Where Do the Dead Heartworms Go After Killing Them?

A dog with heartworm needs multiple injections to remove them.
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If your pet has been infected by heartworms, your vet will treat him to kill the worms. Typically an infected dog gets a drug known as Immiticide, which begins killing adult worms immediately. When heartworms die, they begin to dissolve in your dog’s bloodstream. If the infestation wasn’t too bad your dog’s body can usually cope, but if your pet had a lot of worms, the debris could clog his arteries and lungs.


Inn some cases your vet may not be able to safely treat your dog with medication for his heartworm infestation. This is usually because the worms have made your dog too ill to survive treatment, he has too many worms present or he has other health issues that preclude treatment. A dog that has severe infestations and shows signs of serious illness must have the heartworms removed surgically, if he is strong enough to withstand surgery. Physically removing the worms avoids the risk of having bits of dead worms drifting throughout your pet’s body, but it’s still major surgery, which carries risks of its own.