Iknow everyone gets slightly different results with cortisone shots, but is it normal for sciatica relief right after, only to return 30 min later?

Yes / see below: Yes, the local with the steroids probably wore off. The steroids take longer to work.

No.: I performed two sciatic nerve blocks today. Steroids plus 2% xylocaine (lidocaine). Immediate sciatic paralysis will (did) occur and suggest that the injection was on target. If pain goes away, great, bit it does not return in one hour. May be simply systemic steroid uptake, which then would fall. I do not know what type injection you specifically had and was it guided.You may have had a steroid shot only!

Cortisone : The effect of local numbing medicine, typically found in the injection, can last for only a few hours. 30 minutes is really short. Sometimes it takes a week before the steroid takes effect. Maybe have a little more patience, and assess the situation in a week from the injection. Hope it worked!

Inflammatory vs numb: The steroid may take a few days to kickin- so it is impossible to tell if you have had any relief from the anti- inflammatory relief of the steroid. There are multiple anesthetics that can be injected with it. The fact that you had even temporary relief demonstrates that the correct structure was injected. Call the doctor who performed the injection and let them know your results. This is helpful.

May Want to Repeat: Epidural injection. There is a synergistic effect with injections in which you may receive more relief when 2 or more injections are used together. If you are not improving even after the 2nd injection, I would consider other options like radio frequency ablation or even stem cell therapy has shown good results. Pain can return before cortisone starts providing relief in 3-4 days, don't worry.