Cortisone is not a pain relieving medication. Instead, it's a powerful anti-inflammatory drug which is synthetically manufactured to mimic some of the natural hormones in the body.

Given by injection, infusion or orally, the effects of Cortisone are usually evident within a few days, and the effects can last up to several weeks.

I don't have RSD but I do take Cortisone for MS flare ups. I know that I always feel heaps better after a few days of treatment, and I hope your daughter does too.

If you want more information about Cortisone, why don't you post over in the Medication Forum. I'm sure mrsD would be more than happy to answer any questions for you. Here's the link just incase : http://neurotalk.psychcentral.com/forum72.html