Lufenuron was marketed as Program years ago. It does not kill adult fleas!!!! It is now being sold under other names. Read labels closely. There are other insect growth regulators products : NyGuard and Precor. There are flea products sold in pet stores that are really cheap and sold in topical dispensers that look just like effective flea products that do kill fleas. Watch for labeling that says that the product kills eggs and larvae with out mentioning adult fleas.
Dr. Freesh saw a kitten that was full of fleas and the owner was faithfully applying an over the counter cheap flea product and the results were more and more fleas on the kitten and in the environment. The product was an insect growth regulator and was not doing the kitten or the owner any good. The owner was frantic. The situation was explained and an effective flea control program was instituted.