Comparison of Heartworm Preventatives (re: Safety)

Okay, first of all, my vet, who will use Proheart if /when it comes back out did state to me that it is not as safe as the monthy pills.Second, Canada is not as sure about as safety as it was.  The below post is from Health Canada.  Take note of the new warning they require Fort Dodge (Wyeth) to put on the drug label.  From this it appears they think it should only be given to dogs that other HW perventatives can not be used on with effectivness.

An Update on the Safety Evaluation of ProHeart®6 Sustained Release Injection
February 2006
Health Canada's Veterinary Drugs Directorate (VDD) has been working with Wyeth Animal Health, the manufacturer of ProHeart®6, to investigate the safety of this product. VDD's Pharmacovigilance Unit requested data from the manufacturer regarding the safety of this product under the recommended conditions of use. VDD has received and evaluated the data and recommends:

• specific changes to the approved label of ProHeart®6, and
  
• that Wyeth Animal Health notify veterinarians of these changes.

Wyeth Animal Health has revised the label to reflect Health Canada's safety concerns. The following advisory statement has been added to the Cautions section of the label and package insert:
Because of its potential for serious adverse drug reactions and the absence of identifiable risk factors associated with those reactions, ProHeart®6 is only indicated for those dogs in which alternative preventatives cannot be effectively administered.
In addition, the label provides information for veterinarians about Canadian and international adverse drug reactions to ProHeart®6.

Wyeth Animal Health is also preparing a continuing education letter regarding the label revisions which will be distributed to veterinarians in the near future.

ProHeart®6 will, therefore, remain on the market and continue to be available to veterinarians across Canada.

***********************************************************

Okay, I don't know how it works in Europe, etc, but from Australians coming to doghealth2 to learn about ProHeart (down there it is 12 month, called ProheartSR12) we are told they can't find information about numbers of reactions, actual reactions, etc.  There they report reactions/deaths to the proper government agency, who then turns it over to Fort Dodge to investigate and rule on as to if it was ProHeart that caused the reactionand or death.  Kind of like letting the fox investigage the hen house raid.

One who from Australia who almost lost his dog to Proheart SR12 came to this board to talk about it and find information.  I am still in contact with him, his dog has never fully recovered and never will.  He got the information from our FDA site and from Fort Dodge's own site to get compensation for his dog.  His words, not mine "Dracula is in charge of the blood bank, Micheal Jackson is in charge of Kindergarden and Fort Dodge is in charge of itself and finds nothing wrong."

I know that some of the reactions/deaths reported are not related to PH6, but the FDA says only 10 to 15% of the cases are reported to start with.  However, they recieved thousands of reports and they could see patterns.  Say they got reports of 1867 dogs ages 1 to 13 going into a seizure for the first time in it's life within 12 hours of PH6, they could be pretty sure it was the PH6, if that was the only drug given.  They  354 reports of dogs coming down with AIHA within 4 weeks of getting PH (only), that it is good bet the PH6 caused it.  They get 2 reports of a dogs coming down with AIHA 5 months after PH6, it would be a far stretch the PH6 caused it...unless of course the time release didnt release over the momths  and sudden did all at once.  But no way of possibily knowing that, so those would be ruled not the fault of PH6.

Some diseases take longer to show up, like it is known AIHA takes up to 4 weeks, and possiblily longer  to set in, and then it can take from a few days to  a couple or more weeks for the symptons to really manifest enough for the owners to know something was wrong.  Had my vet not told me the day Hunter was diagnosed with AIHA that when it came time for his next PH6 injection, we wre going back on the monthly pills, i wold have never thought of the PH6 as causing the AIHA.  (This was done after we had gone over everythign the previous 2 months and Proheart6 was the only thing different.)  Liver disease usually takes longer.How many times have these not been associated with PH6 because of the time line, but actually were caused by it?

