I think it's related to something you have eaten or might have contracted...although given that it's recurring, I imagine it's something you are eating. I actually just started having the same problems today (sulfur burps/gas and diarrhea), as did my boyfriend (same day) after being on a trip together. So that makes me doubt that it's rooted in a chronic illness, but maybe different things can cause it. I imagine that he and I both ate the same bad thing. I read in another forum that maybe high amounts of animal protein are a cause, because the gases are a byproduct of the digestive process. Not sure though, especially if a doc couldn't give a solid answer!
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Sulfur/rotten egg burps with gas � vomiting.