I am having a dog get treated for heart worms in about a month.

Heartworm disease is a horrible devastating disease. Fortunately, there are medical treatments for it that your veterinarian can perform and supervise. As with all medication, there are adverse effects, but serious issues are very rare. I would recommend speaking to your veterinarian and asking her to give you their client education piece on the treatment they intend to use.

Later on (timing depends on your vet's recommendations), you can put your pet on a heartworm preventative to prevent this from ever happening again.

This is a great site for all info about heartworm disease: www.heartwormsociety.org