I use ivomer Classic, Ivormectin is the ingredient that will be found in various treatments for different animals... The stuff I use is applied the same way as spot on is applied and the difference can be seen in a week! Although a good few years ago a vet treated a terrier I had with a fortnightly injection and the difference was obvious after the 3rd day... b*****d wouldn't give me the name of the stuff but he mentioned it had Ivormectin!! It can be dangerous to dogs if overdosed but little goes a long way anyway