FRONTLINE® Plus (fipronil (S)-methoprene) for dogs fipronil /(S)-methoprene FRONTLINE Plus provides your dog with the most complete spot-on flea and tick protection available through your veterinarian. In addition to killing 98-100% of adult fleas on your dog within 24 hours, FRONTLINE Plus contains a special ingredient that kills flea eggs and larvae, too, and keeps ALL stages of fleas from developing. By effectively stopping the development of new fleas, FRONTLINE Plus completely breaks the flea life cycle. And, FRONTLINE Plus kills all stages of 4 major ticks including those that may transmit Lyme disease and Rocky Mountain spotted fever. You can use FRONTLINE Plus with ease and confidence. It's applied just once a month to a single spot on your dog, between the shoulder blades. It's completely waterproof, so your dog can swim, get wet, and even be bathed without the need for re-application. What's more, FRONTLINE Plus is approved for use puppies 8 weeks and older and over 11 lbs. FRONTLINE Plus - The best protection against all stages of fleas and 4 major species of ticks sold through your veterinarian!