Steroids, like any medication, can be quite harmful on the body... of course, we also know how great they can be to help get us into remission fast.
Also, like other medications, the more you take them, the less effective they may be the next time.
They are very helpful, and I know they were just phenomenal to help me both times I needed them. Each person's different, and each symptom's different. Some people are okay to 'ride it out', others need the extra help of the steroids.
When I was lying in bed and could not feel my right leg at all (purely sensory - it 'worked', but it was if the leg had been chopped off - scary), I knew I was in deep doggie doo, and I needed help (IV Solumedrol, steroids) pronto.
I didn't rush for them when I developed crushing pain in my noggin though... I went to a pain doctor and got a prescription that helps.
I do know the pros/cons discussion over steroids is much more 'involved' than what I know of method of action of the medication, so I'm certain another will chime in with explanation.
I hope you feel better soon and I hope that the steroids help you.