VetGuard Plus For Dogs is an effective and easy to use product. This product has demonstrated greater than 92% control of fleas within one day of application. This product prevents eggs from fleas on treated dogs from developing into biting adults for up to 4 months. As with all flea and tick control products, this product should be used as part of a program aimed at reducing flea populations in the dog"s environment (bedding, carpets, kennel, yard). Consult your veterinarian, entomologist, or retailer for program recommendations.