Heartworm Medication

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yummybagel
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Heartworm Medication

Post by yummybagel » Wed Jul 25, 2012 1:19 am

Hello! I was just wondering if anyone knew of a good heartworm medication that I can get in the USA? I am changing vets, and wanted to change the heartworm medicine as well. I've been giving him Wormshield, which I have been getting from my vet. Are there any precautions that I should take before changing it?

Also, are there any recommendations for ear cleaning solutions? I have a Beagle, so I need to clean his ears quite regularly.

rnor1120
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Re: Heartworm Medication

Post by rnor1120 » Wed Jul 25, 2012 11:55 am

Hi there!

Is there any particular reason you're switching meds? If there's no real reason to switch, I probably wouldn't. But if you are going to switch up drugs, it would be a good idea to have a heartworm SNAP test done first if your dog hasn't had one recently (within the past 6 months).

If you're just looking for a different brand, Iverhart has the same ingredients (Ivermectin/pyrantel) that Wormshield does (and these drugs cover heartworm, roundworm, and hookworm). If you're looking for a different drug completely, the main ingredient in Revolution, selamectin, is in the same drug family (macrocyclic lactones). Revolution covers heartworm, fleas, ticks, sarcoptic mange mites, and ear mites, but not gastrointestinal parasites (roundworms, hookworms, whipworms). I personally use Advantage Multi (moxidectin/imidacloprid). That covers heartworm, fleas, and gastrointestinal parasites (but not ticks) and it's a topical spot on so it's easy to give. Sentinel (milbemycin oxime and lufeneron) is another good one - this one covers heartworm, fleas, and gastrointestinal parasites, but not ticks.

Since most of these don't cover ticks, it would be a good idea to add in a good ectoparasite control (if you don't already have one). I used Frontline (fipronil) in the past and liked it quite a bit.

This is all good stuff to bring up with your vet. You can make a list of these things and have him/her make a recommendation based on the parasites most commonly found in your area.

lucyandbella
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Re: Heartworm Medication

Post by lucyandbella » Wed Jul 25, 2012 12:41 pm

If you want one without ivermectin, I use Interceptor. It is not a flea repellent; it just protects against heartworm and is also a general de-wormer. If you want to stick with the same ingredients you had I have also heard of Heartguard which has the ivermectin. Both of these are chewable tablets.

yummybagel
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Re: Heartworm Medication

Post by yummybagel » Wed Jul 25, 2012 6:44 pm

Thank you!
Can I ask what SNAP test is? I don't think he had it at all in the past...

And also, the reason I wanted to switch was because I heard someone say that Ivermectin is not very safe. She claimed that her puppy died because of Wormshield, and that Ivermectin was what caused his death. Since my Beagle doesn't seem to have any problem, maybe I should just stick with it.

lucyandbella
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Re: Heartworm Medication

Post by lucyandbella » Wed Jul 25, 2012 7:18 pm

Studies suggest ivermectin (and some other drugs) is toxic to herding breeds and some sight hounds because they can carry a gene called MDR1. That is why my two herding dogs are on Interceptor. Ivermectin has killed some of these dogs, what happens is the drug goes to their brain and is not transported out like in normal dogs. This causes nervous system problems and can cause death though some have survived with treatment. As far as I know as long as your dog isn't a herding breed and you are dosing properly then ivermectin is fine, also not all herding dogs have the gene and they can be tested for it.

SNAP test is how heartworm is tested; you probably had your dog’s blood drawn to check for heartworm before he stared medication. The vet then uses the SNAP test to see if the blood sample is positive or negative for heartworm.

ClareMarsh
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Re: Heartworm Medication

Post by ClareMarsh » Thu Jul 26, 2012 8:04 am

For ear cleaning I use Almond Oil, pop a little in the ear, rub the ear, let dog shake nastiness out then wipe residue with a cotton wool pad. Bit greasy and messy but all natural :D
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rnor1120
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Re: Heartworm Medication

Post by rnor1120 » Thu Jul 26, 2012 5:47 pm

SNAP test is the antigen test for heartworm. If your vet put your pup on a heartworm preventative, s/he should have drawn some blood and tested it first. The nice thing about SNAP tests is that they also test for Lyme, Anaplasma, and Ehrlichia. Depending on your region, it's recommended to retest your dog every 1-3 years (every 6-12 months where I am :shock: ). There are other ways to test for heartworm (IE drawing blood and sending it out to a lab), but the SNAP is the one most commonly used because it's cheapest and it can be done in-house.

The dogs that are sensitive to Ivermectin are collies and collie mixes - they lack the gene for the enzyme that transports the drug out of their brain once it's crossed into it. Beagles are not sensitive to ivermectin, and any sensitivity would have become apparent after the first dose or two.

