Yesterday I went to my primary doc following an MRI of my upper arm/shoulder. He wants me to get off prednisone. He said "have you ever seen anybody with Cushings?" I said no and he said to look it up on the internet. I've been on pred this time for 6 mo. and am at 6.25 mg. Can't seem to lower it w/o awful pain in my arms, wrists, hands and knees. So I asked him what I could take instead. he did not have any answer for that.
I don't know if your doctor has much experience with PMR or with prednisone. Cushings is basically a condition that results from too much cortisol being produced by the body, which is similar to continuous high doses of corticosteroids (i.e. prednisone). However, 6.25 mg is a moderate dose of prednisone. Do you have a rheumatologist you can talk to? Are you experiencing bad side effects from the prednisone? How long do you wait after lowering your dosage to see if the pains go away? Are you lowering by just .5 mg at a time?
Here is a link