5. Address the envelope. In the lower right third of the envelope, write the name of the person you are sending the letter to. Write the company name on the line below that (if there is a company name).
Once inside a new host, it takes approximately 6 months for the larvae to mature into adult heartworms. Once mature, heartworms can live for 5 to 7 years in dogs and up to 2 or 3 years in cats. Because of the longevity of these worms, each mosquito season can lead to an increasing number of worms in an infected pet.
Step Two: Treating the Disease. Once your dog has completed the course of steroids, heartworm preventive and antibiotics, he should be ready to start the actual adult heartworm treatment. The treatment for heartworm disease takes at least 60 days to complete and consists of a series of drug injections that kills the worms. There is only one drug approved by the Food and Drug Administration to kill adult heartworms in dogs, an organic arsenical compound that is injected into the dog's lumbar, or back, muscles.