Glad that I found this topic here about Prednisone and mood swings and Bipolar Disorder. My dad had to be on Prednisone whenever his asthma flarred into bad wheezing/cough as at that time that was all that would help him breathe. He had to be on it for awhile and the first few times it made him silly and a bit wierd, but he was able to be home. Then it seemed the dose increased or somehow it built up and he actually turned psychotic not just the Bipolar, he had SEVERE issues and he had to be psych hospitalized whenever he was on it just about. We could not have him on that and be home, as he began threatening, yelling, very verbally abusive and frightening. He had increased strength and he was very much a danger. Be very careful using Prednisone, if you have a mood disorder.
Prednisone is a strong and powerful steroid. I have read that it can help those with muscle weakness to be stronger. It may be good for some people for asthma and other things such as shingles and kidney problems (which some people I know have used them without any big issues). However, I won't ever take Prednisone at all and I have had chronic asthma and wheeze and have refused Prednisone whenever any doctor mentioned it.
There are now many other asthma medications, I'm on Pulmicort, Singular, Albuterol, and Combivent and they do help with the peak flow at least. Those I take daily. I recommend anyone to go to a qualified lung doctor. Duo Neb was also very helpful for awhile. All of that though is of course expensive. The Albuterol and Combivent are Steroids, however, not like Prednisone. I don't like to take prescription meds though, but for now I haven't found a natural therapy that will help my breathing.