The effect of the daily or monthly heartworm preventative is to prevent the development of the heartworm larvae into adult worms. It does not kill the larvae. Theoretically, even if only one pill is missed, it is still possible to develop the disease.
We advise, although a dog is on the heartworm preventative year-round, he/she should be tested once a year. If you are certain your pet has received and ingested each monthly dose, we will allow every other year testing if you wish. If the preventative is given to a heartworm positive dog, the results can be disastrous to the dog, including death.
I understand if my dog has heartworms, general anesthesia can potentially be fatal.
I have read and understand all of this and still have chosen to forego the test. I understand administering the preventative is solely at my own risk and will not hold New Baltimore Animal Hospital responsible for ANY adverse effects.