Sciatica and pain Dam Back .. Help

I was on Robaxin 750mg, upto 12 times a day. I feel good while Im taking it but the day I stop, is the day the pain comes back.
I did get a steroid pill pack today(6 pills the first day, 5 pills the second day, ect) Methylprednisolone... I will see how this goes.
I will also take the posture and other recommendations posted here into account.