I have had three of these blocks with very short term results. Mine were placed high in the neck, and I did have what was called a rare complication. It was a spinal fluid headache and it was the mother of all headaches. My doctor had me go to the ER for a head scan and blood pressure monitoring, and I finally had my son help drag me out against MA because they treated me so badly and I couldn't take the noise. The headache lasted about a week and I was in bed with it for three days. I wish you luck with your blocks, and I do need to mention that I had treatment resistant RSD for a long time. Good luck, Lisa