Parasites are not only a pest they can make life hell for a cat or a dog. This is because they cause severe itching or even trigger an allergy, such as from flea bites. Frontline Plus doesn't just kill adult fleas and ticks but also slays the next generation of flea eggs and larvae. Plus, it works non-stop for 30 days on dogs. Get your pet on flea control or a worm prevention product as soon as possible.