I have used Heartgard Plus on numerous dogs over the last 15+ years. I have seen it prescribed for thousands of dogs in the vet clinics where I have worked over the years. Never have I seen a case where a dog developed a heartworm infection that was not related to owner error (e.g., forgetting to give the dose or under-dosing the dog). That's not to say it's right to withhold evidence about the product's efficacy (if that did happen). But, to be honest, I cannot say that this case will change my opinion of the product.
Whether you choose to give your dog Heartgard or one of the many other heartworm prevention products, just make sure you are giving something. In most of the US, mosquitoes have been out in full force, nibbling away at us and our dogs. Mosquitos also happen to transmit heartworms, a serious parasite that affects the heart and lungs of dogs (and sometimes cats as well). This life-threatening disease can easily be prevented by using heartworm prevention AND having your pet checked yearly for heartworms (a simple blood test).
Do you use Heartgard? Does this pending lawsuit change your opinion of the product? If so, will you be changing to a different product? Tell us why or why not by leaving your comments below.