I have GERD, but I was prescribe a medication for fibromylagia, I started having discomfort in my chest, like tightness, I stop taking the medication duloxetine dr 20mg capsules and lyrica. But I m still having the discomfort and it seems to feel worst when I raise my hands. When I rub my chest, I have systems of gas that I typically get from the GERD. Not sure if it may be a side effect of the medicine or not.