Many of us have stayed in close contact with each other via e-mail, phone  and the yahoo groups caninedrugdangers and doghealth2..  Some are very computer/search savvy and can find all kinds of  information, and I mean printed actual documents with letter heads, etc.  Some are in close contact with some in the FDA.  So far none have found any, or at least reported, any studies done to back up the safety of Proheart6.  And to be honest, I would not believe any study done by a university.  Why?  Because Fort Dodge paid me the diagnostic part of Hunter's bill ( $1049.71 of the $2300 bill), but they also made a "generous donation in Hunter's Memory" to Texas A&M Vet school/research.   There is no telling how much money they pump into these universities and I do not think for one minute that a university is going to find something against  a company like that and risk losing all that money they  receive from that company.  I also know that A&M did not answer a letter a wrote asking if they were seeing more cases of AIHA (following Proheart injections) in thier hospital.   IF they weren't, why not say so.   I had read on a vet tech board that many hospital were seeing more of it and a couple even said it was suspected Proheart6 was causing the upswing.
 
When Proheart6 first came, they said it was safe for heartworm positive dogs.  It wasn't.  The changed their label at the FDA request.  More reports of reactions were coming in  the FDA again requested a label change to include these reactions, and Fort Dodge did admit "unforeseen reactions were occuring"".  The day my Hunter got his fatal injection, death was included in the new label.
 
Many of us are under the impression that the FDA's "request" to pull it was much like the way the army gets  "volunteers to to do a job."  You are not ordered, but you best volunteer.

Let me clarify a few things: First off, Proheart was not " pulled from the market...by the FDA". As a matter of fact, in 2004 it was voluntarily withdrawn by the manufacturer on request by the FDA, which makes for a huge difference in legal and practical matters. Secondly, since that time there has been a thorough reevaluation of the drug, and it is deemed safe (as safe or safer as other products) by the vast majority of researchers in the field. The most comprehensive study (by L. Glickman/Purdue) could not find any increased risk when compared to two other major brands of heartworm preventatives. Many reports of Proheart6 related problems, for instance, could in no way be shown to be related to that medication. What seems to have happened, for instance, was that once the snowball got rolling, every conceivable problem that occured with a dog within a week or two of administering that medication, suddenly was thought and reported as possibly linked to it. Using that procedure, drinking water will seem dangerous. Third, proheart remains available - to the best of my knowledge - in every other country it had been available before, simply because there is no scientific evidence of any increased risk when compared to dogs taking 6 pill of another product versus the one proheart shot (actually, it is still widely used in livestock even within the US). That the FDA approves or disapproves of a medication has many reasons, some political, some legal, some scientific, and when compared to drug agencies of other first world western countries, it has one of the worst reputations regarding product safety evaluation - not by my estimation, but that of JAMA (again, for a multitude of reasons) - but that will take us way too far off course for this thread here.

Hopefully I can clarify some of this information for everyone.  I see your occupation is of a 'Parasitologist' so wanted to make sure you had accurate information. 
1.  You are correct, PH6 was not "pulled from the market by the FDA" BUT they did request it.  The manufacturer admitted they did do it voluntarily due to that.
2.  There has NOT been a re-evaluation in the USA regarding safety; the information you refer to done by Larry Glickman at Purdue was presented at the VMAC meeting 1/31/05 and the information he studied was taken from Banfield records (because of their computer program for all locations) and was for cases thru July or August of 2004 (before the recall).
3.  At this time it is available in other countries (Europe and Canada.  Australia has a 12 month verison). 
 
It is intersting to find that Canada did a re-evaluation upon the recall in the USA.  They  have recently re-approved the product but with some changes.
[linkhttp://www.hc-sc.gc.ca/dhp-mps/vet/advers-react-neg/proheart6_update-mise_a_jour_e.html]http://www.hc-sc.gc.ca/dhp-mps/vet/advers-react-neg/proheart6_update-mise_a_jour_e.html[/link] and you can read the letter sent to vets in Canada at [linkhttp://www.wyethah.ca/pdfs/Canine/EngLetterMarch16.pdf]http://www.wyethah.ca/pdfs/Canine/EngLetterMarch16.pdf[/link] 
 
