If you are burping every 3 minutes you might want to take something with simethicone in it to relieve the gas/pressure which might help with the GERD.

There is a ring of muscles around the base of the esophagus and the top of the stomach. Reglan will help increase muscle tone there and help keep things from coming back up. If you are having to take 2 Protonix and Zantac, it might be something your doctor should prescribe you since yoiu are still having trouble.