Hi there my dear.... Not sure neither if all RSD or all meds. I have always got a burning in tummy also... Throwing up is nothing new to me neither.. Loosing weight,,,, lots I have lost.   Here again,, I use naturals from health food store.. Only thing that helps keep food down,,,, n helps with the burning.  Know that you should not be taking medicines with out food.  Always have something in tummy..     I do not know it totally rsd.. I think that alot of us have the upset tummy my dear.  Hoping that you get thru all of this. Not good to be taking off weight too fast. Make sure that you are eating yogart also,,, helps also with the burning.  Dr wants me eating  four too eight cups of that a day..   Reason being my age.   Something else that can help,,,  getting  pudding that you cook,,,,, not the instant,,, when I get up in morning with being really  sick n heaving on empty tummy,,,,,   eating the warm pudding  really really soothes it all down...   Hope that something works.. Huggzz tite                                                      Annie