According to this the label now includes a 'boxed warning':"BECAUSE OF ITS POTENTIAL FOR SERIOUS ADVERSE DRUG REACTIONS AND THE ABSENCE OF IDENTIFIABLE RISK FACTORS ASSOCIATED WITH THOSE REACTIONS, PROHEART 6 IS ONLY INDICATED FOR THOSE DOGS IN WHICH ALTERNATIVE PREVENTATIVES CANNOT BE EFFECTIVELY ADMINISTERED.*" The entire transcript of the VMAC meeting (where Dr. Glickman first presented the same information) can be found at [linkhttp://www.fda.gov/cvm/Documents/VMACWinter05Trans.pdf]http://www.fda.gov/cvm/Documents/VMACWinter05Trans.pdf[/link] For those with other heartworm preventative concerns, you will probably be interested in reading what was presented at the Heartworm Society Convention in 2004 [linkhttp://www.dogsadversereactions.com/moxidectin/heartwormconcerns.html]http://www.dogsadversereactions.com/moxidectin/heartwormconcerns.html[/link] I hope this information clears some misconceptions []

Sandra, it may be me that you are referring to when you mentioned that someone here gets HW check every 6 months and does not give HW pills.  That would be for Ollie, as he is the one that had allergies and skin problems, he now gets nothing. 

I do give Bubblegum Interceptor, it was found that it caused the least problems for Great Danes.   That being said, I think everyday about it, and leaning very close to also testing her twice a year. There is no way in the world that I like putting pesticides in my dog once a month. I think if I lived down south where the weather is warm all year around, and mosquitos thrive, I might think differently. But here in the cold states having a dog that is not out all that much, I just have a really hard time with it.  My vet uses Sentenel because it controls fleas..Bubblegum doesn't have fleas, I've NEVER had a dog with fleas, so why would I want to kill fleas? We used Revolution on Ollie one year, you should have seen what it did to his skin where it was applied,,same with Sadie the Dane down the street last year.
You know, we talk a lot about cancer and liver problems in dogs and we relate it to the food they eat and vaccinations and all, I have to think that giving them pesticides month after month for their whole lives takes a heavy toll on their body, how can it not?

As far as PH6, the sheet that I have printed out in front of me (which could be out dated) has 599  reported deaths since being put on the market in June of 2001.  How can that not be more dangerous than Interceptor that has 127 reported deaths since 1992?

I also question the recall of  PH6 by the FDA!   I would like to know if the FDA let them "save face" by volunteering to recall, and if they would not have volunteered would the FDA have removed it themselves??? Somehow I believe they would have.  Never underestimate the power of the drug companies.  The mere fact that in Canada where they changed the packaging to read that it is not recommened except where alternative methods can not be effectively administered means to me that there are some very very serious problems with that drug in Canada also. Don't you wonder if the other countries had something like our FDA that we might hear even more about the drug?

Two years ago, when I took Ollie for a HW check, to my little country vet that I used to go to before I got Bubby (she really doesn't like to take care of the big dogs, so I just thought I would save myself a lot of problems by finding a different clinic for her) and I figured that she would try to talk me into getting him HW pills and boo-boo me for not, but instead she said HW was easily treated now a days when caught early enough.   It sure makes me think that I just might want to get those blood tests often enough to catch any problem early, intead of pumping her full of pesticides each month when she may never see a heartworm.

Wasn't me that memtioned not giving pills but getting tested every 6 months.  I know Ollie had so many problems and you were terrifed of putting anything on or in him for fear of reaction and that have always believed he very well could have been on the DIED column had he gotten PH6.  And since kayCee had a reaction to her 2ed set of annuals. I know EXACTLY where you ar coming from with reluctance to give HW pills, etc.  If i could get by with it, she would only get the pills part of the year.  Every time I put anything on or in her, i worry because of that one reaction, probably to lepto.
 
No, wasn't me who said anything about not giving pills year around.  You are doing excatly the right thing for you situation.

OOPS,,,that would be Cathy!  Sorry!

No sweat.      By the way, been meaning to tell you I love your avatar, looks like Bubby is using the computer, so cute.

Thanks Sandra,,, a couple of weeks ago someone mentioned it (they had just noticed it) and I posted my "other choice!"

Thanks Dyan - As soon as I saw your post, I remembered it was you that did the HW testing vs. preventatives.  As you know, Sassy has been having so many allergy (?) problems.  After 10 days of using the topical Baytril, the tummy area isn't any better and maybe a tiny bit worse.  So - I just can't bring myself to put that Revolution on her or even think about giving her the pills.  I'll have to see, but I may just NOT do it and ask the vet to test her mid-summer and then early to mid-fall.  I know she won't like the idea, but hopefully she'll understand.

