hi tos. my drs found out that the rsd was causing my stomach pain by ruling out all the other reasons i could have stomach pain. they did ultrasounds, catscans and mris and also took bloodwork. after they could find nothing else wrong they determined that it was rsd and my pm dr increased my pain meds to help manage my rsd spread to my stomach and increased pain from surgery. heating pads also help alleviate the pain a little. i also wear loose fitting clothing so that nothing is pressing on my stomach and i don't sit for long periods of time including in the car because it makes my stomach pain worse too. maybe your drs can run some of these tests too if they think its okay to do to find out if you do have rsd spread to your stomach or something else. i hope whatever it is that you feel better soon. soft hugs.