I did some looking around and found some more info that MAY be helpful to you. There is a 'slow kill' method of treatment that is being used by some rescue groups and vets. It involves simply keeping your dog on heartworm preventative (ivermectin) to keep the dog clear of the microfiliae so that they can't grow into mature heartworms. This also keeps the dog from being able to infect other dogs with heartworm. It DOES NOT kill the adult heartworms but does render them sterile and shortens their life span (I misspoke earlier when I stated that heartworms don't multiply in a dog's system). This prevents the massive kill-off of worms that the traditional treatment (immiticide) causes. The danger with the immiticide is the dying worms clogging up heart valves and the lungs. The slow kill method kills them off at a rate so that the dog's system can clear the dead worms more safely. With the slow kill method, the dog will test positive for heartworms (adult) for about 2 years but will be clear of the microfilae and will not become more infested and will not be able to infest other dogs. Since you've had your dog for a year and have had him on Interceptor the whole time, your dog may be clear of microfilae (immature worms) but be positive for adult worms. If he is showing no signs of distress, you may want to consider the slow kill method. Even if he is heavily infested, some vets use a few doses of ivermectin (as in Heartguard or Revolution) to clear the dog of the immature worms before starting the immiticide treatment. You can try googling 'use of ivermectin in heartworm positive dogs' to pull up some of the info. I hope this is helpful to you in going forward, regardless of the treatment you opt for. Best of luck to you and Cooper.

I'm sorry to hear about your baby :(
Our Chloe who passed away at the age of 16, in 2005 was positive for HW's. We chose to keep her on prevention and not do the treatment. The difference is, she was about 10 when she was dx and she was at a low level, meaning she had hardly any HW's.
I had heard horror stories about the old method of HW treatment, but I've heard now that the treatment is much milder.

When this happened to Chloe, we took her to another vet for a second opinion. Our vet wanted to do the treatment and the second vet suggested we just keep her on prevention.

I know you have a lot to think about. I wish you much luck and please keep us posted.

:hug:

I'm so sorry to hear this. It's a scarey thing to have to deal with. I'll keep Cooper in my prayers for a complete recovery - even if it takes awhile. Altho I don't know anything about the treatments, the slow kill method makes alot of sense. Trust your heart to make the right decision. Hugs to all.

Heartworm treatment
 

It is true that most vets are now recommending two months of Heartgard prior to starting treatment; but, the active ingredient in Revolution is not Ivermectin.
Just wanted to FYI this one!
The basic information is correct and is a better way of treating in my opinion.

I am so sorry to hear about Cooper's condition. I am praying for his strong recovery. He is lucky to have you as his family now! :angel:

Thanks for the correction. The active ingredient in Revolution is selamectin, which I believe is a 'cousin' of ivermectin that has other agents bonded to it to kill fleas, ticks and mites. My bad....:D but here is some info on it......"Selamectin-based Products:
Revolution® made by Pfizer

Ivermectin’s entrance onto the anti-parasite warfront represented a culmination in the trend for broader and broader spectrum parasite control. Selamectin is a closely related cousin of ivermectin. It is designed for broad coverage of small animal parasites and will protect dogs not only against heartworm but also against ear mites, sarcoptic mange mites, ticks, and fleas. Cats are protected against heartworm, fleas, ear mites, roundworms, and hookworms. The product is topical, applied monthly and is fully approved for safe use in heartworm infected animals. Selamectin is not as effective at clearing microfilariae as other products and thus is not generally used in the treatment of active heartworm infections". The information is from this site..Preventing Heartworm Infection in Dogs (Chemoprophylaxis) - VeterinaryPartner.com - a VIN company!