Ari_RR
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Re: Heartworm Medication

Post by Ari_RR » Thu Jul 26, 2012 6:07 pm

We use heartgard and frontline.
Which I believe are not the strongest ones out there for the job they are supposed to.
However, the stronger the medicine, the worse are potential side effects.

But also, we consider the dog as well as the environment..
For example - last year tick situation was horrible, so we used frontline every month.
This season is infinitely better tick-wise.. And with a light colored, short hair dog like ours it's fairly easy to spot ticks, so we check him carefully after walks but stopped applying frontline.

yummybagel
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Re: Heartworm Medication

Post by yummybagel » Mon Jul 30, 2012 1:22 am

ooo I see. Then I do believe he did get SNAP. Though they never mentioned it as SNAP. They always say that they tested for hearworm and that's it.
rnor1120 wrote:The dogs that are sensitive to Ivermectin are collies and collie mixes - they lack the gene for the enzyme that transports the drug out of their brain once it's crossed into it. Beagles are not sensitive to ivermectin, and any sensitivity would have become apparent after the first dose or two.
Phew! That's a relief. Then I will keep him on Wormshield. :) I guess I should be asking my vet this, but if my dog is 25 or 30lbs, then I'm not sure how much I should dose him. Because for Wormshield, there is one for up to 25lbs and another one for from 30 to 50lbs. I fear that if I use the up to 25lbs one, it might not be effective, but if I use the 30 to 50lbs one, then I might be overdosing him. He is 30lbs now, but I plan to put him on a diet and try to lose 5lbs so that his weight can go down to 25.
ClareMarsh wrote:For ear cleaning I use Almond Oil, pop a little in the ear, rub the ear, let dog shake nastiness out then wipe residue with a cotton wool pad. Bit greasy and messy but all natural :D
Almond oil?? Haven't heard of that before. Is it just normal oil like olive oil?? I should definitely look that up. Thank you for that!

rnor1120
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Re: Heartworm Medication

Post by rnor1120 » Mon Jul 30, 2012 7:26 pm

yummybagel wrote:I fear that if I use the up to 25lbs one, it might not be effective, but if I use the 30 to 50lbs one, then I might be overdosing him. He is 30lbs now, but I plan to put him on a diet and try to lose 5lbs so that his weight can go down to 25.
Have a chat with your vet. The nice thing about these heartworm drugs is that it's REALLY hard to overdose them unless, for example, you're dosing a collie with ivermectin. If you're really worried, you can always opt to purchase the drug on a month-by-month basis instead of buying a 6-month or 1-year supply. That way, you can weigh him monthly and get the most correct dose. And it will help you keep track of his weight loss progress :D .

yummybagel
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Re: Heartworm Medication

Post by yummybagel » Tue Aug 28, 2012 1:14 am

So I visited my vet's office to get the heartworm tablets. But they told me they can't give me the whole packet because he is due for another hearworm test in September. When I checked his medical records, he got his hearworm test in March. Is it really necessary to get a heartworm test every six months? I know someone told me that it is probably a good idea if I'm changing meds, but if I'm staying with the same meds, is it necessary?

Also, he is due for a whole bunch of vaccines. Just wanted to ask what people in this forum do for vaccines. I've heard that over vaccinating your dog isn't good.

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Sabrina
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Re: Heartworm Medication

Post by Sabrina » Tue Aug 28, 2012 11:31 am

Also, he is due for a whole bunch of vaccines. Just wanted to ask what people in this forum do for vaccines. I've heard that over vaccinating your dog isn't good.
Check out this thread: viewtopic.php?f=11&t=15318 It started out as a spay/neuter question, but then people added in what they do about vaccinations. I found it really helpful - I didn't know that you could do titer blood checks to see if the last vaccination is still effective, so that's what I'll be asking for next check up. (Except for the rabies vacc, which is required by law in my state every year.)

rnor1120
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Re: Heartworm Medication

Post by rnor1120 » Sun Sep 02, 2012 7:04 pm

yummybagel wrote:I know someone told me that it is probably a good idea if I'm changing meds, but if I'm staying with the same meds, is it necessary?
Depends on the area. If you're in an area that is rampant with heartworm (IE the southeastern US), then 6-12 months is the recommendation. Otherwise, it's usually recommended annually. The vet may not be aware that your dog's been tested within the year (if my memory serves me correctly you've just switched vets?) and you can always present them with proof of your last test.
yummybagel wrote:Also, he is due for a whole bunch of vaccines. Just wanted to ask what people in this forum do for vaccines. I've heard that over vaccinating your dog isn't good.
Some vets still recommend annual vaccinations (which is fine), but the current AAHA (American Animal Hospital Association) guidelines suggest every three years. Annually will not harm your dog. You can always request titers instead of vaccines if you're still worried, but the caveat there would be the fact that almost all vaccines come as combos. So if the vaccine comes in a combo as ABCD, and your dog has adequate titers for A, B, and D but not C, you can't just have a vaccine for C. And if your in a Lepto hotspot, that vaccine is every 6 months. And rabies, after the puppy jab and 1 year booster, is required by law every 3 years.

yummybagel
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Re: Heartworm Medication

Post by yummybagel » Tue Oct 02, 2012 12:03 am

I am very paranoid about heartworms, so a quick question. Does anyone ever skip heartworm prevention?

