How many symptoms of Heart worm do dogs get before it is too late to help them?

My 8 year old dog has almost all the symptoms of heart worm (weight loss, occasional cough, doesn't run around like she used to). My mom thinks it is too late to help her. I don't want to put her to sleep if I don't have to. What is the chance of her living if we give her the treatment? Is there such a thing as "too late to help" her?

This is something you need to ask the vet. Since it's now quite apparent that heart worms do strike in your area the next time you get a dog get it on a preventative.It's always been my understanding that once obvious symptoms have appeared it's probably too late for any kind of guarantee of treatment. Talk to the vet. It may not even be heartworm, but it is NOT fair to let the dog suffer while the family plays the "guess the mystery disease" game.

it may or may not be heart worms but it's never to late to get a heart worm test and if it's negative to start prevention. when you take her to the vet they'll listen to her heart and lungs, do a heart worm test, and maybe even an x-ray. treatment for heart worms is very hard on a dog and the damage done by the worms will always be there. so take her to the vet and see what's going on before you give up on your dog.good luck