Specially developed to make worming easy, without the bites, scratches and other problems associated with trying to give tablets to a cat! Simply apply the solution to the back of your cat's neck for fast effective tapeworm treatment. Spot on dewormer starts to work almost immediately and is 100% effective at controlling tapeworms in cats and kittens. There is no permanent treatment for worms. Vets recommend that weaned kittens and adult cats shouldbe wormed every 3 months as a routine measure.