I do not recommend ivermectin injectable for cats. There are much safer meds, that do the same thing. Milbemite topically in the ears for ear mites, oral ivermectin in heartgard for heart worm and intestinal parasites, and Revolution topically for flea control are all examples of safer medications for cats. The strength of injectable ivermectin is designed for swine and cattle; any dosing of cats needs to be done by a veterinarian on a case by case basis.