No one in our household has ever had to be on it personally but I will tell you what information I can from our prescription drug reference.
It can be taken short term or long term (for instances of immune system suppression or multiple sclerosis).
Common side effects are increased appetite, indigestion, nervousness, insomnia, greater susceptibility to infections, increased blood pressure, slowed healing of wounds, weight gain, easy bruising and fluid retention.
You are advised to avoid excess sodium while on the medication, and to avoid medications that contain sodium and potassium, antacids, diuretics, along with others.
Given the number of disease contraindications and other medications, I would make sure you go over your entire health and prescription history with your doctor before going on it.
If I can answer any more questions, post back here, but this really is something you need to go over with your doctor if you have not already.
Good luck!
Lindaru