I took a quick cursory glance around the forum and didn't see anything about health related questions. I'm rather new here, so forgive me if this is posted to the wrong sub-forum. Before I begin, I'll provide a little background info up to current time. First off, I know that if I'm very concerned I should take my pet to the Vet. That being said, to take a blood sample, and to do an external skin biopsy on my ferret, it would cost an upwards of 400 Canadian dollars. And that is just the tests. Altogether I'm looking at $600, and the vet may or may not have an answer for me. So I've come here for a second opinion before I drop this much money on something I can't easily afford. up until the beginning of July this year my 2.5 year old, was healthy. In July I brought concerns of waxy ears to my Vet during a check up. The vet said that it may be ear mites. Upon taking a sample of wax from her ear, then checking it, the Vet said she could NOT find any ear mites, or eggs. However, the signs were all still there. As a precautionary measure, she prescribed an Ear Mite external medicine that I apply into her ears (meant normally for cats, its labeled) called Oridermyl. For two weeks I applied this, and the issue seemingly cleared up, or perhaps it was because I was cleaning her ears on a daily basis. Around August 30th/31st I had noticed that she was missing fur around her ears. Her skin is pink and healthy, however there is the odd occasion, where she does scratch herself with her hind leg. It's not often enough to make me think she's itchy, and only really happens as she's waking up. She is not missing hair anywhere else, and as far as I know, she didn't get her head caught in anything and tore patches of fur out. She is a Marshal ferret, spayed, and de-scented. She has no contact with any other animals, but receives lots of attention and playtime, and is rarely alone for long periods. Her mood is very playful and she is not lethargic, or otherwise unhealthy. I've checked her body multiple times for other hair-loss, and even gave her a full bath with ferret shampoo. She is eating well, and is having normal bowel movements, and does not appear sick, or ill. The Vet suggest she gets a blood test, and an external skin biopsy, which as I said is a rather expensive "I might find out what's wrong" with no for sure answers. Has anyone else had any experience with hair loss around the ears, or have any knowledge or what it might be? I generally ruled out Adrenal Gland disease, and understand while the hair-loss caused by adrenal gland may happen anywhere, it generally starts around the base of the tail, or on the trunk of the ferret. I've ruled out ear mites as she was just medically treated for them. I've rather ruled out many ideas of what it possibly could be, but lack the experience to know for sure if I may be correct or not. She enjoys burrowing under and than into my 7 year old couch. While I keep a clean house as best I can, shes really made a nest for herself inside the bottom of my couch. I wondered if maybe she was rubbing her head on something inside, or got it caught once, or twice, or perhaps re-contracted ear mites from the innards of the couch because that was one of her main sleeping places. I understand the only way to know for sure is to go to the vet, pay the very expensive bill, get the tests done, and if I'm very concerned, to go to the vet. However as I said I wouldn't mind a second opinion. I also wouldn't mind any advice from someone who's had a very similar experience. I apologize for the long wall of text, in my line of work, (a network IT) people tend to give a lack of knowledge or miss out important details. I provided everything I can, thank you for reading.

Hi there. I had one ferret who had mites that also developed a yeast infection in his ears.  He was prescribed drops that cleared it up.  The reason I took him in was because he had scabs on his ears from scratching.  You could try an antifungal cream applied with a q-tip, but I would think the scratching would be almost constant.  Rocky's was.

Adrenal hair loss can start anywhere, but so can seasonal shedding.  

THE DOOKS OF HAZARD

It most likely is because the vet prescribed the WRONG dose. You said it is labelled for cats and not kittens. The cat miticide is a few times stronger than the kitten kind used for ferrets. It will kill mites but it will also kill the ears which sounds like this is what is happening. From this little fumble it sounds like the vet is not ferret knowledgeable. I'd start looking for a ferret friendly one if possible and tell him/her you think the dose was too strong. In extreme cases ears have needed to be removed.