Natalya,

You might want to do more research on HW preventatives. they do not cover a dog for 45 days. They spike in the first 4 days then the dose is so low the dog can get infected on day 5-7 then when the HW preventative is administered again at the scheduled time(30 days) it reaches back to kill the new infestation.(quote from a rep). The only HW meds shown and claims to last the full 30 days is Advantage Multi.

 Quote: anne jones

what is the reason that you are HW treating 2x a month rather than the usual 1x?

I should have posted the standard disclaimer; I am not giving veterinarian advice. I'm only posting what has been recommended to us to combat a serious problem.

To clarify, we give each dog, West of the TN River, HW preventative twice a month. The first one is Heartguard, then on the 15th of the month, the dog gets Advantage Multi. One preventative didn't seem to be more effective than the other. We do the twice monthly because it was recommended to us by competent medical practioners. It is experimental and only used in the aforementioned areas. They (medical professionals, drug sales folks) don't know why a large number of dogs in that area test positive, only that they do. One brand of HW preventative does not seem to be more effective than others.

As with everyone else, HW is a serious problem that can, in most cases be prevented. Removing a dog from service has serious consequences far beyond the cost of treatment. So far (knock on wood) the twice a month treatment has prevented any other dogs from contracting HW. None of the dogs in our "fleet" have contracted heartworm in other parts of the state.

DFrost

 Quote: Lorelei Sims

Natalya,

You might want to do more research on HW preventatives. they do not cover a dog for 45 days. They spike in the first 4 days then the dose is so low the dog can get infected on day 5-7 then when the HW preventative is administered again at the scheduled time(30 days) it reaches back to kill the new infestation.(quote from a rep). The only HW meds shown and claims to last the full 30 days is Advantage Multi.

Lorelei, first of all, I'm so sorry to read about you dog. I hope his treatment goes smoothly.

Do you have a source for the research you are quoting, or was it only from the rep? I would like to read it if you have any idea where it came from.

 Quote: Lorelei Sims

Natalya,

You might want to do more research on HW preventatives. they do not cover a dog for 45 days. They spike in the first 4 days then the dose is so low the dog can get infected on day 5-7 then when the HW preventative is administered again at the scheduled time(30 days) it reaches back to kill the new infestation.(quote from a rep). The only HW meds shown and claims to last the full 30 days is Advantage Multi.

Lorelei, here's a sampling of where my info came from (re the latter 2 links: I regard Dr. Dodds' opinion as one of the most credible out there):
http://leerburg.com/forums/ubbthreads.php/ubb/showflat/Number/178037/page/0/fpart/1

http://www.tibetanmastiff.net/Heartworm.html

http://www.katberard.com/hea_parasites.htm

In either case, it doesn't sound like that was what David was referring to - since there is obviously a very serious/mysterious epidemic of cases in the mentioned areas (in treated dogs), he's taking special precautions that would be unnecessary for most people. Though if what's happening in the south is just the start of a heartworm strain that's immune to Ivermectin, then perhaps we'll ALL need to radically change our treatment types and intervals...

Wishing your dog the fastest recovery,
~Natalya

 Quote: natalya zahn

... In either case, it doesn't sound like that was what David was referring to - since there is obviously a very serious/mysterious epidemic of cases in the mentioned areas (in treated dogs), he's taking special precautions that would be unnecessary for most people. Though if what's happening in the south is just the start of a heartworm strain that's immune to Ivermectin, then perhaps we'll ALL need to radically change our treatment types and intervals...

Wishing your dog the fastest recovery,
~Natalya

Ditto on this not really being what is under discussion here, but Natalya is correct that many authoritative sources, including the FDA, have stated (right or wrong) that HW "prevention" meds (not actual prevention as much as killing immature infestations) were not strictly necessary on a 30-day protocol: "The FDA approvals cite studies showing that Heartgard, Interceptor and Revolution provide protection beyond 30 days. If you are very good about remembering to give medications, and you can watch your dog after administering the pill to be sure that it is not spit out or later vomited, it may be safe to use heartworm preventatives less frequently than every 30 days. Dosing your dog every 45 days is a conservative way to stretch your dog's dosage schedule.

The original FDA approval for Heartgard states, “The target dose of 6 mcg per kilogram of bodyweight was selected from titration study 10855 as the lowest dose providing 100% protection when the dosing interval was extended to 60 days to simulate a missed-dose circumstance.”

The drug manufacturers’ pre-approval tests indicate that even longer dosing schedules may convey protection from heartworm – but I wouldn’t stake my dogs’ well-being on dosage schedules extending beyond a somewhat arbitrary 45 days. ..... It is important to realize that, if you do decide to modify the way these medications are given -- by splitting pills, giving pills less often than monthly, or using reduced dosages -- the guarantees provided by the manufacturers will be invalidated. ”
from http://www.dogaware.com/articles/wdjheartwormprevention.html (Whole Dog Journal)

BUT http://www.yourpetsbestfriend.com/your_pets_best_friend/2009/05/are-heartworms-getting-worse-a-seminar-part-3-of-6.html

Back to the O.P.: Your dog and you are in my thoughts and heart. I want to say that after Katrina, I was involved with fund-raising and procurement of treatment for some of the many many resultant HW-positive dogs, and I can tell you that the success rate among the dogs diagnosed early and treated was very good.

The material I am quoting is from the Bayer reps/ Advantage multi and the material my vet gave me from them. One of the reasons vets push Advantage Multi now is that it states it stays constant in the bloodstream for the full 30 days as opposed to the others.
Will see if I can scan in the material.
I live in the hot spot for HW so I will beef up my preventative after we finish out treatments. I have planned to start the injections at the start of Nov so I can take off the necessary time for him.
Hoping all goes well. Thank all of you for your feedback.

Connie, others, here are the sites I was given by my vet to do research on. One is the American Heartworm Society and the other is the Westwood Animal Clinic site. I have read others stating the same thing though.

Link from the Westwood Animal Clinic on Heartworm preventatives.
http://westwoodanimalhospital.com/MedPages/Parasites/Heartworm%20%20-%20Canine%20Heartworm%20FAQ.htm

This is from the American Heartworm Society that my vet sent me to to read.
There many types of medications available for heartworm prevention. What is the difference between the daily and monthly tablets?
ANSWER Until the late 1980s, the only medication available for the prevention of heartworms had to be given daily. These products work by killing the microscopic heartworm larvae deposited by the mosquito, but must be given every single day to be most effective. This is because infective heartworm larvae quickly molt within two to three days into their fourth stage of development. This fourth stage can not be killed by the daily medication. Daily heartworm preventives have largely been replaced by monthly products and are no longer commercially available in the United States. Compounding pharmacies still formulate daily preventives on an "as needed" basis. An important note to keep in mind is that monthly medications are quickly eliminated from a pet's system and do not continue to work for 30 days. Instead they work "backwards" to eliminate the larvae the pet acquired the previous 30 days, in essence, "de-heartworming" our pets each month in many cases, these monthly preventives control other parasites too.

Here is the summary from the 2010 American Heartworm Society Symposium

Another theroy floated by a research chemist on another forum I'm on is that minimum effective dose is no longer valid in regions with a heavy mosquito carrier rate.

I hope everything goes smooth in your dog's treatment and recovery, Lorelei! About 5 years ago my boss adopted a HW+ dog. The dog came through HW treatment just fine and has never had any health issues because of it.