This was way back in late 2009. He would go on to live to be about 15. He was around 4 years old so he had to be neutered before the shelter would let him leave. My regular vet agreed to treat him for the cost of the drugs which was about $500 back then. First he had to be treated with steroids. I think it was prednisone or something like that. Basically his body was going to have to absorb the adult worms once they were killed off. After about a month of steroids my vet gave him regular heart worm medication to sterilize the adults and kill all the larvae. My vet let me look at his blood in the microscope to see all the larvae wriggling around between the blood cells. It was creepy. A few weeks later he got his first shot to kill off the adult worms. It was a long needle that had to go deep into his hips. When we brought him home he had to stay in his crate for at least a day. It might have been longer. A month later he got his second and final shot. It was the same deal. Come back and stay in the crate. The shot is a pretty strong poison so Samson just wanted to sleep it off anyway. He was a mellow dog and took the treatment well. After that, we gave him heart worm meds about once a month for the rest of his life. I think the medicine used is the same stuff that all the wingnuts were taking for Covid, Ivermectin. When your dog gets the big shots, keep them in the crate and keep everything calm and quiet. They'll sleep it off and gradually come back to normal. Your dog will probably put on some weight. Poor Samson blew up because he got neutered as an adult and then took all of the steroids. Your mileage may vary though. Good luck! 
Samson, right after digging a hole. 
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