We use Roadrunner Pharmacy, so the prescriptions are their brand. The heartworm preventative is a gelcap called MyPOL which contains Milbemycin, Praziquantel, Oxantel, and Lufenuron. It is given once per month. The flea/tick preventative is a topical spray that you apply to the dog’s back once per month. It is called Fipronil.