This summer we are gradually switching our inventory of Frontline Plus over to a product called Frontline Tritak. This new product is effective against adult fleas, flea eggs, flea larvae, ticks and chewing lice. As compared to Frontline Plus, Frontline Tritak has an added ingredient that aides in killing the fleas and ticks in a much shorter time (starts killing in as little as 1 hour). It is a monthly spot-on treatment for dogs or cats that is packaged in an easier-to-use ampule than the older product, Frontline Plus. Please feel free to contact us with further questions regarding the most appropriate parasite preventive for your pet. Visit the Frontline Tritak website for more information on this product.