In the early stages this drug can kill the adult worms in the heart and lungs. The bad side to the drug is that it can be highly toxic, causing damage to the liver and kidneys. Before this treatment can occur a veterinarian will request a full work up on the dog, including the blood test and x-ray, to ensure that this is the problem. After the treatment has begun the dog will receive more injections of antibiotics and vitamins. If all goes well the dog will be sent home to recover at home for the next four to six weeks.
Special medication is administered to eliminate any circulating heartworm larvae.
After treatment a veterinarian might request another series of tests to ensure that the heartworm is entirely gone. It is expensive and most owners do not want to fork the expense for this optional medication. It should be given daily or monthly depending on the particular medication, but most definitely should be given during mosquito season. The veterinarian will have a recommendation on how often the heartworm medication should be given depending on the drug itself and the region you live in. Ivermectin is a popular heartworm preventative that is usually administered once a month.