@Woolie - Do you get the impression (or is it too early to tell) that it can induce a remission, which might then last for a time, or that you will need continuous treatment? Do the positive effects wear off very rapidly?
This is a tricky one. I've always had a relapsing/remitting pattern to my MECFS, so its often hard to tell what's what. I suspect prednisone's more about relief of symptoms while you're on it. But I do have a hope that just giving my immune system a break from its usually massive hyperresponsive state might also be helpful in the longer term. It seems to me lots of the things that are found in our blood - for example, low or ineffective NK cells - might be caused by immune exhaustion. So there's my hope.
Pred is first line treatment for a lot of AI diseases, including lupus, crohn's ulcerative colitis, polymyalgia rheumatica, and also MS (in MS, massive doses are often given at the beginning of a flare).
On the mental side, I had trouble sleeping for the first few nights (maybe first two), but that's gone now. Sometimes, I feel like I want to get things done too quickly. When in a conversation sometimes my words kind of get in the way of each other, and I have to correct myself. Its like a kind of very mild buzzed state. Really mild though. I'm a university lecturer and can still give my lectures, and am still writing good articles, etc, so no real loss of quality there. Oh, and I also feel hot, even when its not.
Depression has been associated with increased cortisol levels. And there are warnings on the label that some people feel depressed in prednisone. These two things might be connected. But for me, I feel more cheerful than before the pred.
The positive effects don't wear off. The only other thing I'd want people to know is that its all about dose. When I first tried pred, I did 20mg. That worked for two days and then the symptoms came back. I raised the dose to 40mg, and the symptoms went away and stayed away. Soon I was able to gently drop the dose down 2.5 mg at a time, now on 25mg and still working. Blast-then-reduce seems to be a common strategy with prednisone. Most people who have commented here on PR have probably not taken enough pred to get enough of a reduction in immune activity to get relief.
@Eeyore, not sure you can tease apart a genuine response to infection from AI disease just from the way a person reacts to pred. Pred will reduce your immune response irrespective of whether its an ineffective one or a really useful one (e.g., the flu). So for example, pred is sometimes give to people with acute mono/glandular who are having a partiuclar bad time with symptoms.