Trifexis or Iverhart?

Which heartworm med do you prefer? Pros and cons of both?

All the families dogs, except Kieber, are on Iverhart Max. Kieber is on his free Trifexis dose.

We don't have a bad flea issue here, but does Trifexis actually help with fleas?

Trifexus has had too many issues/is too new for my liking.

I like Heartguard Plus. Isn't Iverhart the generic version of that?

Trifexis is Comfortis (spinosad) + Interceptor (milbemycin oxime). Comfortis is the flea med, the latter for heartworm. I used Trifexis for probably six or eight months while the Novartis plant was shut down and I couldn't get Interceptor. Now they don't make Interceptor by itself anymore, so I use Sentinel, which is Program (lufenuron) + Interceptor. Sentinel happens to be cheaper for me... that's pretty much the only reason I use it instead.

Iverhart, OTOH, is Ivermectin, plus meds for worms, no flea meds. And if you own one of the breeds that are sensitive to Ivermectin, you probably don't want to give it.

As to the ones that DO have flea meds - both Comfortis and Program have been around a long time. I've never actually had a flea "problem" - my boys did bring a few fleas back from the woods once and I spied a few dead flea bodies around the next day, but they were on Sentinel and Frontline both at the time, so... which killed the fleas? Not sure. Anecdotally I've heard the oral meds work better on fleas than topicals, but I can't say for sure from personal experience... I use the Frontline for ticks, not fleas.


I have shelties so no Ivermectin over here, but I don't have any strong feelings one way or another about either being "better" for heartworm than another. Personally, since I use a topical for ticks that also does treat for fleas, I would prefer to give an oral med that does NOT contain a flea med (although the meds are different.) But there's no option for that on the market right now for me. That might be the route you prefer to go though, through the Iverhart.

I had Leo on Trifexis last year but he developed a reaction. He had hair loss and itchy skin. We weren't sure if it was a food allergy or the medicine. We changed his protein and a year later I started back on trifexis. We are now in our third month and so far I don't have any complaints.

Honestly, looking back I would've liked to wait a couple years and just use topical for flea/ticks. Since my family owns a boarding and daycare facility and we live near woods I like to know he is on a preventative for internal parasites... Although coccidia and giardia are not covered. There are just so many unknowns. And I'm not talking the "Trifexis killed my dog" articles but more of unknown side effects. I think in another year or two when there is more research available would be a better time to start it.

I'm a hypocrite though... unless I see issues I will be continuing.

I have used Trifexis and didn't have an issue. But, I can't afford it to keep them on it. So I currently use Sentinel, and likely will continue to do so if I have to purchase prevention.

Trifexis works very well on fleas, IMO. It also treats and controls whipworms, which is good. (As does Sentinel.)

I never did care for Iverhart. It's palatability is lacking. The fact that it treats tapeworms is nice, though.

I use Iverhart Max and Frontline Plus (fleas & ticks)