Our 6 month old cat has had tape worms for the longest time. They were completely disgusting and a constant source of woe in our household, as they are very visible as small sesame seed looking objects. They're apparantly extremely common in all young cats and can be acquired simply by being in the presence of fleas or mosquitos which can transfer eggs. We tried other products from Wal Mart but it was completely ineffective and also much more of a pain to administer. This product was a thousand times better; it is a small pill so it can be easily fed mixed with cat treats. The package comes with 3 pills yet it only took one to kill the worms completely in under 2 days. Its been months now and the worms are still gone. The price of this product is very affordable, especially when compared with vet bills which can get into triple digits for deworming. There were no adverse reactions or differences in the cats behavior. I would definitely recommend this product.