Yes, I still use the Ivermectin monthly. However, I no longer use the .1 cc per 10 lbs as that is waaay.. to much for simple heartworm prevention. I may use the .1 cc per 10 lbs couple times a year to prevent other parasites, but now I have gone to .1cc for each dog per month and that is still more than you would get using Heartguard.