When you have a dog that has allergies or health problems it is a nightmare trying to decide vax or no vax, heartworm pills or no heartworm pills, this food or that food, etc, etc.  I learned from Hunter's death that if something is working for you dogs, don't change for something that is suppose to be better.  Better for one dog is not better for all.  I did and lost my precious boy.  Never again.

I know what you mean Cathy. 
Here is a link I had saved,,,kind of makes you feel a little less nervous about what to do. [linkhttp://www.preciouspets.org/newsletters/articles/heartworm-article.htm]http://www.preciouspets.org/newsletters/articles/heartworm-article.htm[/link]

Thanks Dyan - that is an interesting article.  Like you, we never ever have a problem with fleas with any of our pets, so that's at least one thing I can be thankful for.

Hello laurryn []

I am not quite sure what you felt was in need of a clarification. You agree with two of my points outright, and essentially quibble over the wording of the second item. In science, research that is going over the collective data of past trials is called a meta-study, and its results are deemed more reliable than any individual study, simply as it takes care of some of the problems single studies - no matter how large or well-controlled they are - might have. Glickman did one of these meta-studies (involving a huge number of cases), and that of course constitutes a re-evaluation of its safety by this research group. There have been no major studies, to date, that opposed his findings (to the best of my knowledge).

Also, "evaluations" are no national matter. To say that " There has NOT been a re-evaluation in the USA regarding safety" simply makes no sense, other than political (remember, the drug is not forbidden in the US). If qualified research groups in Great Britain, Australia and France show that drug ABX is safe or not safe, then it is also safe or not safe in the USA, regardless of what the FDA decides. FDA decissions are not merely bound by safety concerns, but also by political questions and leanings (there are quite a number of drugs that are legal in the US, but close to nowhere else, and vice versa, often for differences in morality or financial backings, ie lobbying). If a Danish research group can show that it can split the atom, and a Swiss group confirms this, then the same science will also apply for the US.


Sandra: It is correct that in some countries proheart is now sold with new warning labels (mostly, mind you, for legal reasons, not scientific ones). What is not correct, however, and what one sees all too often across the internet really, is the exagerated claim that there is now "the new warning they require Fort Dodge (Wyeth) to put on the drug label". As you so nicely quote below that yourself, this new warning was just "recommended", not "required". A big difference, reflecting the lack of any evidence of the harmful character of the drug. I find it (in a nice way!!) amusing btw that you overstate the issue in precisely the same manner as minimon did, which was the entire cause for that previous post of mine. []

Anyhow, don't put me in a corner here. I did not mean to defend proheart or any other drug specifically, but simply meant to say that what a competent vet prescribes for your pet will normally be alright. For those in the US, that will not include proheart anyhow. Furthermore, as a reaction to some input we received here, I wanted to encourage to use less hyperbole and more accuracy in promulgating claims about the benefits or downsides of a medication, food, or whatnot.

I think thats all for me on that point. []

 

As you so nicely quote below that yourself, this new warning was just "recommended", not "required". A big difference, reflecting the lack of any evidence of the harmful character of the drug.

 
The fact that it was changed to add this to the package, means a lot to me.  They try to make it sound as safe as possible, but when they have to change it after the drug as been out for some time, just means that problems developed.  In the US, I believe the package was changed a couple of times and Dear Dr. letters were put out, and then it got recalled! They certainly didn't do all that for the good of the company. They did it either because they had to (perhaps because FDA told them to), or to cover their butts.
 

but simply meant to say that what a competent vet prescribes for your pet will normally be alright

While I hope this to be true, I'm not sure.   Are vets still prescribing yearly vaccinations after all the veterinarian schools changed their protocols? Yes, maybe not all, but most are still doing them yearly. At least in my neck of the woods.  And at the risk of causing problems from them.  Could it be because the drug companies are always visiting them, giving them things?   Geez, I hope not, but have to wonder.      

ORIGINAL: polymatheia

Hello Mini-Mom

Let me clarify a few things: First off, Proheart was not " pulled from the market...by the FDA".

I believe you meant to be addressing minimon....no hyphen. I just wanted to "clarify" that for YOU. [sm=wink.gif]

Amelia, yep that was me he was addressing...similar user names, both have Miniature Schnauzers and both have dogs named Bailey!  lol