I have used Ivermec to kill ear mites. My cat had them and they were gone in one treatment. It is bad to use for a long time but a couple of treatments isn't bad. It is meant for cattle to treat mites but I worked at a pet store and we use to use it all the time and it did work for my cats. I do not remeber how much to give but you can get it from revival. Heartguard has a little ivermec in it. When you use it though it does kinda burn under the skin for a couple of seconds. But it works.