Program Flavor Tabs are a once-a-month tablet for the prevention and control of flea populations in dogs, cats, puppies and kittens four weeks of age and older. Program Flavor Tabs do not kill adult fleas, but effectively and safely control flea populations by breaking the flea's life cycle at the egg stage. After biting a Program treated pet, the female flea ingests lufenuron which is deposited in her eggs. Lufenuron prevents these flea eggs from developing into mature adults.