Heartworm disease is deadly. The worms sit in the valve between the right side of the heart and the lungs, interfere with blood flow, make the heart bigger so it works less efficiently and can have some unusual side effects, and can lead to death. However, there are different ways to go about treating it. The standard is treatment with Immiticide (Merial), a much safer treatment than the old arsenic derivative of 20 years ago. But, again, there can be complications, like death – these can occur with no treatment as well. Full treatment protocol includes chest radiographs, bloodwork, a few days of hospitalization, and some anti-inflammatory medications, oh, and the Immiticide– this adds up, especially for the big dogs. But it kills the worms right off. Some people can’t afford the full treatment. Then what? For safety of your pet, it is never recommended to wait 2 years for the adults to die, but that is what some pet owners do. CONTROVERSIAL: These pet owners put their dog on heartworm preventative, which keeps new infections from building, and keeps other dogs safe from a mosquito that would have bitten your heartworm positive dog. In that 2 year waiting period, the adult worms are damaging the dog’s heart and making babies that can be “eaten” by a mosquito and transmitted to another dog. There are some alternative medicine choices, none are “proven” in a laboratory, but I have 3 clients who intentionally sought out a different way. In the long run? Their dog is in the same place as a dog who underwent conventional treatment.