Bagel used to be on Wormshield which is a tablet, but the new vet gives out Revolution. The thing is I just put him on flea medication, and the receptionist told me that since Southern California has very very low occurences of heartworm, monthly prevention is not necessary. So I skipped the meds for this month but I'm a tiny bit worried. Just a tiny bit. :wink:

rnor1120
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Re: Heartworm Medication

Post by rnor1120 » Fri Oct 05, 2012 11:57 am

No offense to the receptionist, but she's not entirely correct. You have absolutely every right to be paranoid about heartworms, it's a really, really unpleasant disease!

The drugs work based on the parasite's lifecycle. I'll try and describe it a little to make it make sense:

A mosquito bites dog and injects larvae under the dog's skin. For about 30 days, the heartworm larvae hang out in the tissues under the skin. After 30 days, they mature, migrate through the blood, and set up shop in the pulmonary artery (the artery that goes from the heart to the lungs). That happens over a period of about 3 months. At about 6 months post-mosquito bite, you have an infection in which mature females release larvae. A mosquito bites the dog, picks up the larvae, and bites another dog. And the cycle starts over.

The drugs we give our dogs are designed to kill the heartworm larvae that are under the skin. Once they leave the skin, they are too mature to be sensitive to the preventative dose. Since they only live under the skin for 30 days (and hence are sensitive to the drugs for only 30 days), we dose our dogs monthly. Dosing every 60 or 90 days instead of 30 really offers no protection and will allow any larvae under the skin longer than 30 days to mature and potentially set up an infection. Does that make sense? Basically, we dose our dogs monthly to nuke anything they may have acquired over the past 30 days. The longer you wait between doses, the greater the chance you take in allowing a heartworm infection.

One other downside to infrequent dosing is drug resistance. By dosing infrequently, you're exposing parasites that are too strong to die to a medication. In turn, they will amp up their response to the medication and pass this on to their offspring.

Now, that being said, depending on the mosquito season where you live, you may be able to get away with seasonal dosing - if you time it right. You can only have heartworms if you have mosquitos to transmit it. Mosquitos can't survive in temperatures less than about 57 degrees F. I'm not familiar with SoCal's mosquitos, but in my home state of Ohio, you can stop preventatives after the first frost and pick it up again before Spring. So if you have mosquitos year round, this isn't a good idea.

My thoughts - as much as it sucks to buy the drugs and dose our dogs monthly, it will cost far more (money-wise and otherwise) if they become infected. Even if infections are rare in your area, it can still happen. Preventatives maybe cost $200-$300 per year, whereas the treatment for heartworm can easily cost two or three times that. Plus, to kill the heartworms you quite literally almost have to kill the dog as well. The current recommended treatment is a drug called, "Immiticide." It's incredibly painful and irritating to the muscles in which it's injected and the dog has to receive local anesthesia. Immiticide kills the worms very well, but because the worms live in the lungs (heartworm really is a misnomer...), they cause a HUGE inflammatory reaction in the lungs when they die and your dog has to remain under STRICT cage rest for a period of about 4-6 weeks while the dead worms clear the system. I'm talking in a cage 24 hours/day except to pee. They feel miserable, can't breathe well, can't leave their cage, have to be supervised in case they have a respiratory crisis... You get the idea. The chances are probably slim if heartworm isn't common in your area, but it's not really worth the risk, in my opinion.

Oh, and missing your dose this month by a few days or a week (or even a month) is not going to result in anything serious. I would strongly recommend monthly dosing though. I really hope I didn't scare you into thinking that your dog IS MOST DEFINITELY GOING TO GET HEARTWORMS, because most of the preventatives have a little "gimme" time just in case you forget and remember a week later. Your dog is fine :D . It is a little disturbing though that this advice came from the vet clinic, because chances are the receptionist has told other people this as well. I would ask your vet about this. Really double check and see if the opinions of the receptionist are the opinions of the clinic as a whole. I'm currently in vet school and that is NOT the current train of thought according to the board-certified veterinary cardiologist that taught the course.

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