Recently I gave my kitten a dosage of the Hartz flea medicine that is “safe for cats and kittens.” Three hours after administration of the medicine, the kitten began to violently shake and tremble. These episodes were periodical in that they would last about a minute, then die down for a minute. It is important to note that these symptoms started suddenly and violently. The emergency room veterinarian has reported getting several cases a month of poisoned cats because of the medications toxic effects and he was honest in stating that he believes the Hartz flea product is one of the most dangerous medications for animals. Frankly, there is no excuse for having such a dangerous product readily available on the shelves. The company has proven themselves irresponsible and lacking basic business and moral ethics. Not only does this product kill the fleas, it kills the cat too.