Reviewed by: Cathy Carlson -LCS Customer Service Having dogs most of my life I just learned what it was like to battle the flea last year. We tried flea collars, shampoos, flea bombs and finally Frontline. My vet recommended that we start with the Frontline and continue throughout the year because of the life cycle of the flea. He showed us how to rotate the application in a circular area on the back of the neck getting it right down to the dogs skin. The dog showed relief within 24 hrs from the fleas and stopped scratching and chewing itself. We have continued with this product throughout the year and have ceased to have fleas. We have also noticed that we have not pulled a tick off of her for the past year either. Great product. I always keep a 3-month supply on hand.