What should I do if I miss a dose of my cat’s heartworm prevention? - The Drake Center
You should just go ahead and give the next dose. Alert your veterinarian that you missed a dose. If you live in an area with high incidence of heartworm disease, they might recommend a test. But you should just keep giving the dose. In fact, even if a cat has heartworm disease, we still keep them on the preventative because we're preventing more worms from developing. It's not wrong to give the next dose, but talk to your vet about it.
Can I do anything in my cat’s environment to reduce the risk of heartworm? - The Drake Center
Are there any holistic or over the counter cat heartworm prevention? - The Drake Center
No, nothing works. If you could put your cat in a bubble so they would never get bit by a mosquito, that would be great, but obviously, that's not plausible.
Can prevention be used to clear a heartworm infection? - The Drake Center
No, it differs. Prevention entails preventing the disease. It's not going to treat the cat if they already have heartworms. Like I said before, there is no treatment for heartworm in cats. There are treatments for the side effects that they cause, but there's no treatment to kill the actual worm.