Profender cat wormer 2.5-5kg 5.5-11lbs No Rx Prescription Required. Profender is the world first so easy to apply spot-on intestinal wormer for cats. This product is for external use on Cats and kittens 8 weeks or older. It contains two active ingredients - emodepside and praziquantel - which are quickly absorbed through the skin to give effective control of all gastrointestinal worms.