Rural mystic
New member
I know that this issue has been discussed quite a bit but here I go again.
Since Ace started heartworm preventative treatment I have been using Trifexis with no serious side effects. Other than perhaps a little lethargy after the first usage all has gone well. I resisted changing to Sentinel because Ace seemed to be doing well on Trifexis and it is what our Vet recommended and I was reluctant to change also because of the fear that he might have a negative reaction to Sentinel so I felt caught between a rock and a hard place. Like many others here I have had my concerns and have spent quite a bit of time researching both medications and the active ingredients in both. They both use milbermycin oxime for heartworm prevention the difference in the medications as far as the type of chemical used is in the flea and tick medication. Trifexis uses spinosad and Sentinel uses lufenuron. Each time I visited the Vet and it was time for heartworm medication I raised my concerns and each time was given reassurance that Trifexis was safe and etc and also kills the adult fleas vs only the flea larvae as Sentinel does. But each time I gave the treatment it was with fear and trembling and reservation. In the last couple of weeks, it being the time for treatment, I had Ace weighed and he was at 65 pounds so now He was prescribed the largest dose of Trifexis. He was on the 40-60 pound dose now up to the 60+ to 120 pound dose. This really bothered me. If a dose with a range of 20 pounds and the dog at the high end of weight was sufficient then at the 60+weight range, Ace being 65 he would be taking a dose that would treat a dog up to 120 pounds, that is practically double the weight and so the medication would have to be sufficient for the higher weight dog which gave me quite a bit of concern for Ace that just barely fit into that category. I got the medication but wouldn't give it and decided I would split the dose if I couldn't get the lower dose or seek another alternative. I didn't talk with the Vet this time but the personnel there said they couldn't give the lower weight range dosage as it wouldn't be sufficient. After doing more research, basically the same results as before, but one thing I have noticed during all this time was that the anecdotal comments on all the sites I visited range from about 60 to 70 percent or higher with negative comments and warnings on the Trifexis, it may not be scientific but for me its not something to dismiss out of hand. So anyway I am changing to Sentinel. The dose for Ace with Sentinel is in the 50-100 pound range, still significant but better in my opinion as Ace would be at about the median to higher end of weight for the amount of medication he would be taking. I had to jump through hoops to get it.? The Vet did not carry it on hand at the clinic and I had to go online through their prescription website to order it and it will be mailed to my home.
Since Ace started heartworm preventative treatment I have been using Trifexis with no serious side effects. Other than perhaps a little lethargy after the first usage all has gone well. I resisted changing to Sentinel because Ace seemed to be doing well on Trifexis and it is what our Vet recommended and I was reluctant to change also because of the fear that he might have a negative reaction to Sentinel so I felt caught between a rock and a hard place. Like many others here I have had my concerns and have spent quite a bit of time researching both medications and the active ingredients in both. They both use milbermycin oxime for heartworm prevention the difference in the medications as far as the type of chemical used is in the flea and tick medication. Trifexis uses spinosad and Sentinel uses lufenuron. Each time I visited the Vet and it was time for heartworm medication I raised my concerns and each time was given reassurance that Trifexis was safe and etc and also kills the adult fleas vs only the flea larvae as Sentinel does. But each time I gave the treatment it was with fear and trembling and reservation. In the last couple of weeks, it being the time for treatment, I had Ace weighed and he was at 65 pounds so now He was prescribed the largest dose of Trifexis. He was on the 40-60 pound dose now up to the 60+ to 120 pound dose. This really bothered me. If a dose with a range of 20 pounds and the dog at the high end of weight was sufficient then at the 60+weight range, Ace being 65 he would be taking a dose that would treat a dog up to 120 pounds, that is practically double the weight and so the medication would have to be sufficient for the higher weight dog which gave me quite a bit of concern for Ace that just barely fit into that category. I got the medication but wouldn't give it and decided I would split the dose if I couldn't get the lower dose or seek another alternative. I didn't talk with the Vet this time but the personnel there said they couldn't give the lower weight range dosage as it wouldn't be sufficient. After doing more research, basically the same results as before, but one thing I have noticed during all this time was that the anecdotal comments on all the sites I visited range from about 60 to 70 percent or higher with negative comments and warnings on the Trifexis, it may not be scientific but for me its not something to dismiss out of hand. So anyway I am changing to Sentinel. The dose for Ace with Sentinel is in the 50-100 pound range, still significant but better in my opinion as Ace would be at about the median to higher end of weight for the amount of medication he would be taking. I had to jump through hoops to get it.? The Vet did not carry it on hand at the clinic and I had to go online through their prescription website to order it and it will be mailed to my home.
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