frontline plus flea and tick treatment for dogs (medium dog, 23-44 pounds, 8 doses) frontline frontline plus flea and tick treatment for dogs and cats is a fast-acting, long-lasting and waterproof flea and tick protection proven to kill fleas, flea eggs, lice and ticks. designed for dogs and cats eight weeks of age and older. stored in the oil glands of your pet's skin, one easy topical application works for 30 days.