I think heartworm meds are a scam. Just a way for the vet to shake you down. They make big bucks off this stuff. I've never seen a young dog die of heart worms. I've seen old dogs with heart worms that were going to die anyway. Maybe their lives were a year or two shorter because of the worms. Heart worm meds don't guarantee longevity.
Big shakedown, huh?
I prefer not to gamble with my dog's life.
I hope you don't have any dogs. I'll bet you're one of those who never gets his dog's teeth cleaned either. Another scam?
Some people should not own dogs, or cats, or have babies.
I thought the same thing until three years ago when both of our dogs were diagnosed with heartworms.
We paid megabucks for the heartworm treatment, and now give them heartworm pills every month.