussie is 11 and the picture of health. Our 4 month old puppy will not get any either. Just think, you give them flea and tick meds (poision) so that when ever a flea bites them it dies. That can not be good for your dog.

Seresto and MDR-1
by: Annie

Can a dog with MDR-1 safely wear a Seresto collar for fleas and ticks?

Heartworm meds
by: Peta

I've been using Sentinel Spectrum for 21 years on the 2 Shelties I had, and my 4 Aussies aged 16, 13, 7 and 4. Never had a problem with side effects, although I use 2 tablets cut into 4, as mine all weight 22 kgs or less. My sister's dog died from heartworm infestation, and it's not something I'd like my dogs to go through. I like that 1/2 tab once a month each treats heart and intestinal worms, and prevents fleas breeding if they pick one up and bring it home. I was looking at other options as Sentinel now so expensive, but now don't think it's worth the risk. If you're on a good thing, stick to it!

by: Anonymous

My dog is a mixed and does not look like she has Aussie in her, but she does. When I related that to my vet he immediately told me he would not put her on Heartguard. He put me on Revolution for the Heartworm and Brevecto for the ticks (not to be taken together).

Aussie meds
by: Chris


I had my first Aussie on Interceptor, but had to go to Advantage II when it went off the market. Frodo then went on Sentinel, however, the Advantage II caused him to have a false positive heartworm test until he died (he had congestive heart failure and cancer). My new dog was given Heartgard Plus, and I asked my vet about this, as I was told that Aussies cannot break down Ivermectrin. I plan to put Bono on Sentinel the first of next month--he is half Aussie, but I will not take any chances with him. Frodo lived to be 13, so I did something right!

Glad I found this thread Natural flea and tick treatment
by: Anonymous

I'm so glad I found this thread. My vet prescribed heart guard for my Aussie and he has been on it for 5 months with no issues other than he gets very run down after taking it (not like him at all). I began researching symptoms and saw the warning about shepherds... I'm calling my vet today to get interceptor. I wanted to share what has been working for us for fleas/ticks/mosquitoes... Cedarcide!! It's for people and dogs and I have used it on the whole family including our new dog with fantastic results. When we rescued Winston at 8 weeks he had fleas. We gave him frontline for two months and sterilized the house but they stayed on him. It was winter and he was 8 weeks so he wasn't getting reinfested from outside so we bathed him in the Cedarcide dog shampoo and sprayed the tick shield (more concentrated than the regular cedarcide) and the fleas disappeared! We continued the vacuuming of furniture and I bought the flea traps and nothing! It's my feeling that the cedarcide killed the fleas living on him and the spray prevented them from coming back. We use the spray all summer for mosquito repellent and it's amazing how well it works. I use the yard spray, dog shampoo and personal spray and am thrilled with the results. I'm not affiliated in any way! Just a happy customer! It's made in Texas of all natural cedar wood oils. It has a pleasant woodsy smell that I love... it's a win win!

Now if I could just get the heartworm meds worked out. Thank you for all this great information.

Interceptor - big side effects
by: Heidi B

We live in SW Florida and a lot of dogs have heart worms in our area (our vet said). So finally after one year without any chemicals, we gave our mini aussie one interceptor pill - which he didn't take well. Vomiting, diarrhea, lack of appetite. He was lethargic, didn't want to walk or play but stared into space and was restless - getting up after a few seconds, laying down, getting up, laying down... We were really worried... After three days he got back to normal... We're sooo happy!
Now our vet recommended to put him on Heartgard... because of the great risk of Heartworms we'll try it... not feeling too comfortable about it...
We do use all the natural stuff but the mosquitoes are ruthless here and we feel we don't have a choice...

by: Stevens Susan

My female mini Aussie was just prescribed ComboGuard. Does anyone have experience with this product? Its ingredients are spinosad And milbemycin oxime. She is a Year and a half old and has never been on any medication other than her vaccines. Thanks in advance. She’s a spayed female @ 30 pounds.

No to Trifexis
by: Anonymous

Our Aussie had a major seizure and bit up a family member's hand while on Trifexis. Didn't realize how hard it is to prevent heart worm in Aussies.

heartworm prevention for MDR1 dogs
by: Megan Lyden

My dog (border collie) is heterozygous for the mutation (just had her tested at WSU).

Look over the pages on WSU's website. They do not recommended the heartworm prevention drugs that combine spinosad with ivermetcin.

We use interceptor, no problems with it
by: Lisa

We use interceptor on our Aussie, they give it by the weight of the dog. It is a chewable tablet, but we have to hide it in cheese to get her to eat it. Its kind of a large pill, we just cut it into pieces. We have had no health issues do far. Hope this helps.

MDR1 positive mini Aussie
by: Sarah

I have a 28 lb mini Aussie boy who was tested MDR1 positive when we adopted him 2 years ago. He is on Interceptor and the old Advantage drops (get them from Canada or Mexico). No problems.

by: Caitlin

I have 7 mini Aussies between 8yrsold and 9weeks okd and the breeder told us of the horror stories of heartgard that unless tested for the gene mutation to stay clear of it. Up until this past year I've had all my guys on trifexis with out any side effects. Last year, with vet recommendation, we switched them and my boyfriends two Collies to Revolution and they have been great. I will not attempt heartgard on my guys, there is no point in risking it.

My dog was B grade on genetic - Revolution used
by: Melinda

My pup tested positive in DNA test for being carrier affected. We chose to go with Revolution and have had no problems (we found out that's what the breeder uses). It is important to do your own research and then talk to your vet (make sure you are informed when you speak with them and they know about MDR1 genes and drug sensitivity).

Sheltie owner
by: Anonymous

I have owned Shetland Sheepdogs, Shelties, for over 20 years. I was told by the breeder to purchase Sentinel for heartworm medication. It does not contain ivermectin. I have used it with all four of my dogs and have never had an issue.

Mini Aussie
by: Anonymous

My Vet has my 2-year-old Mini Aussie on Intercepter Plus. She does fine on this when I can finally get it down her. She hates the taste. Good luck!

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