I was taking Nexium but switched to Protonix because it's so much cheaper. But the last few days I've had a few painful bouts of reflux. What is the difference between reflux and gerd? I get a horrible burning sensation in my whole chest and back and my heart pounds. My throat feels like its tightening up. When I get these horrible pains, what can I take right away to aleviate it? I really don't know anything about this and I guess I need to read up on it. Anything you can tell me will be helpful. Thank you.