Heartworm is not a vaccine as we think of when we talk about distemper or such. Heartworm meds kill any and all larvae that have grown in the blood stream in the PAST 30 days. It does not work forward and that is why it is so important to give it on schedule. I use Ivermectin 70mcg for each dog. I know most use Heartgard (PLUS) and other tabs, but I use the straight Ivermectin and have had not one problem in over 10 years.. |