Have had IBS symptoms for 6 months, which mostly can be handled with diet. Sometimes if I eat something I shouldn't, I get an intense headache and my pulse starts racing, blood pressure goes up, and I get pains in my chest, before an onset of diarrhea.

These symptoms are scaring me to death and I wonder if anyone else gets this intense a reaction?? Please advise.

The heart racing, yes, that I am VERY familiar with. When I'm having a bad IBS attack, my heart speeds. All I can try to do is take very small, slow, shallow breaths and put cold water on my neck and wrists. I think there's some connection between the stomach, the trauma from the bowel spasm, and release of adrenaline. I think that's the biggest reason why I'm so exhasuted after it's all over.

It's possible the pain you're having is because your heart is beating so fast. But I couldn't say. I suggest seeing your doctor about it ASAP. Most likely, they will set you up with a heart monitor so the next time you have a spell they can log what's going on.

Oh, and it's also possible that you have a true allergy to something you're eating, not just an intolerance that makes digestion get messed up. You might want to test for that as well.