my bunnies health and symptoms

Question
About a month ago my healthy five year old lop started losing his fur along his back to start and now his entire underside and down his legs is all pink, along his back is dry scaly skin in places in others very pink. We have been to the vet four times, three shots of ivermectin (the mite shot) we started off with tribiffin and now he is taking baytrill.  Our next step is an anti fungal but that I understand can do liver damage. He is eating up a storm and drinking lots of water, has lots of spring mix, baby carrots, carrot greens, 1/4 cup commercial pellets twice a day (they have treats in them) plus fruit twice a day for the past three weeks for all the meds as he wont take them otherwise.  The fur falling out has lessened considerably but that may be that he has lost so much already.  He has his own room in the house, a cage in the back hall and one in our air conditioned room that he can go in and out of when he is hot or that we will put him in if its humid and too hot out. he always used to run to his cage to urinate or leave droppings in fact he would run from whatever room he was in now he is leaving piles where ever he happens to be and urinating on the floors so out of character yet seems to be moving around well. He runs to the fridge whenever he hears it open. Not sure where to go from here. I thought perhaps he was diabetic but everything I read says it is very rare.  Any suggestions would be appreciated. Thank you. He is part of our family and we just want him well

Answer
Dear Susan,

If you can send pictures to hunhare@gmail.com or attach them to a post to AllExperts, it will help.  Clear, close-ups are best.

If the ivermectin has not worked, I would recommend a skin biopsy.  This  could be a very nasty condition, sebaceous adenitis.  It is an autoimmune disease, and it can be progressive. There are some treatments that have helped in some cases, and if this is the problem then the sooner these are started, the better.

I hope I can help with this.

Dana