Very normal for cats -- AND dogs, especially dogs with drop ears, like mine. It happens, now and again.

Ear infections can be either yeast or bacteria. These 2 are are different ends of the pH scale, so the medication for one will not help with the other. This is why the vet had to look under the scope, to determine exactly which type of infection it was ( and to verify no mites, of course).

Poor kitty sure has been miserable, I am so glad you were able to get the cat in to the vet, and get the meds. Bet that kitty will love you furever, he hee. Joking, this is a CAT after all. Anyway, a few days on the meds and the cat will feel LOTS better!

One of my dogs, Lacey, is quite prone to ear infections (either type, she doesn't discriminate) so I take preventive action. I use Oti Clens to clean her ears, twice a week. My other dogs, even though the same breed, are not in need of this. So depending on the cat's age, how long your friend has had her, this may or may not be something to consider in the future.