Yes, I was put on Prednisone for the Fibromyalgia, but unfortunately gained 50# in two weeks and had to be taken off because I was allergic to it. I recently was diagnosed with Secondary Adrenal Insufficency, Hypocortisolism Hypodrenalism and Hashimotos Disease. I found an amazing endocrinologist and what they had suspected 30 years ago (the Secondary Adrenal Insufficiency) he found. He told me that it is common in people who have Chronic Fatigue Syndrome and Fibromyalgia and he was very surprised that I had functioned as well as I did for this long. I finally had the answer to why I could never rush to do anything - I didn't have the adrenalyn to keep up. He put me on hydrocortisone - a small dosage and it has helped. I was reluctant to go on it because of the problems that I had with Prednisone previously. Prednisone is the other thing that they use to treat this. There are very few doctors that specialize in the Adrenal glands and I was extremely lucky to find one. Now though because of being on the hydrocortisone, my immune system is compromised and I have to be very careful and if I get sick, I have to increase it and call him right away to make sure that I am taking enough. I also wear a medical alert to let them know of this so that if I am in an accident or get sick that they know to treat it right away. He also had me put on it that I was on pain meds so that they would also be given right away. This is very knew for me so I am learning a lot and finding out that many things are tied to Fibromyaligia or it is a cause or result of others. Like you, a lot of people think that I have something else, such as MS because of the fact that my arms and legs are so weak and I am losing more and more strength in my arms.
I hope this helps a little and if you have any questions, please feel free to contact me.
Lois