What Causes Abdominal Pain Along With Diarrhea And Vomiting In A Toddler?

2 yrs ago I began having intense stomach gas pains, diarrhea, and vomiting. It is episodical and lasts several hrs at a time. I am an RN and aware of my habits and triggers. It happens Q3wks or so and at times I can go several months without it. I was diagnosed with PTSD and do have a trauma history. I do take meds for this. This doesn t make sense to me. I can not connect this to my mental situations at all. After a month without it it is back. I ate cheese Danish for breakfast and lunch, Steak and tomatoes for dinner. My stomach is often bloated and distended. My gyn apt showed nothing. I wonder Hpylori, cancer? I have seen my PCP and of course my psych dr. Meds adjusted in Dec. and Jan. and all has been quiet except for 3 sporadic episodes. Besides a colonoscopy and egd anything I m missing?