Hello, thanks for your question today! I am Dr. Drew, and I am a licensed veterinarian. I'll be happy to help you in any way I can.
All of the available products are great at preventing heartworm disease --
the differences are mostly in the flea control area.
My preference is Trifexis, which is a once a month pill that kills fleas, intestinal worms, and prevents heartworm.
However, there's little to no tick repellent effect.
If ticks are an issue, then a topical product may be needed instead.
or a tick collar can be used, such as Scalibor or Preventic.
there's not going to be a single product that does "everything" well,
so you need to decide what the priority is.
we currently have her on Trifexis, Thank you!
you are very welcome!!