First, yes, it does happen and it's not in any way your fault! And you haven't hurt her a bit by giving her meds during this time. Most likely she had larvae at the time of the test which developed into a few adults in between test and the next meds. It happens to many rescues and there's not a darn thing you can really do about it. Actually, it happens to the best owner sometimes when a dog upchucks a med dose, or they forget a month.
I have a dog that is allergic to Interceptor (guess who? You got it! Ben!) and I didn't realize for about nine months that he was barfing up the pills behind the couch. I moved the couch to clean one day, and realized what Ben had been doing back there. [
] Boy was I sweating the next day at the vet - actually I was almost crying.
He was negative but that was when the vet explained about the life cycle of the parasite and why it would have been fine - at the worst he would have had three months worth of mature worms and that wouldn't have been enough to warrant full treatment. We did test again six months later, and six months after that - and he started on monthly Ivomec. He's allergic to the Hartguard pills, too (go figure) - it's what they put into them though, not the ivermectin. What a mess. I've got another that's allergic to Interceptor so everyone is on good ol' Ivomec. It's cheaper anyway. [
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Here's what will happen. The next step is to determine the extent of the infection. If it's just a few adults, your vet may simply make you lay your hand on a sacred text and swear to keep up monthly treatment (with ivermectin - Hartguard) until she tests negative. This may take six months to two years. The monthly treatment will kill the babies the adults have, and just a few adults won't harm her.
If for some reason she has a more extensive infection, the vet may still suggest the above treatment if there is no evidence of damage to her heart or other organs. The vet will determine this with blood tests, a chest xray, and possibly an ultrasound evaluation. This is where the cash starts flowing like water! Blood tests will run about $75 to $125 total, and the radiography depends on your area - where I used to live, it would have been less than $200, but now that I'm closer to a major urban center, that stuff runs, well, you don't want to know. Fortunately I've never had a case where the vet actually called for an US, though they've always mentioned it as a possibility. And of course anything involving hefting dogs around is more for big dogs, so I hope they don't want to do this to Raja! [
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Okay, if the vet thinks there is immediate danger from the worm load she's carrying, they will give you an estimate of what the actual treatment will cost. My vet starts the dog on a course of blood thinner (aspirin if there is no danger to the GI) - about two weeks ahead of time, and that's when I start a dog on milk thistle, antioxidants, and other supportive supplements also.
There's usually two doses of the arsenic compound given about twelve to eighteen hours apart, so there will be an overnight stay involved. Painkillers and an IV will be used - my vet only tacks on charges for these things if she's feeling fiesty - as when someone pulls up in their Mercedes, who couldn't be bothered to keep up with the HW pills. [sm=devil.gif] I know other places do charge for that kind of stuff and it does add up.
Your dog will be a bit under the weather and sore the first day back home, then will feel terrific the next week or so. It is imperative, however, that she stay absolutely quiet - crated is best. The more quiet the dog is the first week, the easier the third week will be. Quiet is important because solid waste from the dying worms will be floating around in the dog's bloodstream and it takes up to four weeks for her immune system to process it all. Clots can end up in the heart, lungs, or brain if the heart voids these wastes too fast, while contracting during exercise.
But you can't see this happening and up to about halfway through the second week you'll wonder what all the fuss is about - your dog never seemed sick and now seems better than ever! Your vet will probably have you come in for a checkup to listen to the lungs and heart around this time and he or she will ask whether you've heard any coughing or retching.
Then late in the second week, the toxins from the dead worms will hit the dog's system and she'll look and act like death warmed over for anywhere from two to seven days. It's pretty awful. Sometimes if the infection wasn't too bad you barely get this - but I've noticed it every time. This is the worst part, though, and if you've done your homework it will go fast and with no real harm to your dog. My vet gives Rimadyl for this part but I rarely use it - I feel the pain keeps the dog quieter and I prefer not to challenge the liver further than need be. Your main job is to make her as comfortable as possible, encourage her appetite, and fix things that are exceptionally good for her like Satin Balls and crockpot meals! Plus you'll be listening for any coughing or barfing on your vet's instructions.
Sometime the last week she'll "bloom" but you are not out of the woods yet. It's still leash walking and crate rest until the doctor gives you the all clear. My vet will usually just recommend ivomec if the test is still positive after the fourth week.
My vet charges the least of any place I've seen in this state - it's $300 for the whole ball of wax - though as a rescuer and trainer I get about a 30% discount on that (they have named the new wing of their clinic after me, too). I think most other places charge from $400 to $500. If you feel comfortable shopping around, what you want to do is get a second opinion - I really think that if she has a really light load of just a few newly mature adults, that you would be safe with religiously treating with Hartguard.
I just realized that I know way too much about heartworms and their treatment. Does anyone know what mosquitoes are good for exactly? Because I'm suddenly wishing we could bomb them all. A friend who is a researcher in parasitology and a dog lover (of course), was wondering idly one day why we haven't seen any evidence of resistance to heartworm meds (resistance means the worms are unaffected by the meds). I said "A pox be upon you for even
thinking that!"