Hi Deanna, sorry you're going through this with Otis. I don't have any experience with ear infections, but just want to say I'm sorry, and hope he feels better soon. It sounds like you've tried everything, and trying to get the ear infections under control. The only things I can think of that can cause ear infections are yeast, food allergies, or getting water in the ears when having a bath. When I bath my guys, I soap up their bodies and rinse them with a hand held shower head, but I use soap,on a face cloth to wash their faces, and ears, and don't let the water run into their ears. Then I make sure I dry their head and ears really well after. I use unscented baby wipes in between their baths to clean their ears, faces, and nose ropes.